HomeMy WebLinkAboutStaff Report 2404-2860CITY OF PALO ALTO
CITY COUNCIL
Special Meeting
Monday, June 03, 2024
Council Chambers & Hybrid
5:30 PM
Agenda Item
19.Informational Report on the City of Palo Alto Utilities 2024 Water Gas and Wastewater
Utility Standards
CityCouncil
StaffReport
From:CityManager
ReportType:INFORMATIONREPORTS
LeadDepartment:Utilities
MeetingDate:June3,2024
StaffReport:2404Ͳ2860
TITLE
InformationalReportontheCityofPaloAltoUtilities2024WaterGasandWastewaterUtility
Standards
BACKGROUND
TheCityofPaloAltoUtilities(CPAU)Department’sWater,Gas,andWastewater(WGW)
EngineeringDivisionimplementsstandarddesignandconstructionspecificationsforwater,gas,
andwastewaterfacilities. Citystaffandcontractorswillreferencethesestandardsfor
constructionworkonCPAUͲownedfacilitieswithinthepublicrightͲofͲwayandonprivate
propertytoensurethatutilityinfrastructureisconstructedandmaintainedinasafe,uniform,
andreliablemanner.TheWGWUtilityStandardsincludeinstallationrequirements,material
specifications,andstandardizedconfigurations.
ANALYSIS
CPAUEngineeringstaffupdatestheWGWUtilityStandards1periodicallyandlastissued
revisionsin2022.This2024editionreflectscurrentconstructionmaterialavailabilitytoexpand
procurementmarketplace,andincorporatesuptodatefieldpractices,contractmanagement,
aswellasothernonͲsubstantialtechnicalediting.Thesechangesresultinclarifyingcontractor’s
responsibilities,enhancingstaff’sabilitytoenforcecontractrequirements,andreducing
contractdisputesorpotentialchangeorders.Asummaryofthemoresignificantrevisionsto
the2024WGWUtilityStandardsisprovidedbelow:
x Rewordedsomephrasingandaddednewlanguagetoincreaseclarityofstandards
andrequirements(invarioussections).
x IncludedadditionallanguagetoclarifyContractor’sresponsibilitiesonconstruction
projectstohelpCitymanagecapitalimprovementprojectcontracts(invarious
sections).
x AddedasentencetoensurethattheContractor’scostsavingproposalmeetsthe
1
WGWUtilityStandardshttps://www.cityofpaloalto.org/files/assets/public/v/8/utilities/utilitiesͲ
engineering/generalͲspecifications/2024ͲwgwͲutilityͲstandard_onlineͲversion.pdf
intendedperformancegoals(Section800).
x OutlinedthetimelineforNoticeofAward,ContractExecution,NoticetoProceed,
preͲconstructionsubmittals,preͲconstructionmeeting,andtheanticipatedstartdate
ofconstruction(Section800).
x Addedrequirementsforphoto/videoofpreͲconstructionconditionsandprocedures
forreportingsanitaryseweroverflows(Section800).
x Includedadditionalrequirementsandclarificationrelatedtotrafficcontrolplansand
constructionhoursforUtilitiescapitalimprovementprojects(CIPs)(Section1500).
x DetailedthepreͲinstallationpotholingrequirementstoprotectexistingunderground
utilitiesandaddedalinkfortheCIPcontractorstopreviewthelocationsofPG&E’s
highpressuretransmissionpipelinewithinPaloAlto(Section2200).
x Changedtheclearancerequirementstofurtherprotectexistingundergroundutilities
(Section2300).
x Updatedsomewaterinstallationproceduresandpartstoreflectcurrentindustry
standards(Sections2660).
x Addedspecificationsfortemporaryrepairclampusedongaspipe(Section2685).
x Updatedthetestingproceduresfornewsewermanhole(Section2738).
x ClarifiedthepreͲconstructionandpostͲconstructionvideoinspectionrequirements
(Section2739).
ATTACHMENTS
AttachmentA:2024WGWUtilityStandards–CleanVersion
AttachmentB:2024WGWUtilityStandards–RedlineVersion
APPROVEDBY:
DeanBatchelor,DirectorofUtilities
Staff:SilviaSantos,WGWEngineeringManager
Water Gas & Wastewater
Utility Standards
2024
Utilities Department
1
INTRODUCTION SECTION 01
CITY OF PALO ALTO Section 01 PAGE 1
SECTION 01
INTRODUCTION
1.01 INTRODUCTION
The 2023 WGW Utility Standards shall govern the requirements for design and construction of all water, gas,
and wastewater utilities within the City of Palo Alto’s public right-of-way. All drawings and specifications for
City projects or private development projects within the public right-of-way shall conform to 2023 WGW Utility
Standards, unless otherwise approved by the WGW Engineering Manager. Private utilities on private
properties fall under the jurisdiction of the City’s Planning Department, Building Inspection Division. A new
edition of the WGW Utility Standards is anticipated to be issued annually. The electronic downloadable file is
available at City of Palo Alto Utilities Engineering website:
https://www.cityofpaloalto.org/files/assets/public/utilities/utilities-engineering/general-specifications/2024-
wgw-utility-standards_online-version.pdf
Dean Batchelor Matt Zucca, P.E.
Director Assistant Director
Utilities Department Utilities WGW Engineering and Operations
Silvia Lee Santos, P.E. Aaron Perkins, P.E.
Engineering Manager Principal Engineer
Utilities Engineering/WGW Utilities Engineering/WGW
Tuan Nguyen, P.E. Nelson Schlater, P.E.
Principal Engineer Principal Engineer
Utilities Engineering/WGW Utilities Engineering/WGW
Patrick LaBruzzo, P.E. Jose Jovel
Principal Engineer Utilities Supervisor
Utilities Engineering/WGW Utilities Engineering
END OF SECTION
TABLE OF CONTENTS WGW UTILITY STANDARDS
CITY OF PALO ALTO PAGE 1
Table of Contents
WGW Utility Standards
Technical Specifications
Section No. Title
Section 800 Additional Provisions for Utilities Contractors
Section 860 Street Pavement Schedule – Example
Section 870 Policy and Procedures for Water Use
Section 1500 Site and Traffic Control for WGW Utilities Contractors
Section 2200 Excavation, Backfill, and Restoration
Section 2300 Polyethylene Pipe Installation for WGW
Section 2400 Fusion Procedures and Certification for Water and Sewer
Section 2500 Fusion Procedures and Certification for Gas
Section 2660 Water Design and Construction Standards
Section 2685 Natural Gas Distribution System
Section 2730 Wastewater Design and Construction Standards
Section 2731 Vitrified Clay Sewer Pipe
Section 2733 Polyvinyl Chloride Sewer Pipe
Section 2735 Sewer Construction with Polyethylene Pipe
Section 2735-1 Form for Open Trench Contractor/Subcontractor Experience
Section 2735-2 Form for Open Trench Superintendent/Foreman Experience
Section 2735-3 Form for Pipe-Bursting Contractor/Subcontractor Experience
Section 2735-4 Form for Pipe-Bursting Superintendent/Foreman Experience
Section 2736 Cured-in-Place Pipe (CIPP)
Section 2736-1 Form for CIPP Contractor/Subcontractor Experience
Section 2736-2 Form for CIPP Superintendent/Foreman Experience
Section 2737 Sanitary Sewer Lateral
Section 2738 Concrete Manholes
Section 2739 Cleaning and Video Inspection of Sewer Pipe
Section 2740 Survey Data Collection
Section 2741 Legacy Cross Bore Inspection Guidelines
Appendices
Appendix A General WGW Utility Standard Details
Appendix B Water Standard Details
Appendix C Gas Standard Details
Appendix D Wastewater Standard Details
3
TABLE OF CONTENTS TECHNICAL SPECIFICATIONS
CITY OF PALO ALTO PAGE 1
Table of Contents
Technical Specifications
Section No. Title
Section 800 Additional Provisions for Utilities Contractors
Section 860 Street Pavement Schedule - Example
Section 870 Policy and Procedures for Water Use
Section 1500 Site and Traffic Control for WGW Utilities Contractors
Section 2200 Excavation, Backfill, and Restoration
Section 2300 Polyethylene Pipe Installation for WGW
Section 2400 Fusion Procedures and Certification for Water and Sewer
Section 2500 Fusion Procedures and Certification for Gas
Section 2660 Water Design and Construction Standards
Section 2685 Natural Gas Distribution System
Section 2730 Wastewater Design and Construction Standards
Section 2731 Vitrified Clay Sewer Pipe
Section 2733 Polyvinyl Chloride Sewer Pipe
Section 2735 Sewer Construction with Polyethylene Pipe
Section 2735-1 Form for Open Trench Contractor/Subcontractor Experience
Section 2735-2 Form for Open Trench Superintendent/Foreman Experience
Section 2735-3 Form for Pipe-Bursting Contractor/Subcontractor Experience
Section 2735-4 Form for Pipe-Bursting Superintendent/Foreman Experience
Section 2736 Cured-in-Place Pipe (CIPP)
Section 2736-1 Form for CIPP Contractor/Subcontractor Experience
Section 2736-2 Form for CIPP Superintendent/Foreman Experience
Section 2737 Sanitary Sewer Lateral
Section 2738 Concrete Manholes
Section 2739 Cleaning and Video Inspection of Sewer Pipe
Section 2740 Survey Data Collection
Section 2741 Legacy Cross Bore Inspection Guidelines
4
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 1
SECTION 800
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS
PART 1 – GENERAL
1.01 DESCRIPTION
The additional provisions in this section apply to work on Utilities Capital Improvement Projects
(CIP).
1.02 DEFINITIONS
Capitalized terms which are not otherwise defined in these Standards have the same meaning
provided in Article 1 of the City’s General Conditions.
1.03 COST SAVINGS INCENTIVE
The Contractor may suggest contract cost savings changes by means of a contract cost savings
proposal (CCSP). If these changes are approved by the City as deductive change orders, the
contract cost savings shall be shared by the Contractor and City, as long as the proposed change
is of equal or greater performance that meets the original design’s performance goal(s). The
sharing of cost savings shall be 50 percent to the Contractor and 50 percent to the City. The City's
cost for reviewing the Contractor's suggested savings shall include the cost of engineering services
for evaluation of proposals and cost of required redesign. The City's total cost for all reviews of
Contractor proposals shall be deducted from the total cost savings to be shared.
The Contractor may suggest savings at any time during the contract period. The Engineer will
evaluate Contractor-suggested cost savings and the City will make a decision as to whether or not
to make the change.
At a minimum, the Contractor shall include in each CCSP the following information:
A. A description of the difference between the existing contract requirement and the proposed
change. The comparative advantages and disadvantages of each, a justification of the
alteration of an item's function or characteristics, and the effect of the change on the item's
performance.
B. A list and analysis of the contract requirements that must be changed if the CCSP is
accepted, including any suggested revisions to the project specifications.
C. A separate, detailed cost estimate for (a) the affected portions of the existing contract
requirement and (b) the CCSP shall be submitted. The cost reduction associated with the
CCSP, shall take into account the Contractor's development and implementation costs as set
forth in the City Standard Drawings and Specifications, including any amount attributable to
subcontracts.
D. A statement of the time by which a contract modification accepting the CCSP must be issued
in order to achieve the maximum cost reduction, noting any effect on the contract completion
time or delivery schedule.
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ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 2
The Engineer will process CCSP's expeditiously, however, in no case will a deductive change order,
proposed during the time period or later in the project, be the basis of a time extension.
If the CCSP is not accepted, the Engineer will notify the Contractor in writing, explaining the reasons
for rejection. The Contractor may withdraw any CCSP, in whole or in part, at any time before it is
acted upon by the Engineer.
1.04 TYPICAL TIMELINE AND CONTRACTOR REQUIREMENTS FOR NOTICE OF AWARD,
CONTRACT EXECUTION, NOTICE TO PROCEED, PRE-CONSTRUCTION SUBMITTALS, PRE-
CONSTRUCTION CONFERENCE, AND COMMENCEMENT OF WORK
The typical or anticipated times provided for City actions in this section are provided solely for the
Contractor’s convenience, and will not be binding against the City since the actual time for the City’s
action may vary depending on applicable circumstances.
A. The Notice of Award typically is issued within ten (10) business days of the City-Council
approval date.
B. Per IFB Part 2 Instructions to Bidders Section 9.3, the Contractor must submit all required
documentation, including, without limitation, all bonds and evidence of insurance within ten (10)
business days of the date of issuance of the Notice of Award.
C. The Notice to Proceed is anticipated to be issued within twenty (20) business days from the
Notice of Award and when the Contract is fully executed. The Notice to Proceed may specify
the pre-construction submittal due date, pre-construction conference date, and the anticipated
project commencement date.
D. The Contractor must submit all pre-construction submittals, as specified in the Contract
Documents or listed in the Construction Submittal List in IFB Appendices, for City’s
approval within ten (10) business days from the Notice to Proceed issuance date.
E. The pre-construction conference is anticipated to be scheduled for 20 days after the pre-
construction submittal deadline.
F. The commencement of work date is anticipated to be 10 days after the pre-construction
conference, when pre-construction submittals are substantially or completely approved.
1.05 SUBMITTALS
In addition to complying with the general submittal requirements in Section 3.12 of the General
Conditions, Contractor must meet any specified project milestones by submitting required pre-
construction submittals in advance to avoid delays due to submittal review or material lead time.
As further specified in Section 6.4 of the Construction Contract, liquidated damages may be
assessed if the Contractor fails to meet specified project milestones. All pre-construction submittals
must be approved prior to delivery of the material/equipment to the job site that the submittal relates
to or starting the portion of work. Unless specifically stated elsewhere in the Contract
Specifications, the Contractor shall make submittals in advance of ordering the materials to provide
sufficient time for review, approval, possible revisions and re-submittals, and placing
orders/securing delivery.
Ultimate responsibility for the accuracy and completeness of the information contained in each
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ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 3
submittal shall remain with the Contractor. Unless otherwise specified, make submittals in groups
containing all associated items to assure that required information is available for checking when
the submittal is received. Partial submittals may be rejected as not complying with the provisions
of the Contract and the Contractor may be held liable for delays so occasioned. The Engineer will
supply a checklist of items that shall be submitted by the Contractor for approval.
If the submittal is returned to the Contractor marked "NO EXCEPTIONS TAKEN", "MAKE
CORRECTIONS NOTED", or “RECEIPT ACKNOWLEDGED”, formal revision and resubmission of
the submittal will not be required. Fabrication of any item shall not commence before the Engineer
has reviewed the pertinent submittals and returned copies to the Contractor marked "NO
EXCEPTIONS TAKEN" or “MAKE CORRECTIONS NOTED.”
If the submittal is returned to the Contractor marked "REVISE AND RESUBMIT" or "REJECTED",
the Contractor shall, within five (5) business days, make a complete and acceptable submittal to
the Engineer by the second submission of a submittal item. When material is resubmitted for any
reason, transmit under a new letter of transmittal and with a new transmittal number; on re-
submittals, cite the original submittal number for reference.
Revisions indicated on submittals shall be considered as changes necessary to meet the
requirements of the contract and shall not be taken as the basis of claims for extra work. If the
Contractor considers any required revision to be a change, he shall so notify the Engineer as
provided for in the General Conditions.
The Contractor shall maintain an accurate submittal log for the duration of the Work, showing
current status of all submittals at all times, and keep it available to the Engineer for his review upon
request.
Where contents of submitted literature from manufacturers include data not pertinent to the
submittal, clearly show which portions of the contents are being submitted for review.
The Engineer's review of the Contractor's submittals shall not relieve the Contractor of the entire
responsibility for the correctness of details and dimensions. The Contractor shall assume all
responsibility and risk for any work not conforming to the contract. Any fabrication or other work
performed in advance of the receipt of approved submittals shall be entirely at the Contractor's risk
and expense.
1.06 MEETINGS
A. Pre-Construction Conference/Meeting
City will conduct a mandatory pre-construction meeting when pre-construction
submittals are substantially or completely approved, typically 20 business days after the
pre-construction submittal due date. The pre-construction submittal due date is 10 business
days from the Notice to Proceed issuance date per Section 1.04.D. The Contractor’s
primary representative and its Superintendent for the project must attend the meeting, which
will include discussion of the scope of work, sequence of operations, project milestones if
appropriate, and project requirements. The Contractor may include other supervisory
personnel and representatives from key subcontractors as well.
Work on the project cannot commence until all required pre-construction submittals
have been approved by the City. Contractor will be solely responsible for delay in
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ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 4
authorizing commencement of the work by the planned project start date, milestones, or
completion date due to Contractor’s failure to provide all pre-construction submittals as
specified.
B. Project Meetings
Following commencement of the work, Contractor’s Superintendent must attend and
participate in regular weekly project meetings as scheduled by the Engineer. The
Subcontractor and supplier representatives may only attend the regular project meetings when
specifically invited by the Engineer.
The meetings will be conducted by the Engineer, and the Engineer will keep minutes of the
proceedings.
The Engineer will establish the agenda for each project meeting, which may include matters
including, but not limited to, reports on construction progress, the status of submittal reviews,
the status of record drawings, progress payment requests, the status of information requests,
and any general business.
1.07 SCHEDULE UPDATE
A. In addition to the monthly schedule requirements in Section 3.10.3 of the General Conditions,
one day prior to each weekly project meeting, Contractor must submit to Engineer an updated
and detailed rolling 3-week look-ahead schedule, that is tied to the overall construction
schedule.
It is imperative that the schedule be kept up to date. At any time during the progress of the
work, the Engineer may request an updated or revised construction schedule if there is
evidence that progress is lagging by a week or more from the last submitted schedule. The
Contractor shall provide such updated or revised schedule within two (2) Working Days.
B. It is the Contractor's responsibility to keep the Engineer continually informed as to the location
and timing of all the work. Prior to starting each day’s work, the Contractor shall email the
planned work for the day, including road or lane closures, to the Inspector and Engineer.
1.08 NOTIFICATION
The Contractor shall provide written notification of the work to abutting property owners at least
fifteen (15) Days and again 24 hours prior to commencing work at their specific locations. If the
driveway to any garage or parking area is to be closed for work, the notice shall state the
approximate time of work in the driveway and when the work area will be reopened. No overnight
closure of any driveway will be permitted.
1.09 ON-SITE SUPERVISION
A contractor’s superintendent or foreman, or designated superintendent or foreman, is required to
be physically on-site the entire day for the duration of the Work to supervise all construction
activities. Substitution of superintendents or foremen shall be approved by the Engineer.
Any superintendent/foreman expected to perform polyethylene pipe fusion shall be tested and
qualified in accordance with Section 2300 Polyethylene Pipe Installation (2.02.H.2).
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ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 5
1.10 PROGRESS PAYMENT
In addition to the provisions of Article 9 of the General Conditions, including Section 9.2 on progress
payments, Applications for Payment for Utilities Capital Improvement Program (CIP) projects must
also list the locations where the work was performed, including names of streets with reference to
the Project drawings and corresponding station numbers. All addresses of service lines, installed
or reconnected, and locations of other invoiced items must be also included in the invoice.
The Application for Payment must include all of the following:
A. GPS survey data collected and furnished in accordance with requirements stated in Section
2740 of these specifications for infrastructure installed within the pay period stated on the
invoice. The Contractor shall submit the GPS data set collected for the installation work during
the first week of construction and subsequently every month, with or without an invoice, for the
City to validate its accuracy.
B. The completeness and accuracy of GPS survey data shall be verified by the City before the
issuance of each payment to the contractor. If the GPS survey data is found incomplete or
inaccurate, the City may require the Contractor, at Contractor’s own expense, to reopen or
uncover GPS surveyed infrastructure/objects and perform new survey if the accuracy of the
originally submitted data is not in compliance with these specifications. The Contractor will be
required to perform surface restoration, at the Contractor’s own expense, following the
additional survey.
C. Submission of checklists of all notified affected property owners (15 day and 24-hour notices).
D. Submission of data logger and electrofusion records.
E. Video on USB flash drive, hard drive, or provided through a Cloud platform of post construction
sewer main and/or lateral video as specified in these Specifications for pay period stated on
the invoice (if applicable).
F. List of quantities verified by City Inspection.
G. Updated construction schedule as specified in Section 3.10 of the General Conditions.
H. Additional items (special requirements) as stated below:
1. Water CIP Projects:
a. A successful hydrostatic pressure/leak and bacteriological test, as specified in Section
2660 of these specifications, of the water system installed in the pay period stated on
the invoice.
2. Gas CIP Projects:
a. A successful pressure test of the gas system installed in the pay period stated on the
invoice.
b. Submission of an attached CIP Gas Main Replacement Project Polyethylene Gas Pipe
Fusion Records Form and automated fusion machine data printouts.
c. Records of bore logs.
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ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 6
d. Pre and post construction sewer lateral/main cross bore verification completed,
submitted, and accepted in accordance with the procedures stated in Sections 2739
and 2741 of these specifications.
3. Wastewater CIP Projects:
a. All sewer main/lateral post-construction CCTV inspection per Section 2739.
PART 2 – QUALITY CONTROL
2.01 DESCRIPTION
A. Work Included:
1. Qualifications of workmen
2. Codes and Standards
3. Testing
4. Equipment and materials
5. Inspection and approval of work
6. Manufacturers' recommendations
B. Related Work: Requirements for testing are described in various Sections of the Contract
Specifications.
2.02 QUALIFICATIONS OF CONTRACTOR PERSONNEL
Provide workers in sufficient number who are thoroughly trained and experienced in the skills
required. They shall be completely familiar with the work requirements and construction methods
to complete the work described for each respective Section. A supervisor and competent person
shall be present at all times during progress of the work of each respective Section and shall direct
all work performed under each respective Section.
Contractor personnel performing polyethylene pipe fusion must produce documentation from a pipe
supplier stating their qualification to perform said work and shall be tested by the City for certification
to fuse on City piping per Section 2300 of these specifications. See Sections 2400 and 2500 for
fusion procedures and certification on water, gas, and wastewater facilities.
Workers performing work on natural gas facility shall be tested by the City for the certification per
Section 2685.3.07 Operator Qualification Requirements.
Contractor personnel performing directional drilling operations on State of California property,
involving a State of California permit, or falling under the authority of the State of California (Caltrans
Right-Of-Way) must provide proof-of-training certification acceptable to Caltrans.
Contractor personnel performing pipe-bursting work shall comply to Section 2735 for qualification
requirements.
Contractor personnel performing work within Caltrain Property are required to have successfully
completed, within the last twelve (12) months, Caltrain’s Roadway Worker Protection training
program. The Contractor shall forward to Caltrain records of those who successfully completed
the course. The Contractor shall, at all time, comply with provisions of the Federal Rail
Administration Regulation 49CFR214 (Roadway Worker Protection), the Caltrain/Amtrak Zero
10
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 7
Tolerance Policy, and the Permittor (Licensor) On-Track Safety Program.
2.03 CODES AND STANDARDS
The following reference standards (latest version) in addition to the Project Plans and
Specifications are hereby incorporated by reference and shall be referred to in this specification
by their abbreviations. These reference standards shall apply to all applicable work of this contract.
A. PUBLIC WORKS STANDARD DRAWINGS AND SPECIFICATIONS: The latest edition of City of
Palo Alto Public Works Standard Drawings and Specifications (The electronic downloadable file is
available at https://www.cityofpaloalto.org/Departments/Public-Works/Engineering-Services/Public-Works-
Standard-Drawings-and-Specifications).
B. WATER, GAS, AND WASTEWATER UTILITY STANDARDS: The latest edition of City of Palo
Alto Water, Gas, and Wastewater Utility Standards (The electronic downloadable file is available
at https://www.cityofpaloalto.org/Departments/Utilities/Utilities-Services-Safety/Engineering-and-
Operations).
C. CITY OF PALO ALTO TRAFFIC CONTROL MANUAL: The latest edition of the Traffic Control
Requirements is available at https://www.cityofpaloalto.org/files/assets/public/public-works/engineering-
services/webpages/forms-and-permits/other-guidelines/requirements-for-traffic-control-plan-submission-
2021.pdf.
D. MANUAL ON UNIFORM TRAFFIC CONTROL DEVICES (MUTCD) – CALTRANS
E. WORK AREA TRAFFIC CONTROL HANDBOOK (WATCH BOOK)
BNI Publications Inc.
F. Tree Technical Manual
Department of Planning and Community Environment, latest edition
G. U.S. DEPARTMENT OF TRANSPORTATION, PIPELINE SAFETY REGULATIONS, PARTS 190
TO 199. Copies of these regulations are available for purchase from the following address:
Transportation Safety Institute
Pipeline Safety Division DMA-607
6500 S. MacArthur Blvd.
Oklahoma City, OK 73125
H. OSHA Consultation and Compliance Section
U.S. Department Of Labor
Occupational Safety and Health Administration
71 Stevenson St. Suite 415
San Francisco, California 94105
I. CAL-OSHA
Department of Industrial Relations
State of California
Occupational Safety and Health Administrations
525 Golden Gate Ave.
San Francisco, CA 94102
11
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 8
J. UPC
Uniform Plumbing Code
20001 Walnut Drive South
Walnut, CA 91789-2825
K. UBC
Uniform Building Code
5360 South Workman Mill Road
Whittier, CA 90601
L. NEC
National Electric Code
National Fire Protection Association
Batterymarch Park
Quincy, MA 02269
M. UFC
Uniform Fire Code
5360 South Workman Mill Road
Whittier, CA 90601
N. UL
Underwriters Laboratories
1655 Scott Boulevard
Santa Clara, CA 95050
O. AWWA
American Water Works Association
6666 West Quincy Avenue
Denver, CO 80235-3098
P. NSF
National Sanitary Foundation
789 Dixboro Road
Ann Arbor, MI 48113-0140
2.04 TESTING
A. Code Compliance Testing: Inspections and tests required by codes or ordinances, or by a plan
approval authority, and which are made by a legally constituted authority, shall be the
responsibility of and shall be paid for by the Contractor, unless otherwise provided in the
Contract Documents.
B. Contractor's Convenience Testing: Inspection and testing performed exclusively for the
Contractor’s convenience shall be the sole responsibility of the Contractor.
C. Provide "Certificates of Compliance" when required and other testing and inspecting as are
specified to be furnished by the Contractor in this Section and/or elsewhere in the Contract
Documents.
D. Testing, when required, will be in accordance with the selected standards of the American
12
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 9
Society for Testing and Materials (ASTM).
E. The testing laboratory will be qualified subject to the CITY's approval.
PART 3 - PRODUCTS
3.01 EQUIPMENT AND MATERIALS
All equipment and materials furnished shall be new and the best of their respective kinds, free from
all defects and as specified in the Drawings and Specifications or as approved and accepted in
writing by the Engineer.
All equipment, materials, and devices shall be installed in accordance with the recommendations
of the manufacturer, unless otherwise approved by the Engineer. Prior to the start of work, the
Contractor shall obtain and deliver copies to the Engineer of all installation manuals, brochures,
and procedures that the manufacturer issues for the items supplied.
For projects with specific start or completion dates, it is the Contractor’s responsibility to include
necessary costs to expediate the delivery of any long-lead items to avoid delays and comply with
project specifications.
3.02 EXCESS MATERIALS
The Contractor shall return all salvageable fire hydrants and meter box lids to the City’s Municipal
Service Center. Any excess materials shall be returned to their appropriate suppliers. At no time
shall excess materials be dropped off at the City’s Municipal Service Center. All transportation and
re-stocking fees (invoice required) will be paid to the Contractor only if the City authorized the work
to be canceled. The Contractor will not be paid for excess materials that are over-ordered and/or
purchased without approved submittals.
PART 4 - EXECUTION
4.01 APPROVAL OF WORK
All work to be performed and all material to be furnished by the Contractor shall be subject to
inspection by the Engineer at any time and shall be performed and furnished to their satisfaction.
Any work concealed before it has been inspected by the Engineer or their representative shall, at
the request of the Engineer, be reopened or uncovered. If deficiencies are found, these
deficiencies shall be corrected at the Contractor’s expense.
The City reserves the right to inspect materials or equipment during the production, manufacturing
or fabricating process, or before shipment.
Neither acceptance of the Work, nor final payment, shall relieve the Contractor of the responsibility
for performing the Work in accordance with the Contract requirements. The Contractor shall
remedy any work not conforming to the Contract without expense to the City.
4.02 MANUFACTURER'S RECOMMENDATIONS
Whether specifically mentioned or not in the Drawings or Specifications, all equipment, materials,
devices, etc., shall be installed in a manner meeting the manufacturer's recommendations for the
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ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 10
particular item. Prior to the start of work, the Contractor shall obtain and deliver copies to the
Engineer of all installation manuals, brochures, and procedures that the manufacturer issues for
the items supplied. The Contractor shall be held responsible for all installation contrary to the
manufacturer's recommendations, unless otherwise approved by the Engineer. If any item or piece
of equipment or material is found to be installed not in accordance with the manufacturer's
recommendations, or as otherwise directed by the Engineer, the Contractor shall make all
necessary changes and revisions to achieve such compliance at the Contractor's expense.
4.03 COOPERATION WITH TESTING LABORATORY
A. Representatives of the testing laboratory shall have access to the Work at all times and all
locations where the Work is in progress. Contractor shall provide such access to enable the
laboratory to perform its functions properly.
B. Cooperate with the City's selected testing agency and all others responsible for testing and
inspecting the Work.
4.04 TAKING SPECIMENS
All specimens and samples for testing, unless otherwise provided in the Contract Documents, shall
be taken by the testing personnel. All sampling equipment and personnel will be provided by the
testing laboratory. All deliveries of specimens and samples to the testing laboratory will be
performed by the testing laboratory.
4.05 PRODUCT HANDLING
Contractor shall promptly process and distribute required copies of test reports and related
instructions for the "Certificate of Compliance" to allow necessary retesting and/or replacement of
materials with the least possible delay in progress of the Work.
4.06 SCHEDULES FOR TESTING
A. Establishing Schedule:
1. By advance discussion with the testing laboratory selected by the City, determine the time
required for the laboratory to perform its tests and to issue each of its findings.
2. Provide no less than 48-hour notice to the Engineer when testing will be required and
provide all required time within the construction schedule to perform necessary testing.
B. Revising schedule: When changes of construction schedule are necessary during construction,
Contractor shall coordinate all such changes with the testing laboratory as required.
C. Adherence to Schedule: If the testing laboratory is prevented from testing or taking specimens
due to incompleteness of the Work, all extra charges for testing attributable to the delay will be
back-charged to the Contractor and shall not be borne by the City.
4.07 PAYMENT FOR TESTING
Contractor shall pay for all testing (excluding soil compaction testing) and re-testing required to
comply with the Contract Specifications, Codes, Regulations, and all other applicable laws.
14
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 11
Contractor is responsible to pay for the soil compaction testing technician’s waiting time if the trench
backfill is not ready to be tested at the scheduled time. Contractor shall also pay for the soil
compaction testing technician’s time to re-test if the test fails. Progress payments will be deducted
for the hours the City is billed due to Contractor’s delay.
4.08 DAMAGE TO PUBLIC OR PRIVATE PROPERTY
Damage to public or private property shall be repaired in kind or as the Engineer shall direct, at the
Contractor's expense. This includes, but not limited to the repair or replacement of streets,
sidewalks, underground utilities, City monuments, traffic facilities, traffic loop detectors, striping,
legends, signals, signs, pavement markers, trees, and landscaped areas. Temporary traffic
markers shall be placed immediately after final paving to properly channel traffic.
If damage to utilities occurs beyond the City’s Right-of-Way, the Contractor shall coordinate with
the City’s Building Division to acquire permits and schedule on-site inspection. The Contractor is
responsible for all costs associated with the repair, inspection, and permits for the restoration of
on-site plumbing. Visit https://www.cityofpaloalto.org/gov/depts/ds/default.asp to acquire permits
or schedule inspection.
4.09 WORK OUTSIDE OF PUBLIC RIGHT OF WAY
Project specified work that is outside the public right-of-way shall be conducted with care and
consideration consistent with the requirements of these Specifications, Public Works Standard
Drawings and Specifications, and/or Building Code including other referenced standards of this
specification. The Contractor is prohibited from advertising its services to the owners/residents of
properties and businesses affected by the project construction for the duration of the Contract.
For work on private property, it is the Contractor’s responsibility to contact the owner or occupant
to coordinate the schedule and access. Sufficient notification shall be provided by the Contractor
to the owner or occupant to avoid delays.
4.10 MONUMENT REPLACEMENT
All monuments within the project site shall be preserved as required by the State and local
regulations. Damaged or destroyed monuments shall be replaced by a California licensed Land
Surveyor hired by the Contractor. The Contractor shall submit the method and procedures of tying
out the monuments for the City Surveyor’s approval. The Contractor shall also provide a recorded
copy of the “corner record” to the City Surveyor. No separate bid item was made for the cost of any
surveying or monument replacement work. The cost shall be included in one or more of the bid
items.
4.11 METERED OR PERMIT-REQUIRED PARKING
The Contractor is responsible for obtaining and paying (not compensated by the City) for all
metered parking or permit-required parking spaces occupied by contractor’s personal vehicles
inside or outside of the immediate construction zones. The contractor is also responsible to pay for
any metered parking or permit-required parking spaces made unavailable by construction
equipment, vehicles, or material during non-working hours or outside the immediate construction
zone(s).
15
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 12
4.12 Photos/Video of Existing Site Condition
The Contractor shall take photos and video of existing jobsite conditions and temporary storage
areas prior to the commencement of work. The Contractor shall be responsible for site restoration
to pre-construction conditions if the damage is caused by the Contractor’s work or storage. If the
Contractor fails to document existing condition of public or private properties prior to construction,
the Contractor will be held liable for any damage sustained at the construction sites or storage
areas.
4.13 Reporting Requirements of Sanitary Sewer Overflows (SSOs)
x In the event of a SSO that is observed or created by the Contractor, the Contractor will immediately notify the City’s Dispatch by calling 650-329-2413 and the assigned City
Inspector. x The following information should be reported to the City’s Dispatch: location of the SSO, contact information of the Contractor representative and City Inspector, time Contractor first
noticed the SSO, and if SSO is occurring at the time of the call. x Utility Dispatch may contact Wastewater Operations to respond. x The Contractor must take appropriate steps to stop, contain, or divert the SSO by using
absorbent, portable dams, sandbags, or by-pass equipment. x The responding Operations’ crew may assist the Contractor with stopping, containment, or diversion of SSOs and complete field reports associated with the SSO.
END OF SECTION
16
STREET PAVEMENT SCHEDULE - EXAMPLE SECTION 860
CITY OF PALO ALTO Section 860 PAGE 1
SECTION 860
STREET PAVEMENT SCHEDULE
Surface restoration shall include all materials and labor required to restore the area both below and above
ground. Restoration of pavement sections, sidewalks, driveways, landscaping, curbs and gutters, and backfill
shall conform the City Standard Drawings and Specifications, latest version adopted. The pavement restoration
shall be as per City’s restoration requirements and in accordance with the Public Works Department Standard Drawings
and Specifications and Project Drawings.
Existing Pavement Section Table (Example)
Legend for Surface Type:
AB2 – Aggregate Base (Class 2)
AC – Asphalt Concrete
CRB – Crusher Run Base
DLAC – Deep Lift Asphalt Concrete
PCC – Portland Cement Concrete
The pavement thickness type information provided above may not represent 100% of the actual pavement
thickness in the project areas. For bidding purposes, the Contractor shall assume the minimum required
thickness from the CPA Standard Specifications if the information is not available. For bidding purposes, the
Contractor shall assume additional pavement thickness of up to 25% from the data provided and the CPA
Standard Specifications, whichever is greater.
For restoration within other agencies’ right-of-way, the Contractor shall contact and follow the direction and
requirements of the permitting agency.
The cost of pavement restoration shall be included in one or more of the bid items. If the discrepancy occurs
between the proposed section and the actual pavement thickness, the Engineer shall be informed to verify the
existing pavement thickness. The pavement shall be restored “in-kind” meeting the minimum requirement per
CPA Standard Specifications.
END OF SECTION
SHEET NUMBER STREET BETWEEN AND SURFACE TYPE
SURFACE
THICKNESS
(INCH)
BASE TYPE
BASE
THICKNESS
(INCH)
Pavement Condition
5,6 Geng Rd Embarcadero Rd End of Geng Rd AC 3 AB2 12 Poor
7,8,9 Arboretum Rd Sand Hill Rd Orchard Ln AC 1 CRB 10 Fair/At-Risk
12 University Ave Webster St Byron St AC 4 DLAC 8 Very
Good/Excellent
17
POLICY AND PROCEDURES FOR WATER USE SECTION 870
CITY OF PALO ALTO Section 870 PAGE 1
SECTION 870
POLICY AND PROCEDURES FOR WATER USE
PART 1 - GENERAL
1.01 GENERAL
Reclaimed water shall be used for backfill compaction, and cleaning and testing of manholes. An
overhead standpipe with a five hundred (500) gallon per minute (gpm) fill rate is available at the Palo
Alto Regional Water Quality Control Plant (RWQCP) between Monday through Friday, 6:30 a.m. to
5:00 p.m., except on public holidays. A recycled hydrant is also available for 24-hours a day, 7-days a
week to active permit holders and is located at Greer Park, near 1198 Colorado Avenue, Palo Alto,
CA. This will allow self-service pickup and use of reclaimed water on a first come-first serve basis, up
to the capacity of the reclamation plant of four and a half (4.5) million gallons per day (MGD).
The permit may be obtained on the City’s website at:
https://www.cityofpaloalto.org/files/assets/public/public-works/water-quality-control-plant/recycled-
water/2021/9.-user-guidelines-and-application.pdf and shall be submitted to the RWQCP at 2501
Embarcadero Way, Palo Alto, CA with a $50 check or money order payable to the “City of Palo
Alto”. For additional information, call 650.329.2598 or e-mail recycledwater@cityofpaloalto.org
City Contractors are required to provide their company’s Certificate of Liability Insurance as part of
the requirements for applying for a permit to claim recycled water. Applicants can request a multi-
year permit for multi-year projects for the City of Palo Alto. Permits for recycled water expire every
year end (December 31st) regardless of application date except for multiyear permits.
The City of Mountain View operates reclaimed water-filling hydrants at the end of Crittenden Lane (E.
of N. Shoreline Boulevard), and at Marine Way near Coast Avenue in Mountain View, CA. A key
deposit is required. Contact the City of Mountain View at (650) 903-6329 or at
recycledwater@mountainview.gov
Potable water for drinking, filling of water mains, etc. is available from hydrants in the vicinity of the
work. Hydrant water shall be metered with a hydrant meter obtained by contacting the City of Palo
Alto Utilities Business Office at (650) 329-2161 (Ground Floor Civic Center, 250 Hamilton Avenue,
Palo Alto). A meter deposit is required. Payment for potable water used will be deducted from the
Contractor's deposit at the time the meter is returned. Refer to the Policy and Procedures for Water
Hydrant Meter Use, for more information.
All costs and expenses for any water used on the project shall be included in one or more of the Bid
items and no extra compensation shall be paid to the Contractor for water.
PART 2 - POLICY AND PROCEDURES FOR WATER HYDRANT METER USE
2.01 USE RECLAIMED WATER WHENEVER POSSIBLE
The water consumption ordinance for the City of Palo Alto requires the review of water use for
construction purposes, to encourage the use of reclaimed water. The use of a reasonable amount of
potable water, for flushing potable water pipes, for instance, is still permissible through hydrant
meters. However, substantial water needs for construction purposes must be met with reclaimed
water.
Reclaimed water will be required for the following projects:
18
POLICY AND PROCEDURES FOR WATER USE SECTION 870
CITY OF PALO ALTO Section 870 PAGE 2
1. Grading projects, i.e. road construction, paving, site development, and projects reviewed by
the Water/Gas/Wastewater Division.
2. Street washing and flushing for final project clean-up.
3. Projects for which daily water use exceeds 5,000 gallons.
4. Projects for which weekly water use exceeds 25,000 gallons.
Procedures for permission to connect to City of Palo Alto hydrants and the penalties for not using the
hydrant meter properly are explained below.
Exceptions to this policy typically are granted only for very small jobs. Requests for exceptions to this
policy will be referred to the Senior Engineer in the Water/Gas/Wastewater Division for review and
determination.
2.02 HOW YOU CAN GET A HYDRANT METER
Applicants for a water hydrant use permit should come in person to the Utilities Department
Customer Service Center, 250 Hamilton Avenue, Ground Floor. At that time:
1. Complete a questionnaire about your project and its location.
2. Pay the $750 meter deposit fee.
3. Get six meter reading cards. NOTE: On or before the 25th day of each month, a card should
be completed with the current meter reading and sent to the Customer Service Center.
4. You will then be given a form to take to the Municipal Services Center (MSC) at 3201 East
Bayshore Road where you may pick up a hydrant meter. You will be assigned the meter for a
period of six (6) months. At the end of that time the meter must be returned to the MSC. If
you need potable water for the same project site after the three months, a new meter will be
issued. Included with the hydrant meter will be an instruction sheet for proper use of the
meter. By taking the meter, it is assumed that you will properly use the meter at all
times when connecting to City hydrants.
2.03 PENALTIES
By providing an applicant with hydrant meters for use of potable water at construction sites, the City
of Palo Alto is entering into a relationship of trust with the applicant. Nevertheless, City staff will, from
time to time, visit the site to ensure that the hydrant meter is being used and that it is being used
correctly. Failure to comply with any of the above rules or to properly hook up the meter according to
the instruction sheet provided with the hydrant meter, may subject the applicant to penalties.
Specifically:
A. Failure to use the hydrant meter or to use it so that water does not pass through the meter when
drawing water from a City of Palo Alto hydrant will result in fines of $50.00 per day and possible
forfeiture of all or part of the deposit, revocation of the permit, and prosecution according to the
law (Rule and Regulation 21.D.1.b.i; 21.D.1.b.iv; and 8.C.1-2).
B. Failure to submit meter-reading cards monthly and in a timely manner may result in forfeiture of
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POLICY AND PROCEDURES FOR WATER USE SECTION 870
CITY OF PALO ALTO Section 870 PAGE 3
all or part of the deposit.
C. Failure to return the hydrant meter at the end of the three-month period may result in fines of
$50.00 per day and/or part of the deposit.
20
POLICY AND PROCEDURES FOR WATER USE SECTION 870
CITY OF PALO ALTO Section 870 PAGE 4
2.04 HYDRANT METER QUESTIONNAIRE (SAMPLE)
The following is a sample copy of the City’s Hydrant Meter Questionnaire.
HYDRANT NUMBER __________________
HYDRANT METER QUESTIONNAIRE
NAME:
BILLING ADDRESS: ___________________________________________________________
TYPE OF BUSINESS:
TYPE OF PROJECT:
PROJECT ADDRESS:
HOW WILL WATER
BE USED?
IN WHAT QUANTITY?
FOR HOW LONG?
(CIRCLE ONE)
Does your company own a truck? YES NO
Will a water truck be used on the project? YES NO
What is the capacity of the truck (in gallons)?
"SPECIAL WATER UTILITY REGULATIONS, Rule and Regulation 21, Paragraph B. 1, B. 3."
Failure to return the hydrant meter at the end of the appropriate period may result in additional
charges of $ 50.00 per day.
Have customer read this paragraph and sign for verification.
Signature Title Date
21
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 1
SECTION 1500
SITE AND TRAFFIC CONTROL
FOR WGW UTILITIES CONTRACTS
1.01 DESCRIPTION
Work Included in this section:
x Traffic Control
x Safety
x Sanitation Facilities
x Storage of Equipment and Materials
x Cleanup
x Signage
1.02 TRAFFIC CONTROL
A. General
All traffic control, depending on location of work and area of jurisdiction, shall be performed in strict
compliance with City of Palo Alto Transportation Division per the requirements noted herein,
CALTRANS, and/or Santa Clara County traffic control requirements where applicable.
All Utilities CIP projects, irrespective of the requirements set forth by the authority having jurisdiction
over traffic control, must have a traffic control plan. These plans are mandatory for all on-site work
and need to be signed and stamped by a California registered professional traffic engineer.
B. Additional Traffic Control Requirements
In addition to the requirements in Transportation Department’s ‘Requirements for Traffic Control
Plan Submission’ manual, all traffic control requirements outlined in this section shall also be
followed. The contractor shall furnish, erect, and maintain sufficient warning and directions signs,
working flashers on each barricade, lighted warning signs, and furnish sufficient flag persons to give
adequate warning to the public at all times in the road or street under construction.
Contractor shall submit traffic control plans, as part of the required pre-construction submittals, to
the Engineer for City’s approval within twenty (20) business days from the Notice of Award issuance
date. For projects with critical start and/or completion dates, it is the Contractor’s responsibility to
meet the requirements by submitting traffic control plans as specified and allow sufficient review
time. Liquidated damages will be assessed when Contractor fails to meet the project milestones
and/or Substantial completion.
The traffic control plan shall include a typical intersection and street for work planned with typical
pavement widths and lane widths noted on the plan. The Transportation Department requires site-
specific plans on high-volume traffic intersections and arterial streets. For major signalized
intersections and arterial/collector streets, the traffic control plan shall reflect actual (not typical)
intersection layout and indicate islands, medians, lane lines, bike lane lines, nearby driveways, and
note all pavement and lane widths. See Section 1500.1.02.B.30 for a list of arterial and collector
streets. Additional streets may be identified in the 'Requirements for Traffic Control Plan
Submission’ manual. Some major street intersections are listed below:
x All Intersections with Page Mill Road, Embarcadero Road, Arboretum Road
22
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 2
x Intersections of Charleston Road/Commercial Street and Coyote Hill Road /Hillview Avenue.
All cost and expense for traffic control shall be included in the Bid prices for various Bid items and no
special compensation shall be allowed.
Contractor shall not detour traffic without the approval of Transportation Department. ‘Closed to
through traffic’ is not permitted on two adjacent parallel streets simultaneously, unless it’s an
emergency, approved by the Engineer, and the contractor received an approved traffic detour plan
from Transportation Department.
The Contractor shall maintain adequate separation between pedestrians, bicyclists, vehicular traffic,
truck traffic, and the work site during construction by providing adequate barricades with at least one
working flasher on each, pedestrian bridges, ramps, reflectors, cones, guard rails, fencing and any
other warning devices as required. The Contractor shall separate truck traffic from bicycle traffic (i.e.
place signs directing bicyclists to an alternate route away from the haul route). Each pedestrian
crosswalk, when crossing by or over construction excavation, shall be provided with a pedestrian
bridge with handrails. The Contractor shall not remove the barricades in the street at any given
location until the final paving repair has been completed and the hazard to bicyclists and motorists
no longer exists.
The Contractor shall coordinate the Work with the appropriate Transit Districts, and School Districts
running the buses in the area and shall notify the Communications once a week about the
construction activities.
The following requirements are minimum and do not limit the Contractor's responsibility of doing all
that is practical and necessary to ensure the safety of workers, pedestrians, bicyclists, and
motorists:
1. Traffic control shall conform to the latest additions of the Manual of Uniform Traffic Control
Devices (MUTCD Caltrans), Work Area Traffic Control Handbook (WATCH BOOK),
Requirements for Traffic Control Plan Submission, and all applicable City of Palo Alto
Standards.
2. The Contractor is required to submit alternative traffic control plan(s) for day and night work.
3. Local and emergency access shall be maintained on all streets at all times.
4. The Contractor shall protect open excavations, trenches, and such during construction with
fences, covers, and railings, as required, together with signs, lights, and other warning devices
sufficient to maintain safe pedestrian, bicycle, and vehicular traffic to the satisfaction of the City.
5. After each site has been completed, the Contractor at his expense shall restore planting areas
and other areas abutting the work to the condition existing at the start of work. Unless otherwise
authorized by the City Inspector, all construction and restoration including tape striping, signing,
curb markings, etc. shall be completed within fifteen (15) working days from start of work at any
specific location.
6. The Contractor shall conduct operations and schedule cleanup so as to cause the least possible
obstruction and inconvenience to traffic, pedestrians, cyclists, and adjacent property owners. All
work areas shall be swept clean at the end of each day's work and at other times when directed
by the City. A mobile street sweeper shall be used wherever practical and as required by the
23
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 3
Project Manager, and dust shall be suppressed to the satisfaction of the City. The Contractor
shall remove all debris from the job site at the end of each work day.
7. The Contractor shall notify the abutting property owners at least 15 days in advance and again
24 hours prior to commencing work at their specific locations. The Contractor will be required
to prepare checklists of all notified affected property owners (15 day, and 24 hour
notices) and submit the lists to the Engineer prior to commencing a work at their specific
locations. The notice shall include the project title, contact person(s) and a local telephone
number, and construction dates. The notifications of the construction provided to any
School or Hospital administrations and records of any subsequent contacts with the
School or Hospital administrations, related to the construction, must be maintained and
available for inspection for no less than 5 years from the date of notification. Such
notifications must include name(s) and title(s) of person(s) contacted/notified.
8. Contractor shall maintain access to all driveways except when actually doing construction within
the driveway boundaries, at which time partial access shall be maintained unless alternate
arrangements are made with the property owners or tenants in advance. If the driveway to any
garage or parking area must be closed for construction work, the notice shall state the
approximate time it will be reopened.
9. The Contractor shall post "No Parking" signs as required 72 hours in advance. The signs shall
be approved by the City Police Department and shall specify the date and time “No Parking” will
be allowed. Signs shall be posted a maximum of 50 feet on center and removed immediately
after the work is completed. The signs shall be removed when the work is completed.
10. The Contractor is required to provide a written notification regarding bollards installation to the
affected property owners and submit a notification checklist to the Engineer.
11. The Engineer shall have the right to limit the amount of trench, which may be opened or partially
opened at any time. No more than 500 feet of trench or one City block of trench, whichever is
greater, or more than 50 potholes not to exceed a total paved surface area of 500 square feet,
shall be opened at any one time. Paved surface disruptions shall be classified as open until
final pavement resurfacing has been completed including full surface restoration on the affected
by the construction private property.
12. Temporary pavement markings shall be in place prior to allowing traffic to use the street. This
includes all markings (STOP bars, crosswalks, arrows, and lane line striping).
13. Damage done by the Contractor during the course of the work to City property shall be repaired
and restored to “like-new” condition or, as the Project Manager shall direct, at the Contractor's
expense. This includes the repair of traffic loop detectors, striping, signing, curb markings, etc.
Unless otherwise authorized by the City Inspector, all construction and restoration including
striping, signing, curb markings, etc. shall be completed within one week of work completion.
Loop detectors shall be repaired within 72 hours of damage.
14. Limited stockpiling of materials or parking of equipment during non-working hours will be
allowed on City property, i.e., streets, alleys, parking lots, sidewalks, etc. (refer to Section
1.05.A) While storing equipment and materials on the street, storage area shall be properly
barricaded and shall not block traffic. Materials shall be placed in such a manner that they do
not impede the flow of water to the storm drains and shall be covered to avoid run-off during
rain.
24
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 4
15. The Contractor will be required to pay for any public off-street or on-street “time-limited” parking
spaces, within the University Avenue and California Avenue business districts or Stanford
University areas that will be rendered unusable to the public as a result of the permitted
operations. This includes spaces to maintain traffic lanes, for parking of construction vehicles
during work hours, for issuing parking permits to parked vehicles displaced from their private
parking spaces, etc. The proposed use of parking spaces must be included in the traffic control
plan submission.
16. All open trench and excavations must be backfilled and paved with temporary asphaltic concrete
or steel-plated at the end of each work day with non-skid plates. The Contractor shall place cold
cutback around the edges of non-skid steel plates and elsewhere as necessary to eliminate
vertical edges. For ADA compliance all cutback on sidewalks shall be placed so there will be a
12:1 slope to allow disabled access.
17. Spillage resulting from hauling operations along or across any public traveled way shall be
removed immediately by the Contractor at the Contractor’s expense.
18. Compliance with the City of Palo Alto Truck Route Regulations is required at all times.
19. Contractor shall obtain a Transportation permit from the Transportation Division for any vehicle
that exceeds weight or dimensions prescribed in California Vehicle Code.
20. Any work along El Camino will require a permit and approval from the State of California
Department of Transportation (Caltrans), and work along Oregon Expressway, Page Mill, and
Foothill Expressway requires a permit and approval from Santa Clara County Transportation
Agency.
21. The contractor shall use only Caltrans-approved traffic control devices. The Contractor shall
supply, place, and maintain all necessary traffic control devices in accordance with the State of
California “Manual of Traffic Controls for Construction and Maintenance of Work Zones”.
22. In general, Contractor shall maintain all vehicular, pedestrian, and bike movements. If possible,
the Contractor shall maintain one lane of traffic in each direction at all times on all streets. The
clear width of the lane shall be a minimum of 10 feet. When a bike lane is closed in conjunction
with a vehicle lane, the clear width of the lane shall be a minimum of 14 feet. No total closure of
any arterial or collector street, business district street, or alley will be permitted. City may allow
closure of local residential streets, but contractor shall always maintain local and emergency
access and provide a signed detour route around the closure.
23. Flashing arrow boards shall be used at all times when shifting traffic to the opposite side of the
street, shifting traffic at night, for work on arterial streets (Middlefield, Alma, Embarcadero,
University, Charleston, Arastradero, Sand Hill, and San Antonio), and as otherwise required in
the approved traffic control plan.
24. All warning signs and cones for night lane closures shall be illuminated or retroreflective.
Retroreflection of 28-inch cones shall be provided by a 6” white band and a 4” white band.
Flashing warning lights shall be used for all night lane closures.
25. Contractor shall use “Bike Lane Closed Ahead” and “Bike Lane Ends” signs when necessary to
close bike lanes. Detour signs shall be provided for any Class I bike path closure.
26. Work shall not restrict visibility of any traffic control device.
25
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 5
27. A minimum four feet (clear) sidewalk shall be maintained unless the work makes closure
unavoidable, in which case the sidewalk may be closed while working, subject to the approval of
the Project Manager. During sidewalk closures, R96 “No Pedestrian” signs shall be posted at
the site and R49M “Sidewalk Closed – Use Other Side” signs posted on both sides of the site at
the nearest corners. If the other side of the street is not available or practical for pedestrian use,
an alternate pedestrian facility shall be provided for the duration of the closure. The alternate
facility shall conform to construction requirements of the Uniform Building Code (UBC) and the
Americans with Disabilities Act (ADA). At intersections, work will be permitted at one corner at a
time, so pedestrian movements can be maintained through the intersection.
28. The construction hours for Utilities CIP project are generally 8 AM to 4:30 PM, Monday through
Friday, unless otherwise noted. Refer to City’s Traffic Control Manual and Requirements for
Traffic Control Plan Submission for further time restrictions in downtown areas, business
districts, on arterial streets, in bike lanes, and near schools.
29. All work within 1500 feet of the school or hospital shall be coordinated with the school or
hospital administration. No work will be permitted within 1500 feet of school grounds or along
school routes, as shown on adopted Walk and Roll Maps, until after 8:45 a.m. on school days
(see latest PAUSD School Year Calendar). Other special restrictions may be required at heavily
used school crossings or school commute routes beyond 1500 feet from the school grounds, as
deemed necessary for student safety by the Project Manager.
30. Work on arterial and collector streets will not be permitted between the hours of 7:00 and 9:00
AM and 4:00 and 6:00 PM. The restricted streets include: Alma St, Arastradero Rd, Arboretum
Dr, California Ave, Channing Ave, Colorado Ave, E Bayshore Rd, E Charleston Rd, E Meadow
Cir, E Meadow Dr, Embarcadero Rd, Fabian Wy, Louis Rd, Middlefield Rd, Palo Alto Ave (west
of Alma St), San Antonio Rd, Sand Hill Rd, University Ave, Hansen Wy, Hillview Dr, Park Blvd,
Stanford Ave, Quarry Rd, W Charleston Rd, Bayshore Rd W Meadow Dr, and Welch Rd. Any
exceptions to these must be approved by both the Public Works Department and Planning and
Community Environment Department – Transportation Division.
31. Projects affecting motor vehicle, pedestrian or bicycle traffic in business districts is generally
only permitted between the hours of 9:00 AM and 4:00 PM. Business Districts include the
following areas:
x University Ave District (Downtown):
bounded by Alma St, Webster Ave, Lytton Ave, and Forest Ave
x California Ave District:
bounded by El Camino Real, Caltrain corridor, Sherman Ave, and Cambridge Ave
32. No closure of any lane within 200’ of signalized intersection will be permitted between 7 A.M. to
9 A.M. and between 4 P.M. to 6 P.M. In addition, work will not be allowed at or within 200' of
signalized intersections between 11:30 A.M. and 1:00 P.M.
33. If work will impact transit stops or transit routes, contractor shall be required to contact Santa
Clara County Transit District, Samtrans and other affected transit companies to address
relocation of facilities or rerouting of buses prior to submitting traffic control plan. Traffic control
plan should indicate what actions are being taken with regard to transit services.
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SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 6
34. Any work within 150 feet of any signalized intersection shall be coordinated with the City of Palo
Alto Traffic Signal Supervisor at (650) 496-6991.
35. Traffic shall be fully restored outside the permitted work hours, unless approved Traffic Control
Plan modifies work time limitations. Violation of any of the above listed restrictions will lead to a
penalty charge to the Contractor at the rate of $200/hour.
36. Any work in vicinity of a signalized intersection within Caltrans R/W shall be coordinated with
Caltrans Signal Operation Division and performed in accordance with the conditions of and
encroachment permit.
37. Except in emergency situations, any traffic detour requires five (5) working days advanced
notice in order to insure proper advanced planning.
38. The contractor shall place barricades 50 feet on center at the gutter joints and provide one
working flasher for each barricade and shall insure that each flasher is maintained in working
condition while in use. The Contractor shall not remove the barricades in the street at any given
location until the asphalt concrete patching adjacent to the gutter and/or gutter overlay has been
done and the hazard to bicyclists and motorists no longer exists.
39. Flaggers shall be equipped with a hard hat, an orange vest, and a C28 “STOP/SLOW” paddle
on a 5-foot staff. Additional advance flaggers may be required when traffic queues develop.
Flagger stations for work at night shall be illuminated as noted in Section 5-04.6 of the Manual of
Traffic Control for Construction and Maintenance Zones.
40. The Contractor may be required, at Contractor’s own expense, to hire City of Palo Alto Police
Officers to direct traffic if the traffic signals at an intersection or crossing become inoperable due
to the Contractor’s work, traffic control setup does not conform to the approved traffic control
plan, or if the Project Manager determines that Police Officers are necessary to safely guide
traffic through the intersection.
1.03 SAFETY
All work shall be conducted in a safe manner and in strict accordance with the rules of the State Division
of Industrial Safety (Cal OSHA). The Contractor shall take all reasonable precautions necessary to
protect from personal injury all workers and other persons who may be in or about the construction area
and to prevent damage to both public and private property. Workers in the public right-of-way shall wear
orange safety vests and hard hats at all times.
The Contractor shall assume sole and complete responsibility for job site conditions during the course of
construction of this Project, including safety of all persons and property; that this requirement shall apply
continuously and not be limited to normal working hours; and that the Contractor shall defend, indemnify
and hold the City harmless from any and all liability, real or alleged, in connection with the performance
of work on this Project.
The Contractor shall notify the City in writing of all accidents arising out of work performed under this
Contract and shall submit to the Engineer a detailed report of each such accident within 24 hours of the
event.
The Contractor shall protect open excavations, trenches, manholes, and such during construction with
steel plating, fences, covers, and/or railings, together with adequate barricades with at least one working
flasher each, signs, lights, and other warning devices, sufficient to maintain safe pedestrian, bicycle and
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SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 7
vehicle traffic. The warning devices shall not be removed until the asphalt concrete patching adjacent to
the gutter and/or gutter overlay has been completed and the hazard no longer exists.
If, in the opinion of the Engineer, some portion of the work is being done in an unsafe manner, the
Engineer may order that portion of the work stopped until proper methods have been adopted by the
Contractor to make it safe.
The duty of the Engineer is to conduct construction review of the Contractor's performance and is not
intended to include review of the adequacy of the Contractor's safety measures on or near the
construction site. Nothing in this Section shall operate or be construed to impose any text or contractual
liability on the City or its employees for the Contractor's safety responsibilities.
The above requirements are a minimum and do not limit the Contractor's responsibility of doing all that
is practical and necessary to ensure the safety of workers, pedestrians, bicyclists and motorists.
1.04 SANITATION FACILITIES
Temporary Sanitation facilities, required for construction personnel, shall be provided by the Contractor.
Temporary Sanitation facilities shall be on a trailer and transported to-and-from the active jobsite daily.
The Contractor shall apply for an encroachment permit where a Temporary Sanitation facility remains
unhitched and left at the jobsite beyond the defined work hours. Contractor shall maintain sanitation
facilities on a weekly basis or more frequently if required. If there are any odor complaints, the
Contractor shall clean and move sanitation facilities to another location.
1.05 STORAGE OF EQUIPMENT AND MATERIALS
A. Contractor Off-Site Storage Area
The contractor is required to secure an offsite storage area suitable to store equipment, structures,
pipe and granular material. The cost associated with securing an off-site storage area must be
included in one or more of the contract bid items.
Furthermore, contractor access and work at the offsite storage area within Palo Alto City limits shall
meet County of Santa Clara and/or City of Palo Alto’s best management practices including but not
limited to: tarping new material piles; wetting down storage area to mitigate dust; tarping
spoils/offhaul material piles; and off hauling spoils daily. Unless in a commercially zoned area, work
hours for access to the storage area shall be limited to 8:00AM-5:00 PM Monday through Friday.
B. Policy for Storage of Equipment, Pipes, Structures and Granular Materials in the Public
Right-of-Way
All storage in the public right of way shall be performed in strict compliance with City of Palo Alto
Public Works Policy for storage of equipment, pipes, structures and granular materials in the public
right-of-way.
Contractor shall adhere to all of the City’s on-site storage policies. The City has the right to revoke
storage of materials and equipment within the City’s Right-of-Way for non-compliance with the City’s storage policies.
Within the City’s Right-of-Way, the Contractor is only permitted to store up to four (4) construction vehicles or equipment (excavators, backhoes, wheel loader, skid steer, etc.) beyond the work
hours defined for the project, regardless of crew size or location. Paving rollers will only be allowed to be stored within the City’s Right-of-Way every two weeks for a maximum duration of two days
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SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 8
and only when paving is scheduled.
Trench plates and backfill material that is planned to be used for the current week’s scheduled work may be stored within the Public Right-of-Way beyond the work hours defined for this project.
Contractor shall coordinate with the City’s inspector(s) to identify a suitable location to temporarily
store material and equipment.
All equipment and material temporarily stored at the construction site, within the Public Right-of-Way, shall be relocated to the active job sites and cannot remain at any given job site after the
work is completed. In addition, all granular material shall be removed at the end of each work week and before rainfall starts.
If a complaint from the public is received by the City regarding the Contractor’s equipment or materials, the contractor may be directed to relocate or remove all equipment and/or material from
the City’s Right-of-Way.
Prior to storage of any equipment or material, Contractor shall notify the City Inspector(s) of the
proposed equipment or material storage sites and request the City Inspector(s) to take pictures
and/or video of the storage sites. If Contractor fails to provide this notification, Contractor shall be
held liable for any damage sustained by the storage site and be responsible for site restoration to
preconstruction conditions as directed by the Inspector(s).
C. General Storage Requirements
It is the Contractor's responsibility to locate a site for the storage of equipment, materials, and office
facilities and to obtain and pay for all permits and fees necessary to make the site legal for storage.
The Contractor shall not store any equipment or material on private property zoned for residential
use. This includes commercial and industrial lots adjacent to residential property.
Any commercial or industrial property being considered as a storage site will require proper permits
from Planning & Development Services Department.
Equipment and materials, which are part of the Contract, shall be protected and stored in
accordance with the recommendations of the manufacturer. The Contractor shall assume the risk
of loss or theft of or damage to all equipment and materials delivered to or accepted by him or her
until such equipment and materials have been completely installed and accepted by the Engineer.
Storage in public right of way will not require an Encroachment Permit, but will require the prior
approval of the appropriate authority.
1. Additional Requirements
a. Equipment, pipe, structures, and granular materials shall be placed within one block of
the location where it is to be used, but no less than three blocks or 1000 feet from an
adjacent non-related project. Alternate locations may be determined by the appropriate
authority if construction and traffic conditions warrant.
b. Equipment, pipe, structure, and granular materials shall not block access to or visibility
of any fire hydrants, driveways, traffic signs, utilities, intersections, sidewalks, bike
lanes, crosswalks or drainage paths.
c. A minimum pavement width of 24 feet shall be maintained for traffic purposes.
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SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 9
d. No equipment, pipe, structures, or granular materials shall extend more than eight feet
into the street from the face of the curb and in no other case shall extend more than
one third of the roadway.
e. Two (2) type II barricades, with working flashers, shall be placed at each end of the
storage area.
f. One (1) type II barricade, with working flasher, shall be placed at 25-foot intervals along
the street side of the storage area.
g. Only the amount of pipe and structures that can be installed and back-filled in five (5)
consecutive days shall be stored in the public right-of-way.
h. Pipe or structure that can be easily lifted by hand and weighing less than 200 pounds
shall not be stored in the public right-of-way.
i. Steel deck plates shall not be stored in the public right-of-way.
j. Contractor shall hand deliver advance notice door hangers to businesses, residents, or
others, at locations where equipment, pipe, structures, and granular materials will be
stored, at least seven days in advance of the storage date. City will provide required
notices.
2. Trucks and Equipment
a. Equipment is defined as, but not limited to, backhoes, trenchers, loaders, rollers, self-
propelled pavers, and graders.
b. Only equipment in good mechanical condition shall be stored in the public right-of-way.
c. Any equipment that can not be repaired by the end of the day shall be removed
immediately from the public right-of-way.
d. Fluid leaks shall be repaired prior to the end of the day.
e. Spilled fluids shall be cleaned-up and disposed of in accordance with applicable
hazardous waste laws.
f. All equipment and materials shall be removed at the request of the Engineer for reasons
related to weather, job shutdown, safety or reasonable complaints and requests from
residents, and/or business owners.
g. Trucks and portable equipment, such as generators, compressors, and arrow boards,
shall be removed at the end of the day.
3. Granular Material
a. Granular material, such as backfill, bedding and cutback shall be placed against an
appropriate portable barrier, such as k-rail, to protect the curb and improvements
behind the curb.
b. The barrier shall be located a minimum of one foot in front of the face of the curb, so as
not to obstruct the drainage of water, unless otherwise directed by the Engineer.
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SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 10
c. No more than the amount of granular material that can be used in two (2) consecutive
days shall be stored at any time.
d. No granular material shall be stored within ten (10) feet of any catch basin or curb
return.
e. Granular material shall not be allowed to enter the storm drain or sanitary sewer
systems.
f. A tarp covering the granular material and sandbag berms placed around the granular
material shall be used as required by the Engineer during rainy periods.
g. The job site shall be swept clean at the end of the workday. An Athey Mobile Street
Sweeper Model AHL M9 or an approved equal shall be used.
1.06 CLEANUP
A. Daily
The Contractor shall not allow the job site to become littered with trash and waste material but
shall maintain the site in a neat, orderly, and dust free condition on a daily basis, or as required
by the Engineer, throughout the construction period. The Contractor shall conduct his or her
operations and schedule cleanup so as to cause the least possible obstruction and
inconvenience to vehicle, bicycle or pedestrian traffic, and adjacent property owners.
All work areas shall be kept in a dust-free state. A mobile street sweeper shall be used daily to
maintain a dust-free condition. At the end of each working day all work areas shall be swept
clean by an Athey Mobile Street Sweeper Model AHL M9 or an approved equal, subject to the
approval of the Supervisor of the Public Works Inspection Group.
All landscaped areas shall be left with a neatly graded surface, conforming to the adjacent
existing ground. All sidewalks should be manually swept to maintain a dust-free condition.
Spilled fluids shall be cleaned up and properly disposed of immediately, using an appropriate
absorbent material, by the Contractor at the Contractor's expense.
Spillage resulting from the Contractor's hauling operations along or across any public traveled
way shall be removed immediately by the Contractor at the Contractor's expense. All hazardous
materials shall be cleaned up per the Fire Department’s and Public Works Department’s policies,
and all applicable hazardous waste laws and regulations.
B. Final
Execute final cleaning prior to final inspection.
1. Clean all furnished equipment to insure proper operation; remove temporary labels, stains,
and foreign substances.
2. Clean site; sweep paved areas.
3. Remove waste, surplus materials, and rubbish from project sites to proper legal disposal
areas selected by Contractor so that the entire job site and all areas that were occupied by
Contractor during the project are restored to pre-job conditions.
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CITY OF PALO ALTO Section 1500 PAGE 11
4. Existing buildings, street furniture, equipment, piping, pipe covering, paving, sewer laterals,
sewers, trees, curb and gutter, sidewalks, landscaping, sprinkler systems, bridge abutments,
gas and water services, etc., and other public and private property damaged by the
Contractor during the course of his work shall be replaced and/or repaired either by the City
or the Contractor at the Contractor’s expense.
5. The Contractor shall completely remove all remaining USA markings and all other markings
associated with this project from pavement, sidewalk, curbs, driveways, etc.
1.07 SIGNAGE
At the beginning of each workday, the Contractor shall provide project signs for the ends of each
location/street where work is being performed. Signs shall include name of Contractor, Contractor
contact information, name of project, dates of work, and work hours (may vary depending on the
project location). It is the Contractor’s responsibility to move the signs as the project progresses. All
costs of project signs, and the associated labor costs to place and move the signs as the project
location changes, must be included in one or more of the Bid items. No additional compensation shall
be paid to the Contractor for project signs.
Sign Specifications:
Size: 3’ X 5’
Color: black letters on white reflective background w/ black border.
Letters: black, 1" min height, 1/4" thick Arial font, spacing approx. as shown below.
Dates or work and work hours shall reflect the correct information at each project location.
Each sign shall be attached to a barricade which can be moved from one construction site to the
next. An information box (see attached .gif file) shall also be attached next to the sign. The City will
provide the information letters. The Contractor shall provide the box.
Sample Sign:
Project Name
Month Year – Month Year
Monday- Friday 8 am to 5 pm
Contractor’s Name
Contractor’s Local Phone Number
Project Website: https://www.cityofpaloalto.org/Departments/Utilities/Utilities-Services-Safety/Utilities-Projects
END OF SECTION
City of Palo Alto
Utilities Department
(650) 566-4501
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EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 1
SECTION 2200
EXCAVATION, BACKFILL, AND RESTORATION
PART 1 - GENERAL
1.1 DESCRIPTION
Excavation, backfill, and restoration shall conform to the City of Palo Alto Department of Public
Works Standard Drawings and Specifications, and as specified on the project plans. Excavation
and backfill shall conform to the safety requirements of the Contract and the approved traffic control
plans.
1.2 WATER AND WASTEWATER MAINS OR SERVICES INSTALLED BY DEVELOPMENT
SERVICES APPLICANTS
For applicant-installed water and wastewater mains or services (gas shall only be installed by Palo
Alto Utilities crews or City Contractor), the applicant shall submit the following to the WGW
engineering section of the Utilities Department:
A. Electronic copy of the installation of water and wastewater utilities off-site improvement plans
in accordance with the Utilities Department design criteria. All utility work within the public right-
of-way, or the public portion of the utilities, shall be clearly shown on the plans that are
prepared, signed and stamped by a registered civil engineer.
B. A complete schedule of work.
C. Method of construction including abandonment details.
D. The manufacturer's literature on the materials to be used for approval by the Utilities
Engineering Department.
E. PE pipe fusion certification by City-authorized testing company or personnel.
The applicant's contractor will not be allowed to begin work until the improvement plan and other
submittals have been approved by the Water, Gas and Wastewater Engineering Department.
WGW inspections shall be scheduled at least five (5) days in advance.
After the work is completed, but prior to sign off, the applicant shall provide record drawings (as-
builts) of the installation of water and wastewater utilities to be owned and maintained by the City.
PART 2 - BACKFILL AND RESTORATION MATERIALS
Contractor shall prepare submittals for sand, 1/2" crushed rock, 3/4" aggregate base, and controller density
fill (CDF), for Engineer's approval. The Contractor shall also prepare all submittals required by Public Works
Department per Public Works Standard Drawing and Specifications.
2.1 BACKFILL
All backfill materials shall comply with the drawings and be in accordance with the latest edition of
the California Department of Transportation, Standard Specifications. Excavated material shall not
be used for pipe bedding or trench backfill.
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EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 2
2.2 SAND
Sand shall conform with Section 19-3.02F(2) of the latest edition of the Caltrans State Standard
Specifications and shall be imported clean natural sand, free from clay, salt, sea shells, or organic
material, suitable for the purpose intended and shall conform to the following gradation:
No. 4 sieve…………… 90% - 100%
No. 200 sieve………… 0% - 5%
Dredged sand from San Francisco Bay is not acceptable.
2.3 Class 3 Permeable Material (1/2" CRUSHED ROCK)
1/2" crushed rock will be designated by nominal size and shall conform to the following gradation
when tested in accordance with sections 6 and 68-2.02F(4) of the latest edition of the Caltrans
State Standard Specifications
Class 3 permeable base:
Passing a 1-1/2” sieve………….............. 100%
Passing a 1” sieve………………………. 88% - 100%
Passing a 3/4” sieve…………………….. 52% - 85%
Passing a 3/8" sieve............................... 15% - 38%
Passing a No. 4 sieve............................ 0% - 16%
Passing a No. 8 sieve............................ 0% - 6%
This material shall contain at least 75% of the particles having one or more fractured faces. Not
over 25% shall be particles showing no such faces.
Crushed rock shall meet the test grading requirements of ASTM C 131 test grading B.
2.4 Class 2 Aggregate Base (3/4”)
Class 2 (3/4") will be designated by nominal size, shall conform to the following gradation, and shall
meet the requirements of Sections 6 and 26-1.02B of the latest edition of the Caltrans State
Standard Specifications:
Passing a 1” sieve………………………...100%
Passing a 3/4" sieve............................ 87% - 100%
Passing a No. 4 sieve.......................... 30% - 65%
Passing a No. 30 sieve.......................... 5% - 35%
Passing a No. 200 sieve...................... 0% - 12%
2.5 CONTROLLED DENSITY FILL (CDF)
A. Materials:
1. Cement: ASTM C150, Type II or V, 1-1/2 to 2 sack mix.
2. Aggregate: Mixture of clean sand and pea gravel, 3/8 inch maximum size.
3. Fly Ash: ASTM C-618 Class F.
4. Water: Potable water or water of similar quality which is free of deleterious impurities.
5. May use suitable admixture(s).
B. Mix Design and Performance:
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EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 3
1. CDF shall be non-segregating, flowable, self-consolidating, low-shrink material that flows
into place without leaving voids and cures into a stiff non-plastic material.
2. Compressive strength: 28 day strength between 50 psi and 200 psi.
3. CDF shall be supplied by a concrete manufacturing plant.
4. Place CDF so as not to float the pipes.
C. Submittals:
1. Mix design.
2. Samples of the material to be used.
3. Results of laboratory trial mix compressive strength testing using 6” diameter by 12” test
cylinders with cylinder breaks at 7 and 28 days (28 day test shall be average of 2 or more
cylinder breaks).
PART 3 - EXECUTION
3.1 EXISTING UTILITIES AND USA
The Contractor shall comply with IFB Part 5 General Conditions 3.28 and additional requirements
in this section for Underground Service Alert (USA). For Utilities projects, it is the Contractor's
responsibility to notify Underground Service Alert (USA at 811) a minimum of ten (10) Working
Days in advance of starting excavation. The Contractor shall delineate the areas of work with white
paint. Contractor shall only request utility markings at those locations where underground work will
occur during the following month.
Prior to excavation, the Contractor shall verify that all utilities shown in the contract documents or
observed in the field from existing aboveground utility features, have been USA-marked. Notify
USA and schedule a meet and mark at least three (3) working days prior to excavation, if any utility
has not been marked, has been marked differently than what’s shown in the project plans, or the
marking appears to be inaccurate judging by the existing aboveground features for the utility. If the
Contractor is unable to locate identified underground utilities while excavating, based on USA
marks or information provided in the contract documents, the Contractor will contact the responsible
utility owner to locate those facilities.
Where underground utility mains such as water, gas, wastewater, electric, telephone, or cable
television are shown on the project plans, the Contractor shall assume that every property parcel
adjacent to or on the same street as the underground utility mains has an underground service for
each type of utility present. In addition, the Contractor shall assume that each property parcel with
either an above ground or at grade facility, such as a water meter box, gas meter, or sanitary sewer
clean out, has an underground service for the respective utility. If a service is not shown on the
project plans for any parcel, not marked, or marked in the incorrect location according to the project
plans, the Contractor shall bring it to the attention of the WGW Utilities Inspector at least three
working days prior to digging to allow time to resolve the conflict.
If USA re-marking is required due to any reasons, the Contractor shall anticipate up to two (2)
working days turn-around time. No additional compensation for standby or waiting time shall be
paid to the Contractor, subject to the limitations set forth in Public Contract Code section 7102, if
applicable.
The Contractor shall completely remove all USA markings and all other markings associated with
this project from pavement, sidewalk, curbs, driveways, etc. The method used for removal of the
markings shall be approved by the City. The cost to remove the USA markings shall be included in
one or more Bid items and no extra compensation shall be paid to the Contractor.
Methods of protection of existing utilities shall be approved by the Engineer prior to the start of
crossing the existing utilities. All utilities crossing or lying along the trench shall be supported. The
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EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 4
work of bracing and the care of all encountered utilities below grade shall be considered a part of
excavation and backfill.
If it is necessary to relocate or temporarily remove and replace existing underground utilities, the
Contractor shall first obtain permission from the utility concerned and comply with its requirements
in performing the necessary work. Gas and water line relocations shall be performed by the City.
All costs incurred shall be paid by the Contractor. Property owners shall be notified at least 24
hours before the planned disruption of any utility service.
Shut down of City WGW Utilities shall be performed by City of Palo Alto Utilities WGW Operations
Division. The Contractor shall not disconnect or shutdown any part of the existing City of Palo Alto
WGW Utilities System except by expressed written permission of the Engineer. Notify the Engineer
five (5) working days in advance of required shutdowns and submit a schedule of the estimated
shutdown time to obtain said permission.
The contractor shall pothole all crossing and nearby parallel utilities both public and private within
the work area. The Contractor shall proceed with caution during the trenching operation to avoid
damage to the existing underground utilities. Caution must also be exercised when installing new
pipe by directional boring methods. All existing utilities crossing the proposed bore path must be
prospected prior to establishing the pilot bore path. Locator devices, careful probing, vacuum, and
hand methods of excavation shall be employed to determine the exact horizontal or vertical
alignment of underground facilities. All exposed gas lines and electric facilities shall be inspected
for damage by the WGW Utilities and Electric Utilities Inspectors prior to backfill. The Contractor
shall immediately notify the Engineer if any Underground Facility is disturbed or damaged.
Repairs to existing City wastewater utilities shall be performed by the Contractor, unless otherwise
directed by the Engineer. City forces shall repair, relocate, or replace all other City utilities. The
Contractor shall accommodate City forces in his or her operations. The Contractor shall pay for
the full cost to repair the existing utility mains or services, public or private, damaged by
his or her operations and any other damages resulting from the damaged utilities when the
damage is due to the Contractor’s failure to exercise reasonable care with utilities that are
indicated in the plans and specifications with reasonable accuracy.
The Contractor shall take extreme caution when excavating adjacent to electrical conduits/wires,
fiber optic conduits/wires, and traffic signal loops/conduits/wires. The Contractor is expected to
carefully crack the concrete and hand-dig when excavating around traffic signal conduits, as they
may be shallow and often embedded in concrete and/or asphalt road surface. When a conduit cut
or dig-in occurs, the Contractor shall postpone excavating around the conduits to avoid further
damage until Electric Operations assesses their condition and repairs are performed. Any damage
to electrical conduits, fiber optic conduits, or traffic signal loops and conduits shall be repaired by
the contractor at no cost to the City. Any damage to electrical substructure/cable/wires, gas lines,
or water mains will be repaired by the city and the cost will be paid by the Contractors. An electrical
Inspector shall be present while the contractor repairs electrical, fiber optic, or traffic signal
conduits. The Contractor shall contact Electric Operations Dispatch at 650-496-6914 to schedule
electrical inspection.
The cost of repairs performed by City crews will be billed to the Contractor by the WGW or Electric
Operations Division and shall be paid independently by the Contractor to the City's WGW or Electric
Operations Division. Payment must be made when submitting monthly progress payment request.
Final project approval or payment will not be made until these bills have been paid.
Wrapping on any exposed steel gas lines shall be inspected by the City prior to backfill. Repairs of
customer-owned sprinkler systems shall be made by the Contractor at their own expense.
Contractor shall repair customer-owned portions of water and gas services damaged by the
Contractor, at the Contractor’s sole expense. The repair work must be performed by a licensed
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EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 5
plumber in accordance with the requirements of UPC and City of Palo Alto Building Inspection. The
Contractor will be responsible for coordinating access to private property with the owners.
3.2 POTHOLING
The contractor shall locate and pothole all existing crossing utilities and parallel utilities within 5
feet of the designed pipe alignment. The Contractor shall pothole and confirm there is sufficient
vertical or horizontal separation between the existing utilities and the designed pipe alignment at
least three (3) working days prior to performing any construction activities for the proposed pipe.
x If the existing crossing or parallel utility is at a higher elevation than the designed pipe elevation,
the Contractor shall daylight and expose the bottom of the existing pipe/conduit/duct/duct bank.
x If the existing crossing or parallel utility is at a lower elevation than the designed pipe elevation,
the Contractor shall expose the top of the existing utility.
x For parallel utilities, the Contractor shall pothole every 100 feet until the utility is beyond the 5-
foot parallel zone.
x The Contractor shall allow the Inspector or Engineer to have clear visual of the existing utility
in each pothole as the drilling or bursting head passes through the existing utility. This is to
ensure that the existing utility/structure is not damaged by the drilling/bursting operation.
x For third party utilities such as PG&E’s high pressure gas mains, the Contractor shall comply
with the utility owner’s potholing requirements.
The Contractor is required to fully examine and inspect the project site and have full knowledge of
the physical conditions of the project area prior to submitting the bid. For public or private utilities
that are not shown on the project drawings but can be anticipated from the presence of other visible
features or facilities, the Contractor should include the cost under one or more bid items to locate
and pothole these utilities in the project area. The Contractor shall pothole as required to determine
the exact locations and elevations of existing utilities at least three (3) working days prior to any
construction activities for the proposed pipe at the subject location to allow sufficient time to resolve
potential issues. Using the USA markings as a guide and/or in agreed-upon locations with the City
Inspector, the Contractor shall make at least two (2) potholes to locate each utility, public or private,
before the City will consider additional compensation for extra work or delays. The Contractor shall
anticipate a 2-day turn-around time for re-marking of public or private utilities. See Part 3.01
(Existing Utilities and USA) of this Specification for additional information on USA marking
requirements.
For trenchless construction, all potholed existing crossing and parallel utilities shall remain exposed
and visible throughout the boring or pipe-bursting operation and shall be inspected by the WGW
Utilities Inspector and/or Public Works Inspector during the trenchless operation or prior to backfill.
It is the Contractor’s responsibility to investigate any unknown or conflicting utilities and to contact
the public or private utility agency or owner to resolve the conflicts identified during potholing
activities. The City is not responsible for any delays or additional costs associated with unmarked
third-party utilities.
3.3 Gas Main Replacement Projects
Pre-Installation CCTV Inspection
Prior to installing new gas pipelines by trenchless methods, the Contractor is required to use a
CCTV camera through any sewer main meeting the criteria listed below, to accurately document
and mark all lateral connection points and identify the alignment of all sewer laterals on public and
private properties.
x Sewer mains with any connecting sewer lateral that will be crossed by the proposed gas
pipelines.
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x Sewer mains with any connecting sewer lateral that is serving the same property as the
proposed gas pipeline or stub.
x Sewer mains with any connecting sewer lateral that is on an adjacent property, but within 10
feet of a proposed gas pipeline.
Contractor shall submit the CCTV logs and video footage for each sewer main with the monthly
progress payment request.
If the Contractor’s CCTV inspection of the sewer pipelines show the pipeline is blocked by roots or
debris, Contractor shall clean the sewer pipeline by flushing until CCTV inspection can be
completed. See Section 2739 “Cleaning and Video Inspection of Sewer Pipe” for requirements. If
there are any obstructions in the sewer main that deemed by the Engineer as unable to be
addressed by cleaning, Contractor shall provide City Operations crew 10 business day notice to
schedule time to assist Contractor with removal of obstructions.
Post-Installation CCTV Inspection
On natural gas main and service replacement projects using trenchless installation methods, post-
installation cross-bore CCTV inspection must be performed on public and private sewer pipelines
when:
x The newly installed gas pipelines cross sewer pipelines.
x The sewer pipelines are serving the same property as the newly installed gas pipeline or stub.
x The sewer pipelines, on an adjacent property, are within 10 feet of a newly installed gas
pipeline.
See Section 2741 “Legacy Cross Bore Inspections Guidelines” and Section 2739 “Cleaning and
Video Inspection of Sewer Pipe” for requirements.
Once installation of the new gas pipelines has been completed using trenchless installation
methods, the Contractor shall perform CCTV inspections to positively verify and document that no
sewer pipelines were damaged during installation. City and private sewer clean-outs may not
always be accessible or present; therefore, the Contractor shall use lateral-launch and push
camera equipment to inspect all sewer pipelines, including sewer pipelines that were not USA
marked or shown on the project plans. All sewer pipelines must be CCTV-inspected and cleared
of a cross-bore, per Specification Section 2741, prior to the City performing gas tie-ins. The
Contractor is also required to perform CCTV inspection of sewer pipelines at all properties where
reconnection is specified, regardless of length of newly installed gas service.
The video inspection must include entire length of the sewer lateral from the wastewater main to
the foundation of the structure or extend three (3) feet beyond the furthest gas riser, whichever is
furthest. Inspection must include sewer lateral branches and cleanout risers. Inspection length will
be determined by the City Inspector assigned to the project. For each sewer pipeline inspection,
the Contractor shall make at least two attempts using the push camera and at least two attempts
using the lateral-launch camera. If using push camera or lateral launch equipment is not successful
following the repeated attempts, the Engineer may request the Contractor to pothole to clear the
sewer lateral from a cross-bore.
If the Contractor’s CCTV inspection of the sewer pipelines show the pipeline is blocked by roots or
debris, Contractor shall clean the sewer pipeline by flushing until CCTV inspection can be
completed. In the event a portion of the sewer pipeline is not cleared and all efforts to CCTV inspect
the sewer pipeline have been exhausted:
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x If the sewer pipeline and newly installed gas pipeline crosses, the Contractor will be directed
to excavate the crossing and have the City Inspector visually verify the separation between the
pipelines.
x If the sewer pipeline and newly installed gas pipeline do not cross, a proximity clearance may
be determined by the City Inspector assigned to the project. If a proximity clearance cannot
be determined, Contractor may be instructed to excavate and expose the entire length of the
gas pipeline for visual inspection.
If the Contractor is unable to find an existing City or private sewer clean-out and inspection efforts
have been exhausted, the City may direct the Contractor to expose the sewer lateral and install a
sewer cleanout per City Utility Standard Details WWD-02A and WWD-02B to facilitate video
inspection. The newly installed sewer cleanout must be inspected and approved by the City
Inspector. The Contractor will be compensated for this Work based on the applicable unit pricing.
If the sewer pipeline is blocked by existing damage or protruding taps, Contractor must provide an
image and location of each section for City Operations to investigate. In the event City Operations
is unable to address the sewer pipeline repair, Contractor may be directed to make the repair on
the sewer pipeline to facilitate the video inspection. Contractor shall receive approval from the City
prior to attempting to repair, clean or cut roots from the sewer pipelines. The Contractor will be
compensated for this Work based on the applicable unit pricing.
3.4 SAWCUTTING, DEMOLITION, AND REMOVAL FOR UTILITIES CONTRACTS
Trenching shall include the removal of all materials or obstructions of any nature, including asphalt
and concrete pavement. Areas in which sawcutting is performed shall be wet vacuum cleaned
to remove the cutting residual, inclusive of the sawcutting fluid. Sawcut slurry shall not be
permitted to enter storm drains. Areas in which sawcutting is performed shall be cleaned to
remove the cutting residual, inclusive of the sawcutting fluid, at the end of each workday or more
often as required by the Engineer.
Existing street sections shall be removed in such a manner so as not to destroy or damage the
structural integrity of the adjacent street section. Trench cutting shall be accomplished by using a
pavement saw, cutting through the full pavement thickness of the pavement section. No equipment
mounted pavement breakers shall be used. The top portion of the trench (i.e. the pavement
thickness) shall be twelve inches wider than the portion extending to the bottom. Lines shall be
marked along each side of the trench 6" beyond the edge of the trench and the pavement cut along
these lines. To achieve the "T" section required by the City of Palo Alto Public Works Standard
Drawings and Specifications "Typical Trench Sections" detail, generally four (4) parallel sawcuts
are necessary for any given trench. Removal of concrete sidewalks, driveways, curbs, and gutters
shall be to existing joints or to sawcuts made at existing score marks. Tunneling under street,
sidewalk, curb and gutter is not permitted except with directional or percussion bore devices and
as noted on the construction plans.
All pavement broken out of the trench will be removed by jackhammer, ripper teeth or backhoe. No
equipment mounted pavement breakers will be allowed due to the minimal cover over some
existing utilities. Valve boxes over abandoned utility main valves shall be removed from the street
sections, the risers filled with jetted sand, and the street section restored to match the existing
section.
Where the trench is to be located in a Portland cement concrete or asphaltic-concrete paved street,
lines shall be marked along each side of the trench and the pavement cut along these lines with a
concrete saw to the full thickness of the concrete. Only concrete saws for PCC-based pavement
shall be used to remove PCC pavement.
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It is the Contractor’s responsibility to locate a suitable disposal or recycling site for all material
removed from the trench. Asphalt concrete and Portland cement concrete must be disposed of at
an inert solids recycling facility, approved by the Engineer. Documentation of each load recycled is
required for payment.
3.5 SUBSURFACE CONDITIONS
Please refer to Invitation for Bid (IFB) Package Part 2 – Instructions to Bidders Section 18.0
(Subsurface Conditions) for information for Bidders regarding subsurface conditions.
3.6 EXCAVATION
It is the Contractor’s responsibility to fully examine and inspect the project site and documents
pertaining to the physical conditions of the project area, prior to submitting the bid, as further
specified in Instructions to Bidders Section 6.0 (Pre-Bid Investigation). The Contractor shall include
all necessary cost in one or more bid items to perform excavation and complete the work
successfully. It is the Contractor’s responsibility, prior to construction, to contact all outside
agencies or owners if the Contractor becomes aware of any actual or potential discrepancies
between existing field conditions and conditions shown on the project plans. Some utilities may be
identified from the presence of visible facilities, such as building, meters, junction boxes, manholes,
etc. Private irrigation pipes are typically not marked or shown on project plans. The Contractor
shall anticipate sprinkler/irrigation pipes to be encountered on private properties and near
landscaped median/island/planting strip, The Contractor is responsible to repair in kind if damaged
by the Contractor during the construction project.
The Contractor is required to exercise reasonable care when working around any existing utilities
at no additional cost to the City. If conflicts are found during construction activities, Contractor shall
also contact the responsible agencies or owners to locate their utilities or resolve the issues. The
City is not responsible for any delays or additional costs associated with third party utilities.
A. Trench Excavation (Ref. the City of Palo Alto Public Works Standard Drawings and
Specifications). The bottom of the trench shall be a minimum of 8 inches wider than the outer
diameter of the pipe. The depth of trench shall be at least the minimum depth of cover (30" for
gas main and 36" for 8” water main) plus 4" for pipe bedding plus the outer diameter of the
pipe. The Contractor shall support all existing utilities within the excavation or trench as
required to avoid damage to the existing utilities. A plan for supporting the existing utilities shall
be submitted for approval by the Engineer. The Contractor may not start work prior to approval
of the utility support plan.
For Utilities contracts, the cumulative paved surface area opened at any given time due to
potholing and/or excavations shall not exceed 500 linear feet. Potholes shall be classified as
open until final pavement resurfacing has been completed.
For CIP projects no more than one crew installing mains or services/laterals, unless approved
by the Engineer. Other work such as alignment layout, saw-cutting, potholing, trench plate
grinding, excavating, backfilling/restoration, cleaning, or GPS surveying can be performed
simultaneously.
For Utilities contracts, no excavation shall be left open during nonworking hours. All open
trenches and excavations shall be steel plated with non-skid type steel plates (nominal
Coefficient of Friction shall equal 0.35 as determined by California Test Method 342) or
backfilled and paved with temporary asphalt concrete (cutback) at the end of each workday.
Steel plates shall be shimmed with wooden wedges to prevent rocking and 2” of cutback shall
be used at the edges to provide a smooth transition from the pavement surface to the top of
the plates (one-foot wide minimum ramp with 24:1 slope). Steel plates subject to turning
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vehicles or vehicle acceleration and de-acceleration shall be welded together and/or anchored
to prevent movement. Additionally, steel plates shall not have any protrusions above the top
surface of the plate.
Plates shall be checked for proper placement at the end of each work day and
adjusted/leveled/shimmed as required. Steel plating shall be avoided in designated bicycle
lanes by backfilling and in installing temporary pavement at the end of each day. Plating
installed along bike boulevards, arterial roadways, or along roads with a posted speed limit of
35 MPH or greater shall be set flush with the surrounding asphalt concrete surface. Plating
installed in Class II bike lanes or bike boulevards shall be skid resistant and have a reflective
thermoplastic coating for additional safety and shall be set flush with the surrounding asphalt
concrete surface. Additional warning signage shall be posted on Type II flashing barricades All
temporary steel plates shall be removed within 14 calendar days after placement. Refer to the
City of Palo Alto Public Works Standard Drawings and Specifications for additional
requirements.
B. Handling of Pipes and Materials into the Trench. All fittings, valves, hydrant buries, manholes
and pipe lengths shall be carefully lowered into the trench by means of suitable tools and
equipment, in such a manner as to prevent damage to materials. Under no circumstances
shall utility main materials be dropped or dumped onto the work area or into the trench.
Pipe support stands shall be utilized to support pipe during fusion joining, directional boring pull
in, lining sewer mains, and while lowering of the pipe into the trench. Pipe support stands shall
not be spaced greater than 15' for directional boring pull in and lining sewer mains.
Throughout the duration of the job, the Contractor shall have a crew available to promptly backfill
and repair paving at trench and manhole locations where settlement or cave-ins have occurred.
The Contractor shall make periodic inspections of the trench at least once a week as well as
immediately after rain to repair any defect at once.
Sufficient pumping equipment shall be provided to maintain the bottom of the trench dry during
placement of the pipe bedding and other backfill material. The pump discharge water shall be
pumped into sewer or as otherwise directed by the Engineer. The pump discharge water shall not
be routed to natural drainage channels or storm sewers (Refer to Public Works Department Storm
Water Pollution Prevention policy).
All crossing pipelines shall be protected from damage during excavation by using hand tools or
Hydro-Vac to expose them. All exposed gas lines shall be inspected for wrapping damage by the
WGW Utilities Inspector prior to backfill. It is the Contractor’s responsibility to inform the WGW
Utilities Inspector when gas lines are exposed to facilitate an inspection.
Contractor is responsible for disposal of all excavated soils associated with the project during
construction. It is the Contractor’s responsibility to characterize all excavated soils for disposal by
sampling and testing it in accordance with landfill operation requirements. All samples shall be
taken in the presence of the City Inspector. The City will not pay for disposal of excavated soils that
were not sampled and approved by City Inspector prior to disposal. Once testing has been
completed, it is the Contractor’s responsibility to identify suitable landfill facility, and to transport
and dispose the excavated soils.
3.7 HIGH PRESSURE GAS AND HIGH VOLTAGE ELECTRIC
Extreme caution shall be used when working around PG&E high pressure gas mains and CPA high
voltage electric duct bank.
PG&E’s transmission pipelines can be reviewed in PG&E’s website
https://www.pge.com/en_US/safety/how-the-system-works/natural-gas-system-overview/gas-
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transmission-pipeline/gas-transmission-pipelines.page. When potholing or working within 10 feet
of PG&E mains, the Contractor shall contact PG&E twenty (20) business days prior to start of work
to coordinate and schedule standby inspection. Hand digging is required within 2 feet (tolerance
zone) on either side, of the outermost edge, of the PG&E mains. The Contractor shall include the
cost in one or more bid items and adequate lead time to comply with PG&E requirements such as
obtaining applicable permits, scheduling for inspection, locating, hand-excavation, restoration, etc.
When parallel boring or trenching is performed outside of the tolerance zone but within 5 feet of the
outermost edge of the PG&E facility, then pothole the edge of the PG&E facility, at 50 feet intervals,
on the same side of the bore or trench. The Contractor shall contact PG&E to confirm the latest
requirements.
When potholing or working within 10 feet of CPA electric duct bank(s) containing energized 60kV
cables, the Contractor shall notify Utilities Electric Operations at (650) 496-6914 at least five (5)
working days in advance of construction activities to schedule standby inspection. Hand digging is
required within 2 feet on either side of 60kV duct bank. The Contractor shall include the cost in
one or more bid items to comply with all Electric Utility requirements, including but not limited to:
observing the path of the bore-head, supporting thermal sand surrounding 60kV duct bank to
preserve as much of it as possible, hand-excavation, backfilling around 60kV conduits with new
thermal select backfill, restoration, etc.
3.8 ALIGNMENT AND GRADE CONTROL
The grade and alignment of new pipe shall be maintained by use of laser survey equipment. The
proposed equipment shall be submitted for approval prior to commencing the work. The Engineer,
at any time during the course of the work, may require alterations of the grade control method to
conform to the required conditions of the work.
3.9 SHORING FOR UTILITIES CONTRACTS
Pursuant to Section 6705 of the California Labor Code, for any contract over $25,000 involving a
trench or trenches five feet or more in depth, the Contractor shall submit a detailed plan showing
design of bracing, sloping or other provisions to be made for worker protection from the hazards of
caving ground. Such plan shall be submitted for acceptance at least five (5) days before the
Contractor intends to begin work on the trenches or shoring pits. If such plan varies from the shoring
system standards established by the Construction Safety Orders, the plan shall be prepared and
signed by a registered civil or structural engineer. Said plan shall be accepted by the Engineer prior
to any excavation.
When shoring is required at locations other than those specified in the bid items, the Contractor
shall, at no additional expense to the City, furnish, put in place, and maintain such sheeting and
bracing as may be required to support the sides of all excavations (whether above or below pipe
grade) and to prevent any movement which could in any way diminish the required trench section,
or otherwise damage or delay the work.
The Contractor shall support all existing utilities within the excavation or trench as required to avoid
damage to the existing utilities. Nothing herein shall be deemed to allow the use of a shoring,
sloping or protective system less effective than that required by the Construction Safety Orders of
the Cal. OSHA.
3.10 GROUNDWATER FLOW CONTROL
It shall be presumed that the presence of groundwater will require dewatering operations.
Contractor shall furnish, install, maintain, and operate all necessary pumping and other equipment
for dewatering all excavations, including well-points or wells containing submersible pumps. At all
times, the Contractor shall have on the project sufficient pumping equipment for immediate use,
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including standby pumps for use in case other pumps become inoperable.
Dewatering devices must be adequately filtered to prevent the removal of fines from the soil.
Provide discharge sampling locations for each pump and sample and test groundwater pumped
from dewatering devices daily during the first week and weekly thereafter. The results shall be
transmitted to the Engineer upon receipt of the lab reports. If soil fines are being pumped, revise
dewatering operations to prevent the removal of fines from the soil.
The Contractor shall be responsible for any damage to the underground utilities, roadwork, and/or
adjacent structures caused by the Contractor's negligence or willful misconduct, including any
failure of any part of the Contractor's protective works. After temporary protective works are no
longer required for dewatering purposes, they shall be removed by the Contractor.
If pumping is required on a 24-hour basis, engines shall be equipped in a manner to keep noise to
a minimum. Noise level shall conform to the requirements of the City's noise ordinance as stated
in the City of Palo Alto Municipal Code.
Prevent disposal of sediments from the soils to adjacent lands or waterways by employing whatever
methods are necessary, including settling basins. See latest project drawings and the City’s Public
Works Standards for additional requirements for groundwater treatment and disposal.
3.11 BACKFILL
A. Pipe Bedding
All excavated material shall be removed from the site. It is the Contractor's responsibility to
locate a suitable disposal site for all material removed from the trench. Asphalt concrete and
Portland cement concrete must be disposed of at an inert solids recycling facility, approved by
the Engineer. Documentation of each load recycled is required for payment. No shoring or
bracing shall remain in the trench after backfilling. No wedging or support of the pipe with wood
or any other type of material other than the pipe bedding material shall be permitted.
1. Soil Stabilization: Pipe bedding shall not be placed on unsuitable material. Any unsuitable
material encountered at the base of a fully excavated trench for the pipes or below the
grades shown for manhole excavation shall be removed as directed by the City Inspector.
The unsuitable material shall be replaced with subgrade stabilization material (Class 3
Permeable Material)) wrapped in geotextile fabric. The Contractor shall remove such
unsuitable material to a minimum depth of 12 inches below the bedding to a maximum of
24 inches below the bedding. Subgrade stabilization material shall be compacted per
requirements of Section 26-1.02B of the latest edition of the Caltrans Standard
Specifications to the satisfaction of the City Inspector. Geotextile fabric shall be Mirafi 600x
or equal. Overlap the seam running along the trench 12 inches minimum; overlap the seam
perpendicular to the trench 24 inches minimum.
Trench bed shall be smooth, uniform, and free of debris, sharp rocks, etc. before adding
the pipe bedding.
2. Pipe Bedding For Wastewater Plastic Pipe Construction: The bedding material shall be
washed, ½" crushed rock from 4" to 6" below the pipe to the spring line of the pipe and
compacted per requirements of Section 68-2.02F(4) of the latest edition of the Caltrans
Standard Specifications.
3. Pipe Bedding For Water and Gas Construction: The bedding material shall be sand
bedding 4" to 6" deep below the pipe compacted to a density of at least 90% of the
maximum density as determined by the California Test Method 216.
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After compaction, bell holes (if required) shall be cut in the material so that the pipe, when
laid, will have a uniform bearing under the full length of the barrel. The depth of compacted
select material shall be at a minimum of four (4) inches under the barrel, bell or couplings
of the pipe, and maximum of six (6) inches.
After the pipe has been properly laid in the trench, select material shall be placed on both
sides of the pipe and forced under the haunches of the pipe.
B. Initial and Subsequent Pipe Backfill
Initial backfill shall be placed uniformly on both sides of the pipe and in such a manner as to
avoid damage or movement to the placed pipe. Initial backfill shall be placed to a compacted
depth of 12 inches above the top of the pipe and compacted to 90% of maximum density per
ASTM D-1557. When sand is selected the Contractor may elect to “jet” and provide a location
where excess water can be collected at the low points and removed by pumping. Jetting and
vibration shall be at intervals not to exceed six (6) feet, in accordance with Public Works
Standard Drawing (401).
Subsequent backfill shall be placed in 8 inch lifts or less compacted to 90% of maximum density
per ASTM D-1557, with the final twenty four (24) inches mechanically compacted to 95% of
maximum density per ASTM D-1557.
C. Controlled Density Backfill (CDF)
CDF Backfill shall only be used as approved by the Engineer. A twelve (12) inch sand layer
shall be installed above the gas or water pipe before installation of CDF.
3.12 COMPACTION TESTING FOR UTILITIES CONTRACTS
Compaction testing will be performed by the City's contract soils laboratory under the general
direction of either the WGW Inspector or the Public Works Inspector. The Contractor shall
cooperate, by adjustment of his operation, in order to permit soils compaction testing on all backfill
materials. The City will pay for the initial compaction test; all subsequent compaction tests required
will be at the Contractor's expense.
One (1) full day advance notice will be required for any soil compaction test request. The City
Inspector will schedule the compaction testing according to the date and time provided by the
Contractor. If the Contractor is unprepared at the scheduled time, the Contractor shall pay for
delaying the soil compaction testing.
All other testing required by the Contract shall be provided at the expense of the Contractor.
3.13 PLAN MODIFICATIONS
Field conditions may necessitate minor revisions to the details shown on the project plans. The
Contractor shall obtain the Engineer's approval of any changes necessary for proper crossing of
existing utilities. The revisions will be directed by the Engineer and will not be the basis for a Change
Order Request unless the revisions necessarily increase the cost or time to perform the work.
3.14 INSPECTION
All work shall be subject to inspection by the appropriate City departments at all times, and as
further specified in the Contract Documents, including the General Conditions. Any work concealed
before it has been inspected by the Engineer shall, at the request of the Engineer, be reopened or
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uncovered at the Contractors expense. If deficiencies are found, these deficiencies shall be
corrected at the Contractor's expense. In addition to the payment provisions in Article 9 of the
General Conditions, the Contractor shall meet with the City Inspector at the end of each billing
period to quantify the work performed for each bid item.
The City reserves the right to inspect all materials or equipment during the production,
manufacturing or fabricating process, before shipment, or when delivered to the site.
Neither acceptance of the work, nor final payment, shall relieve the Contractor of the responsibility
for performing the work in accordance with the contract requirements. The Contractor shall remedy
any work not conforming to the contract without expense to the City.
Contractors working on City CIP projects shall pay for the City Inspector’s overtime at 1.5 times the
Council approved inspection rate if work is performed beyond the established construction hours,
unless the overtime work is requested by the City. Construction hours for Utilities CIP projects are
8 AM to 5 PM, Monday through Friday, unless otherwise specified.
Contractors working on private development projects shall pay all inspection costs including the
City’s WGW Utility Inspector’s overtime at 1.5 times the Council approved inspection rate for
inspections scheduled outside the hours of 8:00 AM to 3:00 PM Monday through Thursday
excluding City holidays.
3.15 LICENSES, PERMITS AND FEES
The Contractor shall apply, procure, and pay for all licenses and permits, including but not limited
to CPA street-work permit, encroachments permits (including but not limited to the following
agencies: Caltrans, VWD, SFPUC, Caltrain, Santa Clara County, PG&E, Stanford, VTA, and etc.),
water use, electricity, building permit, noise exception permit, storage of materials, office trailer,
erection of construction shack, etc. required by the City or other government jurisdictions or
agencies. The City will pay for other agency’s inspection fees, unless the fees are related to
damage caused by the Contractor.
The Contractor is responsible for obtaining, at its sole expense, any licenses required by the
contract documents, including the Special Provisions in the Invitation for Bid package. Prior to
submitting the bid, the Contractor shall conduct research of each agency’s specific requirements
to perform work within the agency’s right-of-way or near the agency’s utility; Contractor’s bid will be
deemed to include sufficient costs in the bid to comply with all applicable permit requirements. The
Contractor shall include all associated costs and anticipate potential long lead time to comply with
each agency’s requirements. The Contractor shall provide the City with copies of permits and
licenses.
For any work in railroad’s right of way, the Contractor shall pay for the costs incurred by the railroad
company such as inspectors’ wages, safety flagman’s wages, safety training, and rail supports if
necessary.
Contractor’s bid is deemed to include all costs and expenses for such licenses and permits. No
other compensation shall be paid to the Contractor for these items or for delays caused by non-
City inspectors or conditions set forth in the licenses or permits issued by other agencies.
3.16 PROTECTION OF TREES, PROPERTY, AND SERVICE STRUCTURES
Trees, shrubbery, fences, poles and other property and service structures shall be protected,
unless their removal is shown on the drawings or authorized by the Engineer. Trees shall be
protected per the City of Palo Alto Tree Protection Manual.
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Where the City (street) trees obstruct the Contractor's equipment, the Contractor shall be
responsible for all trimming necessary to create clearance for his or her operations. Trimming shall
be done by a certified tree worker or a qualified tree care specialist in accordance with the City of
Palo Alto Public Works Standard Drawings and Specifications. The City Arborist shall be notified
in advance of all branch and tree roots greater than 2 inches in diameter which need to be trimmed
or removed. The trimming or removal of these limbs or tree roots shall be approved by the Arborist
prior to removing.
When performing boring operation below a tree with a tap root, the minimum depth of boring shall
be 5' below the ground elevation.
The Contractor will be assessed charges for any damage to City trees including, but not limited to,
broken limbs and damaged trunks. Charges will be determined by the City Arborist. Any damage
to private trees including, but not limited to, broken limbs and damaged trunks shall be remedied
to the homeowners’ satisfaction.
3.17 ASPHALT CONCRETE PAVING
Place asphalt concrete in accordance with the City of Palo Alto Public Works Standard Drawings
and Specifications, and Caltrans Standard Specifications. Section 17 (Boring, Trenching and
Potholing) of the Public Works Standard Drawings and Specifications lists the requirements for
street restoration for both open cut and directional drilling/pipe-bursting installation in streets,
restoration for both improved and unimproved areas, and required limits of trench restoration. The
minimum pavement section restored shall be two (2) inches asphaltic concrete on eight (8) inches
of Class 2 aggregate base, or the existing pavement and base section, whichever is greater. Class
II aggregate base shall be compacted to 95% compaction.
Prior to asphaltic concrete pavement installation, all debris (leaves, twigs, trash, etc.) laying on the
top of the compacted trench shall be removed and paint binder (RS-1) shall be applied to all vertical
edges of the surrounding pavement around the perimeter of the trench at a rate of 0.05 to 0.10
gallons per sq. yd. Do not commence placement of asphaltic concrete materials when the
atmospheric temperature is below 50o F, or during fog, rain, or other unsuitable conditions.
The new asphalt concrete shall be placed to the same grade as the surrounding asphalt concrete
grade, such that the originally designated cross-sectional geometry of the road is maintained.
Excess asphalt shall be removed from the working area and not rolled into the mat. Asphaltic
concrete shall be placed with an asphaltic paving machine. A paving box may be used only with
the approval of the Engineer. A maximum of a 3 inch lift is allowed for asphalt concrete pavement.
Final lift of asphalt for trench restoration shall be 3/8" fine.
Upon completion of all asphalt paving, a seal coat (fog seal or sand seal) shall be applied to all
restored surfaces. On streets with slurry seals, the restored trench shall receive a slurry seal coat
in accordance with Section 37-2 of the California Specifications.
Unless otherwise authorized by the Engineer, all construction and restoration shall be completed
within fifteen (15) working days from start of work at any specific location, and final surface
restoration shall be completed within ten (10) working days from the last day pipe was installed on
any particular continuous section. No more than 1,000 feet of temporary pavement will be allowed
before the contractor must install permanent paving prior to proceeding with new trenching
operations.
3.18 PCC PAVEMENT, CURBS, GUTTERS, SIDEWALKS, AND DRIVEWAYS
Place Portland cement concrete and PCC pavement in accordance with the Public Works Standard
Drawings and Specifications, and Caltrans Standard Specifications.
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EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 15
The PCC plug shall be placed to the same grade as the surrounding PCC pavement grade, such
that the originally designated geometry of the roadway is maintained. Excess concrete shall
immediately be removed from the working area and disposed of properly. After placing, the
concrete shall be consolidated sufficiently to produce a dense mass, struck off and floated.
All concrete shall be placed against existing sawcut concrete or 2" thick wood forms. If a gutter
exists, twelve inches of AC will have to be removed at the lip of gutter for the placement of these
forms. No concrete shall be placed against asphalt or spalled/broken concrete.
Forms shall be checked by the WGW Utilities Inspector and Public Works Inspector before any
pouring of concrete. PCC shall not be poured when air temperature is below 40 Deg. F or during
rain or within two hours before sunset. No on-site mixing of PCC shall be allowed.
All new PCC (at sidewalks, curb and gutter, and concrete roads) shall be doweled into existing
PCC using #4 rebar 12" long dowels spaced at a maximum of 2' centers. Dowel holes shall be
drilled in the vertical section center. Dowel holes shall be drilled 6" into the existing concrete without
causing damage. Dowels shall be epoxied into the existing concrete.
Concrete shall be placed and compacted in forms without segregation. After placing, the concrete
shall be consolidated sufficiently to produce a dense mass, struck off and floated. Final finishing
operations shall not proceed until all bleed water has evaporated from the surface. Sprinkling of
dry cement to absorb excessive surface moisture shall not be allowed. The surface texture of
finished concrete shall conform to adjacent concrete. Forms shall not be removed less than twenty-
four hours after the concrete has been placed. In no event shall forms be removed while the
concrete is sufficiently plastic to slump.
If any portion of sidewalk is sawcut or damaged during the course of work, the Contractor will be
required to remove and replace the entire width of sidewalk from the planting strip or property line
edge of the walk to the curb edge between the nearest undamaged joints.
As soon as the concrete is set, it shall be cured for a period of at least 72 hours by spraying with
an approved pigmented impervious membrane-curing compound.
The Contractor shall protect from damage all completed Work. All discolored concrete shall be
cleaned to a uniform color. Repairs and cleaning of new concrete shall be at the expense of the
Contractor.
3.19 PAVEMENT STRIPING AND LEGENDS
Contractor shall replace all pavement striping, legends, signs, and curb painting damaged due to
the Contractor’s activities in kind unless a redesign is ordered by the Engineer. Place pavement
striping, legends, signs, and curb painting in accordance with the Public Works Standard Drawings
and Specifications, and Caltrans Standard Specifications.
Temporary traffic striping and legends shall be placed on the newly paved street prior to the release
of the street to the public. These materials shall be either pop-up temporary markers (for arterial
streets) or tape (for residential streets). The proposed materials must be submitted to the Engineer
for approval prior to use. Permanent striping must be installed within seven (7) days.
Alignment lines shall be established by the application of cat tracks or dribble lines, the use of laser
guidance devices or a combination of both, as detailed in the Caltrans Standard Specifications.
Pavement markers and Stimsonite fire hydrant markers shall be placed in accordance with the
Caltrans Standard Specifications and manufacturer's installation procedures.
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EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 16
Tape striping, legends, signs, markings, or other facilities removed or damaged during construction
shall be repaired or replaced in kind at no expense to the City within ten (10) working days of the
last day pipe was installed on any given continuous section.
All materials, equipment and labor required to perform surface restorations shall be included in one
or more of the bid items and no further compensation will be allowed for surface restoration.
Thermoplastic material and paint for traffic stripes and pavement markings shall be applied in
accordance with the California Standard Specifications, Section 84, and manufacturer's installation
procedures.
Tape shall be applied using a mechanical applicator furnished by the tape vendor. Installation shall
be in accordance with the manufacturer's recommended installation procedures.
3.20 TRAFFIC LOOPS
In the event the Contractor severs any part of a traffic loop, the Contractor is responsible for
replacing the entire traffic loop at the Contractor's expense, in accordance with the following
standards:
A. The Contractor shall replace the affected loop within 72 hours following the completion of the
surface restoration on the affected street. If this replacement is not done by this deadline, this
work will be done by the City at the Contractor's expense.
B. The Contractor shall coordinate all signal loop work with the City Traffic Signal Division.
C. Loops shall conform to City of Palo Alto wiring diagram quadrupole detector loops, Drawing K-
1184. Each loop shall be identified in the pull box as to location, I.E. "2WR" or "2WL".
D. No separate bid item is made for the cost of replacing or repairing any traffic loop. It is the
contractor’s responsibility to determine the expense of potential damage to traffic loops and
include cost in the bid items.
E. Diagrams for City owned traffic detection loops are available from the City of Palo Alto
Transportation Division of the Planning Department. For non-City owned traffic detector loops,
contact the appropriate agencies (Caltrans, Santa Clara County, etc.)
3.21 LANDSCAPING AND MISCELLANEOUS
All monuments within the project site shall be preserved as required by the State and local
regulations. Damaged or destroyed monuments shall be replaced by a California licensed Land
Surveyor hired by the Contractor. The Contractor shall submit the method and procedures of tying
out the monuments for the City Surveyor’s approval. The Contractor shall also provide a recorded
copy of the “corner record” to the City Surveyor. No separate bid item was made for the cost of any
surveying or monument replacement work. The cost shall be included in one or more bid items.
The Contractor shall restore any special surface treatments encountered in the execution of this
Work to an equivalent or better condition than existed prior to the commencement of this Work.
After each site has been completed, the Contractor shall restore landscaping and areas abutting
the work to the condition existing at the start of work. All materials, equipment and labor required
to perform surface restorations shall be included in one or more of the bid items and no further
compensation will be allowed for surface restoration.
END OF SECTION
48
POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 1
SECTION 2300
POLYETHYLENE PIPE INSTALLATION
FOR WATER, GAS AND WASTEWATER
PART 1 – GENERAL
1.01 DESCRIPTION
Work includes fusion and installation of 1” and greater medium and high density polyethylene
services and mains, all appurtenances and all related equipment and fittings in accordance with the
requirements of the Contract Documents.
1.02 RELATED WORK
A. Section 2200: Excavation, Backfill and Restoration
B. Section 2660: Water Design and Construction Standards
C. Section 2685: Natural Gas Distribution System
D. Section 2735: Polyethylene Sewer Pipe
E. Section 2737: Sanitary Sewer Lateral
1.03 POLYETHYLENE PIPE
A. Gas: 2708 medium density polyethylene (MDPE), uniformly yellow in color. Pipe wall thickness
shall be 0.099” minimum for 1” CTS, SDR 11 for 2” IPS pipe, and SDR 11.5 for 3” through 8” IPS
pipe. Refer to Section 2685 of these Standards for additional requirements. 1” CTS and 2” IPS
pipe shall be supplied in coils. The coils shall be furnished in either 500 or 1,000-foot lengths
specified at the time of order (2” straight 20’ or 40’ lengths can be used for shorter services and
connections).
B. Water: 4710 high density polyethylene (HDPE). Pipe wall thickness shall be SDR 9 for 2” IPS
pipe and SDR 11 for 4” and greater IPS pipe. All water main pipes shall be black with four (4)
longitudinal blue single stripes evenly spaced. Solid blue pipe may be acceptable if the pipe
meets Standard Specifications Section 2660 and with prior approval. Refer to Section 2660 of
these Standards for additional requirements. 2” IPS pipe (water services) shall be supplied in
straight lengths only.
C. Wastewater: 4710 high density polyethylene (HDPE). All wastewater main pipes shall have
white, grey, or light-colored interior. The exterior color can be black or grey with four (4)
longitudinal green single stripes evenly spaced. Solid green exterior color is acceptable if the
pipe meets Standard Specifications Section 2735 and with prior approval. Pipe wall thickness
shall be SDR 17. Refer to Section 2735 of these Standards for additional requirements.
Pipe 4” IPS through 18” IPS shall be supplied in 40 foot or longer straight lengths. Straight lengths
shall consist of a single length of pipe without couplings or any intermediate joints.
Pipe markings shall be in a color that contrasts with that of the pipe and space at intervals not
exceeding two (2) feet. All required markings shall be legible and so applied as to remain legible
under normal handling and installation practices. These markings shall consist of the Utility (GAS,
WATER or SEWER), the designation (ASTM D2513 (gas), cell classification confirming to the latest
ASTM D3350 234373E (gas), 445574C (water), indicate listing under ANSI/AWWA C906 (water),
the manufacturer's name or trademark, the nominal pipe or tubing size (including the sizing system
used, such as, IPS, CTS or OD), the type of material, SDR number, the month and year of
49
POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 2
manufacture, and identification of resin supplier (if other than pipe manufacturer), and manufacturer
(P for Performance Pipe, or I for Ineos, etc.).
All pipe shall be made of virgin quality material and be homogeneous throughout and free of visible
cracks, holes, foreign inclusions, blisters, dents, and other injurious defects. No reworked material
shall be allowed. The pipe shall be as uniform as commercially practicable in color, opacity, density,
and other physical properties.
Black polyethylene water pipe, yellow polyethylene gas pipe, and black or grey polyethylene sewer
pipe (inner wall shall be white or light in color) shall be no older than six (6) months from the date of
manufacture to the date of arrival to CPA. All pipes shall be packaged in standard commercial coils
or bundles that provide protection from shipping injuries and shipped with pipe caps. When storing
the pipe on site, the Contractor shall protect pipe from direct sunlight by UV resistant cover. All pipe
must be installed within 3 years of the manufactured date.
1.04 POLYETHYLENE FITTINGS
All polyethylene fittings shall have butt end outlets. Molded and fabricated fittings shall have a
pressure rating equal to the pipe. Minimum pipe wall thickness for fitting butt outlets shall be equal to
the pipe wall thickness.
All fittings shall be made of virgin quality material and be homogeneous throughout and free of visible
cracks, holes, foreign inclusions, blisters, dents, and other injurious defects. No reworked material
shall be allowed. The fittings shall be as uniform as commercially practicable in color, opacity,
density, and other physical properties.
Fittings shall be molded, except fittings larger than 12”, which are allowed to be factory fabricated
(unless molded fittings are available). Fabricated fittings shall be fabricated on machinery specifically
manufactured for that purpose. Fabricated fittings shall be manufactured using Data Loggers
recording heating iron face temperatures, fusion pressure and a graphic representation of the fusion
cycle. The Data Logger printout shall be part of the required submittal for the fabricated fitting.
Fabricated fittings shall be manufactured by ISCO or approved equal. All fabricated fittings must be
approved by the Engineer prior to installation.
Gas fitting marking shall be in compliance with ASTM F2897-14 Standard Specification for Tracking
and Traceability Encoding System of Natural Gas Distribution Components (Pipe, Tubing, Fittings,
Valves, and Appurtenances) and consist of 16-digit alpha-numeric code and scannable code 128
barcode, or QR code, which standardizes encoding of pipe specifications as described in the
referenced Standard.
In addition to the compliance with the requirements of ASTM F2897-14, gas fitting markings shall
also comply with the marking requirements for all polyethylene fittings specified in this Section as
stated below.
Fittings shall be marked with the following: ASTM D3261 (Butt type); manufacturer's name or
trademark; material designation; date of manufacture or manufacturing code; size (including the
sizing system used, such as, IPS, CTS or OD). Where the fitting size does not allow complete
marking, marking may be omitted in the following sequence: size, date of manufacture, material
designation, and manufacturer's name or trademark.
PART 2 – MATERIALS AND INSTALLATION
2.01 POLYETHYLENE PIPE JOINING EQUIPMENT
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POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 3
All polyethylene pipe joining equipment to be used shall be certified by the City of Palo Alto to be in
good working condition and suitable for the intended purpose prior to being brought on site. Any
equipment without a City issued certification tag shall be removed from the site. The Contractor shall
have all equipment necessary to install the pipe and appurtenances referred to in the Plans and
Specifications, including but not limited to:
A. Pipe Trailer: Contractor shall provide a trailer capable of transporting 40' or longer lengths of
polyethylene pipe without damaging pipe.
B. Pipe Spool: Contractor shall provide a reel type spooling device capable of dispensing 500' long
2" polyethylene pipe coils. Spool can be trailer mounted or suspended from a truck or backhoe
(SpeedReel).
C. Pipe Support Stands: Pipe support stands shall be utilized to support pipe during fusion joining,
directional boring pull in, and while lowering of the pipe into the trench. Pipe support stands shall
not be spaced greater than 15' apart for directional boring pull in. Pipe shall be supported with
stands at all times and not placed on pavement to avoid scratching the pipe surface.
Additionally, manufactured pipe support stands outfitted with rollers shall be used at the
pavement or plate edge where pipe is pulled into the trench/bore hole to avoid scratching of the
pipe.
D. Pipe Cutter: Pipe cutter for polyethylene pipe shall be:
x For 2” – 12” diameter pipe guillotine style pipe cutter outfitted with a ratchet drive or power
driven designed to cut medium/ high density polyethylene pipe. For 6”-12” diameter pipe
PLAS In-line Rotary cutters manufactured by Reed Pipe Tools & Vises
(www.reedmfgco.com), or approved equal.
x For pipe larger than 12” PLAS In-line Rotary cutters manufactured by Reed Pipe Tools &
Vises (www.reedmfgco.com), or approved equal.
No other cutting tools will be allowed unless approved by the Engineer.
E. Butt Fusion Machine: Contractor shall provide McElroy or approved equal butt fusion
machine(s) capable of fusing the range of pipe sizes required in the contract/plans with the
following features:
1. Butt Fusion Machine: Machine shall be the hydraulic fusion machine with built-in hydraulic
pipe lift to assist with the pipe handling and incorporating centerline guidance system and
DataLoggerTM compatible, and capable of butt fusion of most fittings without special holders
or removal of jaw.
2. Facer: Pipe facer that attaches to the butt fusion machine. Facer shall have sharp properly
aligned blades.
3. Heating Iron: Electrically powered heating iron with unscratched clean Teflon coated faces.
Heating iron shall have a thermometer and temperature set screw for calibration.
F. Electrofusion Machine: The Contractor shall provide a Friatec universal electro fusion control
box or approved equal, capable of storing a minimum of 100 fusion records, pipe alignment
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POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 4
clamp, tapping tee alignment clamp, tapping wrench, pipe scraper, and all other tooling specified
by the electro fusion machine manufacturer installation procedures.
G. Electric Generator: Contractor shall provide the necessary power supply to meet the power
requirements as specified by the manufacturer of the fusion equipment. Generator shall be in
new condition and have a minimum rated capacity of 5 kW for 8” and smaller and 10 KW for 10”
and larger.
H. Pyrometer: The Contractor shall provide a pyrometer capable of testing the temperature of the
heating iron, while at fusion temperature, to an accuracy of 0.5% (r3qF). The fusion temperature
of the heating iron shall be verified each morning in the presence of the WGW Inspector. More
frequent testing may be required at the discretion of WGW Inspector.
Note: The Contractor shall keep a binder on site containing the fusion procedures, names of
approved fusers and serial numbers of the approved fusion equipment. All equipment must be in
good working order and properly maintained during project installation. The City will inspect the
preceding items and reject those not in compliance. The City shall have the right to reject any or
all equipment judged inadequate to properly fuse polyethylene pipe and its fittings.
2.02 POLYETHYLENE PIPE INSTALLATION PARAMETERS
The City will test to qualify all person(s) intending to make polyethylene joints by fusion. The persons
will be allowed to perform fusion only for the utility (water, gas or wastewater) they were qualified.
The fusers must be requalified at the start of any new project, regardless of whether or not the fuser
was certified previously on another project. A minimum of two certified fusers shall be on-site at all
times during fusing operations and all fusions must be conducted in the presence of or with the prior
approval of the City's WGW Inspector.
Applicants for testing will need to demonstrate a working knowledge of PE fusion and equipment
without any guidance, including setting up the equipment, verifying the proper settings, and
completing a test fusion sample. All testing procedures are based on the ASTM F2620 current
revision standard. Applicants will have one opportunity to pass the test per day. If the test is failed,
another test will not be administered for a minimum of 5 days.
At the Contractor’s expense, the Contractor’s employees who perform fusion on the projects will be
required to attend a fusion class conducted by a certified pipe or equipment manufacturer. Proof of
attendance will be required when scheduling fusion testing with the City-authorized testing company
or personnel. If construction is expected to last more than one year, the Contractor’s employees who
perform fusion will also be required to attend annual fusion training classes. Proof of attendance shall
be submitted to the Engineer within one year of the original certification date. See Section 2400
(HDPE Water and Sewer Pipe – Fusion Training Procedures and Certification) and Section 2500
(Polyethylene Gas Pipe Fusion Training Procedures and Certification) for additional testing
requirements.
The Contractor’s employees will perform the qualification testing at the yard of City-authorized testing
location. The Contractor shall bring his own equipment and materials to be used on the project for
testing (including but not limited to generator, fusion machines, scrapers, etc.). The Contractor will be
required to schedule fusion testing four (4) weeks prior to the start of Work. The Contractor shall
coordinate testing schedule with City-authorized testing company or personnel and provide them with
two (2) weeks advance notice.
The City will test the Contractor’s fusers once at no cost to the Contractor. Contractor shall send all
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POLYETHYLENE PIPE INSTALLATION SECTION 2300
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potential fusers for the project to the test at the same time. If any of Contractor’s fuser fails to pass
the first qualification test, the City may charge the Contractor for time spent retesting each fuser. The
Contractor is responsible for any delays in meeting Contract requirements that is attributed to
retesting of the Contractor’s fusers. No additional contract days, or monies, will be given due to
retesting.
A. Underground Clearance: Unless otherwise specified on the Project Drawings or approved by
CPA Utilities Engineering, the proposed pipe shall have at least 18” vertical clearance to crossing
sewer mains, 12” vertical clearance (outside wall to outside wall of fittings/pipe/structure) to
other crossing utility lines or structure, and 48” horizontal clearance to parallel utility lines, duct
banks or adjacent foreign structures. The clearance should be measured from outside wall to
outside wall of fittings/pipe/structure. In the case of new water construction, the separation
between new water mains and existing sewer mains shall be at least 10-feet horizontally and 1-
foot vertically per Regional Water Quality Control Board (RWQCB) requirements. If the 10-feet
horizontal or 1-foot vertical clearances are not attainable, the RWQCB will need to review and
approve the plans. For all other utilities, if horizontal separation is less than 4’, review and
approval by CPA Utilities Engineering is required.
B. Configuration: Contractor shall install mains and services as follows:
1. Mains and services shall be configured per WGW Utilities standard drawing WGW-01,
unless otherwise specified on the Project Drawings.
2. Services shall be installed perpendicular from the main in the shortest straight line to the
meter or clean out, if possible. Water meters, services and sewer laterals shall be installed
10' minimum from trees, if possible.
Handling of Polyethylene Pipe: Extreme care must be exercised when moving plastic pipe.
POLYETHYLENE PIPE SHALL NOT BE DRAGGED ON THE GROUND OR ON PAVED
SURFACES. Support stands and rollers must always be used to keep the pipe above paved
surfaces/ground level, including but not limited to fusing, transporting, lowering pipe into the
trench or bore hole, during directional boring pull-in or pipe-bursting operations, etc.
C. Pipe Scratches or Cuts: Pipe that has scratches, notches, cuts or any other abrasions that
exceed ten percent (10%) of the gas/water pipe wall thickness, or 20 percent (20%) of the sewer
pipe wall thickness, shall be disposed of. The Contractor shall use pipe stands, rollers, spooling
devices, or other means to avoid damaging the pipe during installation. Observe pipe during
installation for scratches, gouges or other defects. If defects are present, remove and discard
defective sections of pipe. The WGW Inspector must be notified of all defects and subsequent
repairs. The Contractor is responsible for the cost to replace damaged pipe if it is a result of not
using stands, rollers, spooling devices, or other means to protect the pipe during installation.
D. Pipe Squeeze Off Tools: Manual squeeze off tools can be used for pipelines with diameter of
½”CTS – 2”IPS. Hydraulic squeeze off tools are necessary for pipelines with diameter of 3”IPS –
8”IPS. These tools should be equipped with stops for each size to prevent over squeezing of the
pipe.
E. Snaking Pipe: Polyethylene pipe shall be installed in the trench by “snaking” method and
additional pipe length shall be allowed for the possible thermal contraction of the pipe.
F. Maximum Pull Force: A commercially available weak link approved by the Engineer for the
specific application shall be used, in accordance with manufacturer’s recommendations, between
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POLYETHYLENE PIPE INSTALLATION SECTION 2300
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the puller and the pipe, for water and gas construction. See Section 2.03.A.4 for maximum pull
forces.
G. Butt Fusions: All butt fusions shall be performed by the Contractor as follows:
1. All butt fusions must be performed by the person(s) qualified and certified by the City to butt
fuse in the presence of the City's WGW Inspector. Fusion qualified Contract employees
found to not be following manufacturer’s guidelines or performing fusions with inadequate or
defective equipment will have their fusion qualifications revoked and will not be allowed to
perform fusions for the remaining duration of the contract.
2. Pipe fusion shall be conducted in accordance with the manufacturer’s recommended fusion
procedure and in compliance with the most current version of ASTM F2620, PPI Technical
Report TR-33, and in accordance with the "City of Palo Alto, Polyethylene Pipe Fusion
Training Procedures". See Sections 2400 and 2500 of the City of Palo Alto Water, Gas, &
Wastewater Utility Standards.
3. Ambient temperature shall be between 55° F and 85° F prior to pipe fusion; otherwise pipe
shall be protected from direct sunlight and cooled down until the ambient temperature falls
within the above temperature range.
4. Fusion joints shall be allowed to cool for the times recommended by the pipe manufacturer
prior to any movement of the fused joint.
5. All non-manual fusions shall be made using a Data Logger recording heating iron face
temperatures, fusion pressure and a graphic representation of the fusion cycle. The Data
Logger data shall be reviewed by Inspector prior to pipe being pulled in. Data Logger
records shall be uploaded daily to a cloud server for remote viewing from any location.
H. Inspection: The following is a list of inspection duties both required of the City and Contractor:
1. The City will provide a polyethylene certified Inspector at the job site. The Inspector has the
right to reject any fusions not meeting City requirements. The Contractor shall replace all
fusions not meeting City requirements at its own expense.
2. In addition to the City certified fusers, the Contractor shall also provide a City certified
polyethylene fusion supervisor who will be present on site at all times to inspect, guide,
advise, ensure that all required procedures are adhered to, to witness the quality of each
joint, and to observe pipe fuser(s) as they work. The Contractor’s supervisor will be
responsible for inspecting all fusions performed. As with the City certified fuser, the fusion
supervisor will be tested and qualified by the City.
3. At the City's discretion the Contractor will remove fusion(s) and supply it to the City for
testing to ensure quality control.
4. Fusion records shall be downloaded and provided to the City in electronic format on a weekly
basis. Records of all non-manual butt fusions shall be uploaded daily to the cloud server.
The City may require paper record copies on a weekly basis.
Records of all non-manual butt fusions shall be uploaded daily by the Contractor to the cloud
server, in a sub-account to be created by the City for the Contractor, under the City’s
account. City will provide Contractor login info. The City may require paper record copies of
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POLYETHYLENE PIPE INSTALLATION SECTION 2300
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manual fusions.
5. Any failure recorded by the fusion equipment must be immediately brought to the attention of
City’s Inspector to avoid the City requiring the contractor to remove fusions to the last
recorded acceptable fusion.
6. The fusion number corresponding to each joint shall be written on the pipe at the fusion
location with an indelible marker.
7. Fusion number(s) shall also be noted on the Contractor’s record drawing at the approximate
location(s) of the fusion for both water and gas installation.
8. The City’s Inspector will observe plastic fusions and reject all connections which are
deficient. All fusions must be conducted in the presence of or with the prior approval of the
City's WGW Inspector. The City’s Inspector will review the Data Logger or non-destructively
test plastic fusions and reject all connections that are deficient. The contractor will replace all
fusions failing non-destructive testing at his expense. The contractor will replace all fusions
failing visual inspection or non-destructive testing at his expense.
I. Sealing Installed Piping: Contractor shall seal open all water and gas piping with butt fusion
end caps at the end of each workday. No open pipe ends (or ends sealed with tape) will be
allowed at the end of the day.
J. Minimum Bending Radius: The minimum bend radius for polyethylene water pipe SDR 9 is
twenty (20) times the outside pipe diameter, for SDR 11 is twenty five (25) times the outside pipe
diameter, and for SDR 17 is twenty seven (27) times the outside pipe diameter. If fusions, fitting,
or flange are present or to be installed in the bend, the minimum bend radius shall be one
hundred (100) times the outer pipe diameter.
2.03 POLYETHYLENE PIPE INSTALLATION METHODS
A. BORING
The Contractor shall not change the installation method from direction boring or pipe bursting to
open trench without the Engineer’s approval. See WGW Utility Standards Section 2735 for
sanitary sewer projects.
The pilot bore for utility mains and services shall be a minimum of 24" clear from other
underground facilities. The Contractor shall install pipe by directional boring method only when a
minimum of 24” separation is achieved, unless otherwise approved by the Engineer.
1. Boring Machine
The contractor shall provide a utility line boring machine(s) capable of installing 1" thru 8" pipe by
directional boring.
a. Service Line Boring Machine: The contractor shall provide a boring machine or pneumatic
gopher capable of installing 1", 1-1/2", and 2" pipe.
b. Directional Boring Machine. The Contractor shall provide a directional boring machine
capable of drilling a pilot hole along a predetermined path to a specified target location, then
enlarge the pilot hole to desired size while pulling in specified size pipe. The boring machine
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POLYETHYLENE PIPE INSTALLATION SECTION 2300
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shall be equipped with mechanical and hydraulic deviation equipment capable of changing
the direction of pilot drilling course. The boring machine shall also include a fluid
mixing/pumping system capable of lubricating the bore hole with drilling fluid to insure
complete consolidation of the soil after pipe installation and to minimize friction forces during
pull back.
c. Locating System. The Contractor shall provide a locating system able to monitor the location
and orientation of the drilling head assembly along a predetermined course. The locating
system shall be capable of locating the drill head both horizontally and vertically to an
accuracy of ± 1" at 10' depth, and detect the rotation angle of the head.
d. Compaction/Reaming Devices Management. The Contractor shall be responsible for
selection of the method(s) of expansion of a pilot hole, if required, and assume full and sole
responsibility for location and protection of the existing underground facilities as specified in
Subpart 3.08 of this specification.
e. Maximum diameter of the pilot drill bit shall not exceed 3.5 inches in diameter, unless
approved by the Engineer.
2. Directional Boring Method
a. Drill a pilot hole with fluid assisted mechanical cutting head along a predetermined path to a
specified target location. Drilling fluid can be a mixture of water and bentonite, polymers, or
other approved additives. No fluid shall be discharged into the streets, gutters, or sewers.
Fluid pressure and flow rate shall be minimized through the use of relief holes during the
drilling operation to prevent fracturing the subgrade material around and above the pilot hole.
Uncontrolled jetting is prohibited. Any fluid discharged onto streets, sidewalks or customer
property, shall be properly disposed of including cleaning of the affected area. Excess drilling
fluid must be removed from the surface of relief holes prior to paving.
b. Enlarge pilot hole with cutters or reamers to desired size and pull in specified size pipe while
injecting fluid mixtures to hold reamed hole open and lubricate the utility line being pulled.
Reamer sizes are listed below.
Pipe size
(in.)
Minimum Reamer Size
(in.)
2 4
4 8
6 12
8 14
10 and 12 18
>12 >50% of pipe diameter and approved by the Engineer
A commercially available weak link approved by the Engineer shall be used between the
puller and the pipe, in accordance with manufacturer’s recommendations, no matter the
material or size of the pipeline being pulled.
c. The Contractor will be allowed to leave drill rods in the ground overnight, however pipe
pulling must be completed on the same day as it is initiated. Prior to pipe pulling, an end cap
and tracer wire must be attached.
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POLYETHYLENE PIPE INSTALLATION SECTION 2300
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d. The Contractor is required to protect pipe from scratching and gouging on edges of trench,
plates or pavement during pull in. Rollers shall be used at all bend points in the launching pit
and every 15’ along the pipe. Methods of protection shall be submitted for review and
approved by the Engineer prior to performing the Work. Dragging of the pipe on paved
surfaces is not allowed.
e. After the pipe is pulled in, verify the lead edge of pipe is free of gouges greater than 10% of
the pipe wall thickness. Check continuity of tracer wire to ensure tracer wire remained intact
during pull in.
f. Pressure test pipe with air or water per the respective utility.
3. Bore and Jack
At railroad and major street crossings where open excavation cannot be made, a steel
casing shall be installed by boring and jacking after permitting and coordinating with agency
having jurisdiction. The grade shall be as shown on the Plan and Profile drawings and the
casing shall be installed to permit the carrier pipe to be spaced as shown in the drawings.
The size of the casing shall be as specified in the Drawings and Specifications. Link Seals
or approved equal, shall be installed at both ends of the casing and manufactured casing
insulators shall be installed at 5 foot maximum intervals on the carrier pipe prior to insertion
as shown on the project drawings.
Joints between sections of the casing shall be welded for the entire circumference of each
joint. This weld shall be a minimum of two complete passes.
The contractor shall furnish casing for locations shown on the Plan and Profile drawings. If
for convenience of construction, the contractor should select to install casings at locations
other than those shown on the Plan and Profile drawings, he or she may do so at his/her
expense provided the Engineer approves and required permits allow installation at the new
locations.
Note: All equipment must be in good working order and properly maintained during project
installation. The City will inspect the preceding items and reject those not in compliance. The
City shall have the right to reject any or all equipment judged inadequate.
4. Maximum Pull Force
The allowable tensile load is calculated based on fY = 0.40; fT = 1 hour; TY @ 100 qF. Refer
to Section 2300.1.03 for SDRs for each type of pipe.
i. MDPE 2406 (gas pipe):
Pipe size
(in.)
Maximum Allowable Pull Force
(lb.)
1 300
2 1,600
4 4,640
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POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 10
6 10,060
8 17,060
ii. HDPE 4710 (water or gas* pipe):
Pipe size
(in.)
Maximum Allowable Pull Force
(lb.)
2 2,020
4 6,090
6 13,210
8 22,390
10 34,780
12 48,930
14 59,000
16 77,060
18 97,530
*HDPE gas pipe shall only be used for special cases upon Engineer’s request and approval.
iii HDPE 4710 (sewer pipe):
Pipe size
(in.)
Maximum Allowable Pull Force
(lb.)
4 4,080
6 8,850
8 15,000
10 23,300
12 32,780
14 39,520
16 51,620
18 65,330
20 80,660
iv Steel Pipe pull forces shall be approved by the Engineer prior to pulling.
B. DIRECT BURIAL
1. Excavate to the required depth and ensure trench bottom is level and free of sharp objects,
rocks, or other materials that may damage pipe. Shade excavation with 4” to 6” sand or ½”
crushed rock bed and level sand or crushed rock as needed. Refer to Utility Standard Detail
WGW-02 for bedding requirements.
2. Install pipe in excavation, with #10 tracer wire on top, and snake pipe. Observe pipe during
installation for scratches, gouges, or other defects. Avoid dragging pipe over rough surfaces.
3. Backfill to top of pipe with sand or ½” crushed rock and haunch the sides. Continue
backfilling pipe with sand or ½” crushed rock to 12” above top of pipe and install warning
tape. Backfill remaining excavation in 12” lifts and compact to 95% compaction.
END OF SECTION
58
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 1
SECTION 2400
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER)
7/19/21
TABLE OF CONTENTS
PAGE
SUBJECT NUMBER
Heat Fusion Tools 2
Manual Butt Fusion Procedure (City Staff Only) 4
Hydraulic Butt Fusion Procedure 7
Electro Fusion Procedure 7
Requirements for HDPE Fusion Testing 7
HDPE Fusion Practical Test (Sample) 9
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FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 2
CITY OF PALO ALTO: HDPE Water and Sewer Pipe Fusion Procedures
It is the responsibility of a fuser to verify that polyethylene pipe and fittings are in conformance
with the specifications requirements and no older than 6 months from the date of manufacture to
the date of arrival to CPA for black with blue stripe polyethylene water pipe or grey with green
stripe polyethylene sewer pipe.
A. HEAT FUSION TOOLS
1. BUTT FUSION
NOTE: The manufacturer’s operating instructions must be adhered to insure acceptable fusions.
a. Heating Iron
The heating irons are NOT EXPLOSION PROOF and shall not be used in any area with gas
present while still connected to a power source.
An electrically resistive coil in the heating iron maintains the temperature at a level sufficient for
fusion. The irons operate on 110 volts A.C. with power requirements ranging from 1200 watts
McElroy No. 14 to 1750 watts McElroy No. 28 Auto Mac. Teflon coated faces are utilized on both
sides of the iron. Extreme care must be exercised to avoid scratching the faces; only cotton cloths
should be used for cleaning. The faces are either an integral part of the iron or are detachable and
must be recoated when scratched. A dial type thermometer is placed next to the handle. The iron
temperature can be adjusted by changing the calibration set screw. The heating iron for the Auto
Mac must be connected to the proper outlet on the butt fusion machine, DO NOT attach the iron to
any other source as it does not self-regulate and it will be burned out.
b. Butt Fusion Machine
The butt fusion machine consists of mobile and stationary alignment clamps that hold the pipe
ends during the fusion process. These clamps transfer the force and associated pressure required
to fuse the pipe.
c. Alignment Clamp Inserts
Two sizes of inserts are supplied for the 4" machines (2" and 3" IPS). The No. 28 machine also
has two inserts (4" and 6" IPS).
d. Facer
Either manual or electrical facers are provided for the butt fusion machines. The electrical facers
are NOT EXPLOSION PROOF and shall not be used in any area with gas present.
2. ELECTRO FUSION
NOTE: The manufacturer’s operating instructions must be adhered to insure acceptable fusions.
a. Universal Control Box
This unit controls the fusion process. It processes information received from the optical wand that
is used to determine the fitting manufacturer and appropriate fusion times. It also stores fusion
60
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 3
related information, which can be downloaded for record information.
b. Barcode wand or Hand-held Scanner
This device reads the uniform product code UPC sticker on the fitting.
c. Electrofusion (E.F.) Couplings
A resistant wire embedded in the coupling provides the energy required for fusion.
i. Alignment Clamps
Only required for 2" and larger sizes. These devices align and immobilize the pipe ends and
coupling during the fusion and cool down periods.
ii. Pipe Scrapers
Three types of scrapers are used to remove oxidation and contaminants from the outside pipe
wall prior to electro fusion coupling installation. A paint scraper may be used on 1/2" and 1"
CTS sizes only. Virax type or interior anchored pipe scraper can be used on 1/2" CTS - 6" IPS
sizes. Additionally, full encirclement Scrapers can be used on 2" - 8" pipe sizes.
d. Tapping Tees
The tees also have a resistant wire coil that provides the energy for fusion. They require either a
back up under saddle or a ratchet operated clamp to fix the tee to the main during fusion. A
threaded cutter is included for tapping the main.
i. Service Line Alignment Clamp
When applying the service line to the outlet of a tapping tee an alignment clamp shall be used
to insure that the outlet and the service line are straight. This unit also immobilizes the
coupling during the fusion and cool down periods.
ii. Ratchet Clamp
All pipe sizes require the use of a hold down clamp or backing plate to secure the tapping tee
onto the main during fusion.
3. MISCELLANEOUS TOOLS
a. Pipe Cutters
i. "Plier" type cutters for use on 1/2" CTS - 2" IPS sizes.
ii. A guillotine type cutter shall be used on 3" and larger sizes.
b. Pipe Squeeze Off Tools
i. Manual squeeze off tools are provided for 1/2" CTS - 2" IPS sizes. These tools are equipped
with stops for each pipe size that prevent over squeezing of the pipe.
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FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
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ii. Hydraulic squeeze off tools are necessary for the larger pipe sizes, 3" - 8". These tools are
also equipped with stops for each pipe size.
c. Pyrometer
The pyrometer is used to check the surface temperature of the heating irons. It consists of a hand
held display unit and an attached surface probe.
B. MANUAL BUTT FUSION PROCEDURES (CITY STAFF ONLY)
1. Energize the heating iron. Once the heater has reached maximum temperature, generator cycles off,
check the thermometer for 425° ± 25°F.
At the start of each day, the reading of the dial thermometer shall be checked against the surface
temperature by use of the pyrometer and the heating iron calibration set screw adjusted accordingly
(manual machines only).
NOTE: DO NOT adjust the heating iron for the AutoMac unit as it is regulated (controlled) by the
microprocessor.
2. Install the proper size alignment clamp inserts if required.
3. Inspect the pipe and/or fitting ends and cut off any damaged or flattened portions.
4. Clean each pipe/fitting end with a clean cotton cloth and place them in the alignment clamps. Pipe
ends should overlap the alignment clamps by approximately 1".
5. Place the manual or the motorized facer on the guide rods and bring the pipe ends in contact with it.
Turn the manual facer in the direction of the arrow or turn the motorized facing unit on and apply light
force on the carriage lever to advance the pipe ends. The motorized facer speed will increase when
the pipe has bottomed out.
6. Retract the carriage lever and remove the facer. Discard the strips of material from the pipe ends
taking care not to touch the clean surfaces. Check the discarded strips to ensure that a continuous
length from the entire diameter has been removed.
7. Check alignment of the pipe ends and adjust for high-low if necessary. If an adjustment is made or a
visible gap exists between the pipe ends, repeat the procedures from Step 4.
8. Wipe heater with a non-synthetic clean dry cloth and place it on the guide rod(s) and bring the pipe
ends into contact with it. Maintain a light force on the carriage until a small melt bead forms around the
entire circumference of both pipe ends. Relax the force on the carriage but keep both pipe ends in
contact with the heater and start the melt time cycle. Refer to Table 1 for proper melt times.
9. After the melt time has been observed snap the carriage back (open) and quickly remove the heater
being careful not to hit the melt.
10. Inspect the pipe ends for complete melt. Bring the pipe ends together quickly, DO NOT SLAM,
applying only enough pressure to form a double roll back bead. The proper bead thicknesses are
shown in Table 1. Over-pressuring the melt will cause the bead to overlap itself resulting in a sub-
quality fusion due to displacement of the melt to the OD and ID of the joint leaving a cold ring in the
center. Under pressuring can result in inadequate fusion due to insufficient contact pressure in the
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FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 5
melt area.
11. Maintain the pressure exerted on the fusion area for one minute for 1/2"-4" sizes and for three minutes
for 6". Relaxing the pressure prior to expiration of the cooling time can result in porous fusion
joints.
12. Allow the joint to cool for additional three to four minutes (see Table 1) prior to removal from the
alignment clamps. The pipe can now be handled with care. Complete cooling requires approximately
thirty minutes.
13. Check the melt bead for uniformity and size. If the joint exhibits poor characteristics, determine the
cause, make the necessary corrections, cut out the suspect joint, and repeat the procedure from Step
4.
14. Clean the heater faces with a clean cotton cloth. DO NOT use synthetic cloths or metal implements.
TABLE 1: Manual Butt Fusion Parameters
Pipe Size
Melt Bead
Size
Heating Time
(seconds)
Hold Time
(seconds)
Cooling Time
(minutes)
2" IPS
1/16"-1/8"
15
60
4
3" IPS
1/8"
20
60
4
4" IPS
1/8"
20
60
4
6" IPS
3/16"
30
180
5
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FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 6
Ref: https://isco-pipe.com/wp-content/uploads/2019/10/2018-ISCO_FusionManual_final.pdf
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CITY OF PALO ALTO Section 2400 PAGE 7
C. HYDRAULIC BUTT FUSION PROCEDURES
Follow the appropriate manufacturer's procedures when producing butt fusions with hydraulic equipment.
Review Joint Report generated by DataLoggerTM to confirm fusion success.
D. ELECTRO FUSION PROCEDURES
NOTE: See the Universal Control Box Manufacturer’s literature for fusion information. The manufacturer’s
literature must be adhered to insure acceptable fusions.
In the event that the supply voltage varies outside of the stated limits the fusion cycle will be interrupted. A
new cycle can be started after a ten-minute cool down period has been observed. The fusion system will
automatically adjust the duration of the cycle to compensate for the previously aborted attempt. A
maximum of three attempts may be tried. If the tapping tee has already been tapped, NO retries are
allowed.
E. REQUIREMENTS FOR HDPE FUSION TESTING
Applicants for testing will need to demonstrate a working knowledge of HDPE fusion and equipment
without any assistance. The test will be given as a whole. The Contractor will be required to complete
a minimum 4” butt fusion on a hand machine, a 6” butt fusion on a hydraulic machine with a Data
Logger using a McElroy DL5 or higher, a 4” electrofusion coupling, and a 4x8 electric fusion saddle.
Each fusion applicant must bring the following to the test:
x 4” pipe (DR specific), 6’ long for hand fusion using a McElroy Pit Bull 14 (City Staff Only)
x 6” pipe (DR specific), 6’ long for hydraulic fusion on a McElroy 28, 618 or Acrobat 180 fusion machine
(Contractor and City Staff)
x Minimum of 1 each 4” electrofusion coupling and 4x8 electrofusion saddle (recommend at least 2
each, per person tested)
x 3’ of 8” pipe (DR specific)
x Proper tools required to do the work (scraper cutter, lint free cotton towels, etc.)
x Isopropyl alcohol 95% or greater (99% preferred)
x A working contact or infrared pyrometer, and working generator to power the electrofusion box (with
fuel)
x A working reciprocating saw and blades to cut the pipe
x Extension cords and any other saws or cutters you plan to use on the job. Chainsaws are not
permitted.
x McElroy 2LC fusion machine up to 2” or McElroy Pit Bull 14 – note that irons must have stripper bars
and be clean and in good condition. Facer blades must be clean and in good condition in accordance
with the Manufacturer’s specifications. Any machine not meeting these standards will need to be
repaired by an authorized service center that is recognized by the manufacturer
x McElroy 28, 618 or Acrobat 180 fusion machine– must be clean and in good condition. Facer blades
must be clean and in good condition in accordance with the Manufacturer’s specifications. Any
machine not meeting these standards will need to be repaired by an authorized service center that is
recognized by the manufacturer.
x A working electrofusion box with supporting service maintenance history. Not a rental.
The City of Palo Alto’s electrofusion test is in place to test the operator and the equipment that will be used
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FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 8
on the job. All equipment must meet manufacturer’s standards per latest ASTM D2657. Contractor
shall note that the fusion testing process is a separate process from the City’s project review and
acceptance process.
It is the Contractor’s responsibility to ensure that all equipment is fueled prior to the test being
administered. All equipment must have a serial number or equipment number. Any missing tools or
equipment will result in no test being conducted, or a FAIL will be given. All materials should be what will
be used on the project of which the Contractor is being certified.
See Specification 2300 (Polyethylene Pipe Installation for Water, Gas and Wastewater) for additional
testing requirements.
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CITY OF PALO ALTO: HDPE Fusion Practical Test (Sample)
Applicants for fusion certification will be required to pass both a physical and written exam prior to
being certified.
Name:_______________________ Date:________________
Title:________________________ Company:____________
Individual should be tested on all procedures he/she is to be certified under. (Unmarked boxes constitute
failure in that type procedure).
□ ELECTRO FUSION COUPLINGS
□ 1. Pipe ends were cut square and even.
□ 2. Cleaned pipe ends inside and out.
□ 3. Measured and marked pipe ends.
□ 4. Scraped pipe ends.
□ 5. Took proper precautions to avoid contamination of pipe ends.
□ 6. Cleaned fitting and pipe ends with alcohol.
□ 7. Centered fitting between marks.
□ 8. Connected control box to proper 110 volt A.C. power source in correct sequence.
□ 9. Had thorough understanding of operation sequence and warning light functions.
□ 10. Noted time that FUSION START BUTTON was depressed.
□ 11. Marked time of day on pipe at end of fusion.
□ 12. Removed leads from fitting 30 seconds or longer after fusion was over.
□ 13. Allowed fitting to cool in secured position for recommended time.
□ ELECTRO FUSION TAPPING TEES
□ 1. Cleaned pipe around fusion zone.
□ 2. Scraped entire pipe surface that will fall under tee.
□ 3. Took proper precautions to avoid contamination of scraped pipe.
□ 4. Cleaned fitting and scraped area with alcohol.
□ 5. Placed tee on scraped area.
□ 6. Properly installed under-saddle/hold-down clamp.
□ 7. Connected control box to proper 110 volt A.C. power source in correct sequence.
□ 8. Had thorough understanding of operation sequence and warning light functions.
□ 9. Swiped fitting UPC with optical wand.
□ 10. Noted time that FUSION START BUTTON was depressed.
□ 11. Marked time of day on pipe at end of fusion.
□ 12. Removed leads from fitting 30 seconds or longer after fusion was over.
□ 13. Allowed fitting to cool in secured position for recommended time.
□ BUTT FUSION MANUAL (CITY STAFF ONLY)
□ 1. Pipe ends were faced properly to the facer stops.
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FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
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□ 2. Removed cuttings from interior of pipe.
□ 3. Aligned pipe ends for “high-low”, refaced if needed.
□ 4. Cleaned heater face and verified heating iron surface temperature with pyrometer.
□ 5. Observed recommended melt bead prior to timing.
□ 6. Observed recommended melt time.
□ 7. Maintained pressure on fusion during recommended cool down period.
□ 8. Allowed joint to cool in machine for recommended period.
□ 9. Knowledge of rough handling time.
□ BUTT FUSION HYDRAULIC
□ 1. Completed an inspection of equipment for cleanliness and proper operation.
□ 2. Cleaned pipe ends inside and out.
□ 3. Pipe ends were faced properly to the facer stops.
□ 4. Shavings and chips removed after facing pipe.
□ 5. Pipe ends brought together under facing pressure, no visual gaps observed.
□ 6. Aligned pipe ends for “high-low”, refaced if needed.
□ 7. Checked for pipe slippage at fusion pressure and pipe ends kept closed.
□ 8. Calculated drag pressure properly. Drag Pressure __________psi.
□ 9. Theoretical Fusion Pressure Calculated. Theoretical pressure __________psi.
□ DataLogger □Fusion Pressure Calculator
□ McCalc □ Formula
Observed gauge pressure (theoretical fusion pressure + drag) used to fuse the pipe
__________psi.
□ 10. Cleaned heater face and verified heating iron surface temperature with pyrometer.
□ 11. Recommended shift sequence followed.
□ 12. Bead size against the heater meet standard before heater removal.
□ 13. Inspected pipe interfacial area after heater removal.
□ 14. Removal of heater completed in allotted time.
□ 15. Completed cooling cycle time (under fusion pressure).
□ 16. Operator proficient with Data Logger setup and operation.
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JOINT EVALUATION
Visual Examination (During and after assembly. Compare to Photograph or sample of acceptable joint.)
Procedure/Joint Appearance
PROCEDURE
JOINT
APPEARANCE
ADDITIONAL
INSTRUCTION REQUIRED
IN PASS FAIL
BUTT FUSION (MANUAL) _____”
BUTT FUSION (HYDRAULIC) _____”
ELECTRO
COUPLING _____”
FUSION
TAPPING TEE _____”
□ DEFORMATION TEST ≤ 3” TENSILE TEST ≥ 4”
□ Specimen cut into test template or longitudinal straps. (Joint should be free of voids or unbonded areas
on surface.)
Joint Evaluation (Visual)(Deform joint by bending or tensile test)
PROCEDURE
JOINT
APPEARANCE
ADDITIONAL
INSTRUCTION REQUIRED
IN PASS FAIL
BUTT FUSION (MANUAL) _____”
BUTT FUSION (HYDRAULIC) _____”
ELECTRO
COUPLING _____”
FUSION
TAPPING TEE _____”
Certification obtained in the following utility (s)
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CITY OF PALO ALTO Section 2400 PAGE 12
□Water □Wastewater
RECOMMENDATION:
□ Retest Required.
□ Certification Card Issued/Date _______________________
□ Re-Certification Card Issued/Date ____________________
Certified in the following application(s):
□ Butt Fusion
□ Couplings
□ Tapping Tees
_________________________________________ __________________________
Employee Signature Date
______________________________ ______________________________ _____________
Evaluator Name and Title Evaluator Signature Date
70
FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 1
SECTION 2500
FUSION PROCEDURES AND CERTIFICATION (GAS)
Revised 02/26/20
TABLE OF CONTENTS
PAGE
SUBJECT NUMBER
Heat Fusion Tools 2
Manual Butt Fusion Procedure (City Staff Only) 4
Hydraulic Butt Fusion Procedure 5
Electro Fusion Procedure 6
Requirements for PE Fusion Testing 6
Polyethylene Gas Pipe Fusion Practical Test (Sample) 8
71
FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 2
CITY OF PALO ALTO: Polyethylene Gas Pipe Fusion Procedures
It is responsibility of a fuser to verify that polyethylene pipe and fittings are in conformance with
the specifications requirements and no older than 6 months from the date of manufacture to the
date of arrival to CPA.
A. HEAT FUSION TOOLS
1. BUTT FUSION
NOTE: The manufacturer’s operating instructions must be adhered to insure acceptable fusions.
a. Heating Iron
The heating irons are NOT EXPLOSION PROOF and shall not be used in any area with gas
present while still connected to a power source.
An electrically resistive coil in the heating iron maintains the temperature at a level sufficient for
fusion. The irons operate on 110 volts A.C. with power requirements ranging from 1200 to 1750
watts. Teflon coated faces are utilized on both sides of the iron. Extreme care must be exercised
to avoid scratching the faces; only lint free cloths should be used for cleaning. The faces are
either an integral part of the iron or are detachable and must be replaced when scratched. A dial
type thermometer is placed next to the handle. The iron temperature can be adjusted by
changing the calibration set screw.
b. Butt Fusion Machine
Machine shall be the hydraulic fusion machine with built-in hydraulic pipe lift to assist with the
pipe handling and incorporating centerline guidance system and DataLoggerTM compatible, and
capable of butt fusion of most fittings without special holders or removal of jaw. Contractor to
provide hydraulic McElroy butt fusion machine or approved equal.
c. Alignment Clamp Inserts
Sufficiently sized alignment clamps must be included with the butt fusion machine for the
diameter of pipe(s) to be fused.
d. Facer
1. Electrical facers must be used with the butt fusion machines. Facer shall have sharp properly
aligned blades. The electrical facers are NOT EXPLOSION PROOF and shall not be used in
any area with gas present.
2. ELECTRO FUSION
NOTE: The manufacturer’s operating instructions must be adhered to insure acceptable fusions. All
electrofusion boxes must be calibrated at intervals not exceeding 3 years, or more often if
manufacturer recommends accelerated calibration interval.
a. Universal Control Box
The Contractor shall provide a universal electrofusion control box, capable of storing a minimum
of 100 fusion records. All previous fusions must be completely cleared from the box memory prior
to arriving for testing.
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FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 3
b. Electric Generator
Contractor shall provide the necessary power supply to meet the power requirements as
specified by the manufacturer of the fusion equipment. Generator shall be in new condition and
have a minimum rated capacity of 5 kW for 8” and smaller and 10 KW for 10” and larger.
c. Barcode Wand or Hand-held Scanner
This device reads the uniform product code UPC sticker on the fitting.
d. Electrofusion Couplings
A resistant wire embedded in the coupling provides the energy required for fusion.
i. Alignment Clamps
Are required for 1" and larger diameter pipelines. These devices align and immobilize the
pipe ends and coupling during the fusion and cool down periods.
ii. Pipe Scrapers
Three types of scrapers are used to remove oxidation and contaminants from the outside
pipe wall prior to electro fusion coupling installation. Virax type or interior anchored pipe
scraper can be used on 1/2" CTS - 6" IPS sizes. Additionally, full encirclement Scrapers can
be used on 2" - 8" pipe sizes.
e. Tapping Tees
The tees also have a resistant wire coil that provides the energy for fusion. They require either a
back up under saddle or a ratchet operated clamp to fix the tee to the main during fusion. A
threaded cutter is included for tapping the main.
i. Service Line Alignment Clamp
When applying the service line to the outlet of a tapping tee an alignment clamp shall be
used to insure that the outlet and the service line are straight. This unit also immobilizes the
coupling during the fusion and cool down periods.
ii. Ratchet Clamp
All pipe sizes require the use of a hold down clamp or backing plate to secure the tapping tee
onto the main during fusion.
3. MISCELLANEOUS TOOLS
a. Pipe Cutters
i. "Plier" type cutters may be used for pipelines 1/2" CTS - 2" IPS in diameter.
ii. For 3” – 12” diameter pipe, guillotine style pipe cutter outfitted with a ratchet drive or power
driven designed to cut medium density polyethylene pipe may be used. A reciprocating saw
may be used to cut pipe, as long as all cleaning and pipe facing applications are performed.
b. Pyrometer
73
FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 4
The Contractor shall provide a pyrometer capable of testing the temperature of the heating iron,
while at fusion temperature, to an accuracy of 0.5% (r3qF). The fusion temperature of the
heating iron shall be verified prior to testing. A handheld display unit with infrared beam or
attached surface probe may be used.
B. MANUAL BUTT FUSION PROCEDURES (CITY STAFF ONLY)
1. Energize the heating iron. Once the heater has reached maximum temperature, generator cycles off,
check the thermometer for 425° ± 25°F.
At the start of each day, the reading of the dial thermometer shall be checked against the surface
temperature by use of the pyrometer and the heating iron calibration set screw adjusted accordingly
(manual machines only).
2. Install the proper size alignment clamp inserts if required.
3. Inspect the pipe and/or fitting ends and cut off any damaged or flattened portions.
4. Clean each pipe/fitting end with a clean lint free cloth and place the pipe in the alignment clamps.
Pipe ends should overlap the alignment clamps by approximately 1".
5. Place the manual or the motorized facer on the guide rods and bring the pipe ends in contact with it.
Turn the manual facer in the direction of the arrow or turn the motorized facing unit on and apply light
force on the carriage lever to advance the pipe ends. The motorized facer speed will increase when
the pipe has bottomed out.
6. Retract the carriage lever and remove the facer. Discard the strips of material from the pipe ends
taking care not to touch the clean surfaces. Check the discarded strips to ensure that a continuous
length from the entire diameter has been removed.
7. Check alignment of the pipe ends and adjust for high-low if necessary. If an adjustment is made or a
visible gap exists between the pipe ends, repeat the procedures from Step 4.
8. Wipe heater with a non-synthetic clean lint free cloth and place it on the guide rod(s) and bring the
pipe ends into contact with it. Maintain a light force on the carriage until a small melt bead forms
around the entire circumference of both pipe ends. Relax the force on the carriage but keep both
pipe ends in contact with the heater and start the melt time cycle. Refer to Table 1 for proper melt
times.
9. After the melt time has been observed snap the carriage back (open) and quickly remove the heater
being careful not to hit the melt.
10. Inspect the pipe ends for complete melt. Bring the pipe ends together quickly, DO NOT SLAM,
applying only enough pressure to form a double roll back bead. The proper bead thicknesses are
shown in Table 1. Over-pressuring the melt will cause the bead to overlap itself resulting in a
subquality fusion due to displacement of the melt to the OD and ID of the joint leaving a cold ring in
the center. Under pressuring can result in inadequate fusion due to insufficient contact pressure in
the melt area.
11. Maintain the pressure exerted on the fusion area for one minute for 1/2"-4" sizes and for three
minutes for 6". Relaxing the pressure prior to expiration of the cooling time can result in porous
fusion joints.
12. Allow the joint to cool for additional three to four minutes (see Table 1) prior to removal from the
alignment clamps. The pipe can now be handled with care. Complete cooling requires
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FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
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approximately thirty minutes.
13. Check the melt bead for uniformity and size. If the joint exhibits poor characteristics, determine the
cause, make the necessary corrections, cut out the suspect joint, and repeat the procedure from Step
4.
14. Clean the heater faces with a clean cotton cloth. DO NOT use synthetic cloths or metal implements.
TABLE 1: Manual Butt Fusion Parameters
Pipe Size
Melt Bead
Size
Heating Time
(seconds)
Hold Time
(seconds)
Cooling Time
(minutes)
1/2" CTS
1/16"
3-6
60
3
1" CTS
1/16"
5-9
60
3
2" IPS
1/16"-1/8"
15
60
4
3" IPS
1/8"
20
60
4
4" IPS
1/8"
20
60
4
6" IPS
3/16"
30
180
5
C. HYDRAULIC BUTT FUSION PROCEDURES
1. Energize the heating iron. Once the heater has reached maximum temperature, generator cycles off,
check the thermometer for 425° ± 25°F.
At the start of each day, the reading of the dial thermometer shall be checked against the surface
temperature by use of the pyrometer and the heating iron calibration set screw adjusted accordingly
(manual machines only).
2. Install the proper size alignment clamp inserts if required.
3. Inspect the pipe and/or fitting ends and cut off any damaged or flattened portions.
4. Clean each pipe/fitting end with a clean lint free cloth and place the pipe in the alignment clamps.
Pipe ends should overlap the alignment clamps by approximately 1".
5. Place the motorized facer on the guide rods and bring the pipe ends in contact with it. Turn on the
motorized facing unit and advance the pipe ends into the facing unit. The motorized facer speed will
increase when the pipe has bottomed out.
6. Retract the carriage and remove the facer. Discard the strips of material from the pipe ends taking
care not to touch the clean surfaces. Check the discarded strips to insure that a continuous length
from the entire diameter has been removed.
7. Check alignment of the pipe ends and adjust for high-low if necessary. If an adjustment is made or a
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FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 6
visible gap exists between the pipe ends, repeat the procedures from Step 4.
8. Wipe heater with a non-synthetic clean lint free cloth and place it on the guide rod(s) and bring the
pipe ends into contact with it. The carriage should be placed in heat soak until a small melt bead
forms around the entire circumference of both pipe ends. Refer to Table 1 for proper melt times.
9. After the melt time has been observed the carriage should be opened and quickly remove the heater
being careful not to hit the melt.
10. Inspect the pipe ends for complete melt. Bring the pipe ends together quickly until a double roll back
bead is formed. The proper bead thicknesses are shown in Table 1.
11. Maintain the pressure exerted on the fusion area until required.
12. Allow the joint to cool for additional three to four minutes (see Table 1) prior to removal from the
alignment clamps. The pipe can now be handled with care. Complete cooling requires
approximately thirty minutes.
13. Check the melt bead for uniformity and size. If the joint exhibits poor characteristics, determine the
cause, make the necessary corrections, cut out the suspect joint, and repeat the procedure from Step
4.
14. Clean the heater faces with a clean cotton cloth. DO NOT use synthetic cloths or metal implements.
D. ELECTRO FUSION PROCEDURES
NOTES: See the Universal Control Box Manufacturer’s literature for fusion information. The
manufacturer’s literature must be adhered to insure acceptable fusions.
In the event that the supply voltage varies outside of the stated limits the fusion cycle will be interrupted.
A new cycle can be started after a ten-minute cool down period has been observed. The fusion system
will automatically adjust the duration of the cycle to compensate for the previously aborted attempt. A
maximum of three attempts may be tried. If the tapping tee has already been tapped, NO retries are
allowed.
E. REQUIREMENTS FOR PE FUSION TESTING
Applicants for testing will need to demonstrate a working knowledge of Polyethylene pipe fusion
procedures and equipment without any assistance. The test will be given as a whole. The Contractor
will be required to complete a minimum 6” butt fusion on a hydraulic machine with a Data Logger
using a McElroy DL5 or higher, a 4” electrofusion coupling, and a 2”x6” electrofusion service tee
saddle. A 2” butt fusion on a hydraulic machine with a Data Logger using a McElroy DL5 or higher
may be required if 2” Polyethylene pipe will be installed.
Each fusion applicant must bring the following to the test:
x 2” pipe (DR 11), 6’ long and performed on a hydraulic fusion machine (if applicable)
x 6” pipe (DR 11.5), 6’ long and performed on a hydraulic fusion machine
x Minimum of 1 each 6” electrofusion coupling and 2”x6” electrofusion service tee saddle
(recommend at least 2 each, per person tested)
x Proper tools required to do the work (scraper cutter, lint free cloths, etc.)
x Isopropyl alcohol 95% or greater (99% preferred)
x A working contact or infrared pyrometer, and working generator to power the electrofusion box
(with fuel)
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FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
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x A working reciprocating saw and blades to cut the pipe
x Extension cords and any other saws or cutters you plan to use on the job. Chainsaws are not
permitted.
x For manual fusion only (City Staff) 2LC or up to 2” or PitBull 14 – irons must have stripper bars
and be clean and in good condition. Facer blades must be clean and in good condition in
accordance with the Manufacturer’s specifications. Any machine not meeting these standards will
need to be repaired by an authorized service center that is recognized by the manufacturer
x For hydraulic fusion only (Contractor and City Staff) 28, 618 or Acrobat 180 – irons must have
stripper bars and be clean and in good condition. Facer blades must be clean and in good
condition in accordance with the Manufacturer’s specifications. Any machine not meeting these
standards will need to be repaired by an authorized service center that is recognized by the
manufacturer.
x A calibrated and working electrofusion box. Not a rental.
The City of Palo Alto’s electrofusion test is in place to test the operator and the equipment that will be
used on the job. All equipment must meet manufacturer’s standards per ASTM F1055 and
F2620. Contractor shall note that the fusion testing process is a separate process from the City’s
project review and acceptance process.
It is the Contractor’s responsibility to ensure that all equipment is fueled prior to the test being
administered. All equipment must have a serial number or equipment number. Any missing tools
or equipment will result in no test being conducted, or a FAIL will be given. All equipment used for
Contractor certification, should be the same equipment used on the project.
See Specification 2300 (Polyethylene Pipe Installation for Water, Gas and Wastewater) for additional
testing requirements.
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CITY OF PALO ALTO: Polyethylene Gas Pipe Fusion Practical Test (Sample)
Applicants for fusion certification will be required to pass both a physical and written exam prior to
being certified.
Name:_______________________ Date:________________
Title:________________________ Company:____________
Individual should be tested on all procedures he/she is to be certified under. (Unmarked boxes constitute
failure in that type procedure).
□ ELECTRO FUSION COUPLINGS
□ 1. Pipe ends were cut square and even.
□ 2. Cleaned pipe ends inside and out.
□ 3. Measured and marked pipe ends.
□ 4. Scraped pipe ends.
□ 5. Took proper precautions to avoid contamination of pipe ends.
□ 6. Cleaned fitting and pipe ends with alcohol.
□ 7. Centered fitting between marks.
□ 8. Connected control box to proper 110 volt A.C. power source in correct sequence.
□ 9. Had thorough understanding of operation sequence and warning light functions.
□ 10. Noted time that FUSION START BUTTON was depressed.
□ 11. Marked time of day on pipe at end of fusion.
□ 12. Removed leads from fitting 30 seconds or longer after fusion was over.
□ 13. Allowed fitting to cool in secured position for recommended time.
□ ELECTRO FUSION TAPPING TEES
□ 1. Cleaned pipe around fusion zone.
□ 2. Scraped entire pipe surface that will fall under tee.
□ 3. Took proper precautions to avoid contamination of scraped pipe.
□ 4. Cleaned fitting and scraped area with alcohol.
□ 5. Placed tee on scraped area.
□ 6. Properly installed under-saddle/hold-down clamp.
□ 7. Connected control box to proper 110 volt A.C. power source in correct sequence.
□ 8. Had thorough understanding of operation sequence and warning light functions.
□ 9. Swiped fitting UPC with optical wand.
□ 10. Noted time that FUSION START BUTTON was depressed.
□ 11. Marked time of day on pipe at end of fusion.
□ 12. Removed leads from fitting 30 seconds or longer after fusion was over.
□ 13. Allowed fitting to cool in secured position for recommended time.
□ BUTT FUSION MANUAL (CITY STAFF)
□ 1. Pipe ends were faced properly to the facer stops.
□ 2. Removed cuttings from interior of pipe.
□ 3. Aligned pipe ends for “high-low”, refaced if needed.
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FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
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□ 4. Cleaned heater face and verified heating iron surface temperature with pyrometer.
□ 5. Observed recommended melt bead prior to timing.
□ 6. Observed recommended melt time.
□ 7. Maintained pressure on fusion during recommended cool down period.
□ 8. Allowed joint to cool in machine for recommended period.
□ 9. Knowledge of rough handling time.
□ BUTT FUSION HYDRAULIC
□ 1. Completed an inspection of equipment for cleanliness and proper operation.
□ 2. Cleaned pipe ends inside and out.
□ 3. Pipe ends were faced properly to the facer stops.
□ 4. Shavings and chips removed after facing pipe.
□ 5. Pipe ends brought together under facing pressure, no visual gaps observed.
□ 6. Aligned pipe ends for “high-low”, refaced if needed.
□ 7. Checked for pipe slippage at fusion pressure and pipe ends kept closed.
□ 8. Calculated drag pressure properly. Drag Pressure __________psi.
□ 9. Theoretical Fusion Pressure Calculated. Theoretical pressure __________psi.
□ DataLogger □Fusion Pressure Calculator
□ McCalc □ Formula
Observed gauge pressure (theoretical fusion pressure + drag) used to fuse the pipe
__________psi.
□ 10. Cleaned heater face and verified heating iron surface temperature with pyrometer.
□ 11. Recommended shift sequence followed.
□ 12. Bead size against the heater meet standard before heater removal.
□ 13. Inspected pipe interfacial area after heater removal.
□ 14. Removal of heater completed in allotted time.
□ 15. Completed cooling cycle time (under fusion pressure).
□ 16. Operator proficient with Data Logger setup and operation.
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JOINT EVALUATION
Visual Examination (During and after assembly. Compare to Photograph or sample of acceptable joint.)
Procedure/Joint Appearance
PROCEDURE
JOINT
APPEARANCE
ADDITIONAL
INSTRUCTION REQUIRED
IN PASS FAIL
BUTT FUSION (MANUAL) _____”
BUTT FUSION (HYDRAULIC) _____”
ELECTRO
COUPLING _____”
FUSION
TAPPING TEE _____”
□ DEFORMATION TEST ≤ 3” TENSITE TEST ≥ 4”
□ Specimen cut into test template or longitudinal straps. (Joint should be free of voids or unbonded areas
on surface.)
Joint Evaluation (Visual)(Deform joint by bending or tensile test)
PROCEDURE
JOINT
APPEARANCE
ADDITIONAL
INSTRUCTION REQUIRED
IN PASS FAIL
BUTT FUSION (MANUAL) _____”
BUTT FUSION (HYDRAULIC) _____”
ELECTRO
COUPLING _____”
FUSION
TAPPING TEE _____”
Certification obtained in the following utility (s)
□Gas
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FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
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RECOMMENDATION:
□ Retest Required.
□ Certification Card Issued/Date _______________________
□ Re-Certification Card Issued/Date ____________________
Certified in the following application(s):
□ Butt Fusion
□ Couplings
□ Tapping Tees
_________________________________________ __________________________
Employee Signature Date
______________________________ ______________________________ _____________
Evaluator Name and Title Evaluator Signature Date
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SECTION 2660
WATER DESIGN AND CONSTRUCTION STANDARDS
PART 1 – GENERAL
1.01 DESCRIPTION
Work Includes installation of high density polyethylene (HDPE) water mains, water and fire services,
fire hydrants, tracer wire, water valves and boxes, mechanical joint and/or flange adapters, all
appurtenances, and all related equipment and fittings in accordance with the requirements of the
Contract Documents.
1.02 RELATED WORK
Section 2200: Excavation, Backfill and Restoration
PART 2 – DESIGN STANDARDS
2.01 PIPE SIZE
A. Minimum size of new main:
The minimum size of new HDPE water main shall be 8” (I.D. = 6.963), SDR 11.
B. Minimum size of new service:
The minimum size of new HDPE water service shall be 2” (I.D. = 1.815), SDR 9.
C. Calculating Service Size:
The service size calculation must be based on the Hazen-Williams Formula to calculate the head
loss due to pipe friction.
2.02 COVER AND CLEARANCES
A. Minimum/Maximum Cover:
1. Water mains shall be installed with a minimum and maximum cover, as measured vertically
from the top of pipe to the top of pavement. For 8” HDPE, a minimum depth of 3-feet is
required, with a maximum of 4.5-feet. For 10” and larger HDPE, a minimum depth of 4-feet is
required, with a maximum of 5.5-feet. Upon approval of the engineer, exceptions may be
allowed if existing conditions do not allow for the required minimum and maximum depths to
be maintained.
2. Water services shall be installed with a minimum cover of 24”, as measured vertically from
the top of pipe to the top of pavement. The maximum depth of installation shall not exceed
30”.
B. Underground Clearances:
1. Sewer, Recycled Water and Storm Utility Separation: For parallel construction, the distance
between new water mains and sewer, recycled water and storm drain lines shall follow the
State Water Resources Control Board’s separation requirements. Separation distances shall
be measured from the nearest edge of the facilities. Water mains and non-potable fluid-
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 2
carrying pipelines shall not be installed in the same trench. In the event that the minimum
clearances cannot be achieved, the City and the State Water Resources Control Board will
need to approve the plans. Any changes due to field conditions during construction that
decreases the separation will need to be reapproved prior to installation.
2. Gas, Electric, and other Utility Structures: For all other utilities, unless otherwise specified, a
minimum of 12-inches vertically and 48- inches horizontally shall be maintained between the
pipe surface and other utility line or structures. In the event that it is not possible to maintain
the required minimum vertical clearance from other structures, the Contractor shall encase
the water main in steel pipe or concrete at the discretion of the engineer. If horizontal
separation is between 1-foot and 4-foot, review and approval by the engineer is required.
Horizontal separation less than 1’ is prohibited.
2.03 LOCATIONS
A. Water mains shall be located 7-feet off the lip of gutter/edge of pavement on the north or east
side of streets, if possible, unless otherwise specified on the Project Drawings.
B. Water services shall be installed perpendicular from the water main, in the shortest straight line
to the water meter.
C. The minimum distance between service taps shall be 24 inches.
D. Water meters and services shall be installed 5-feet minimum from trees, edge of driveway, and
the sanitary sewer house lateral.
E. Water meters 2” and smaller in size shall be installed in the public right-of-way. The meter
location and installation shall conform to the WGW Utility Standard Details.
F. Water meters larger than two inches in size shall be installed on the customer's property,
adjacent to the customer’s property line.
G. The meter location and installation shall conform to the WGW Utility Standard Details.
2.04 METER BYPASSES
Some customers, such as hospitals, schools, beauty shops, and factories with processes requiring
uninterrupted water service, shall have bypasses installed around the meter so that tests and repairs
can be carried out without inconvenience to either the customer or the utility.
2.05 AVAILABLE PRESSURE
The water pressures in the distribution system vary with elevations of the area served. During
average demand conditions, pressures range from 40 to 125 psi, with an average of approximately
50 psi. The lowest design pressure that should be used is 40 psi. However, the City does not
guarantee a specific water main pressure, during peak hour and/or emergency conditions, as certain
areas of the City are subject to inadequate pressures. The water pressure in Foothill, west of
highway 280, may be as high as 200 psi.
For the design of fire protection systems requirements and request of Fire Hydrant Flow Data, the
service designer must consult the Palo Alto Fire Prevention Bureau at the Development Center
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 3
located at 285 Hamilton Avenue, 1st Floor, Palo Alto, CA 94301, Phone (650) 617-3184. For an
estimate of static pressure at the water supply main, contact WGW Utilities Engineering Development
Services at (650) 566-4501.
2.06 VALVES
A. Main Valves:
All main line valves shall be installed per Section 4.01A.13 of this Specification. Four water
valves shall be installed at each water main intersection or cross, and three valves shall be
installed at each water main tee at the City’s right-of-way line projection at the intersection.
Valve spacing shall not exceed 500 LF unless approved by the City. See Figure 1 below. A 2”
HDPE bypass with 2” full port ball valve (NSF 61 listed) shall be installed around each 14” and
larger gate valve to facilitate operation of the valve (standard detail WD-14). For installation
requirements in contaminated areas see Section 2.10 of this Specification.
Where no permanent road features are available in the right-of-way, the valves shall be located
by a “blue” fiberglass utility marking post, offset 5-feet from the mains, and marked with a utility
decal with the words "WATER VALVE" on both sides of the marker.
Install four valves at Install three valves at
each water main intersection each water main tee
Figure 1.
B. Blowoffs And Air Release Valves:
Water mains shall not be designed as dead-end mains. Easements shall be provided to cross-
tie water mains in cul-de-sacs, and as required by the City. Blowoffs shall be provided at all low
points and as required by the City. Temporary blowoffs shall be provided as necessary to
pressure test and chlorinate new water main. Vacuum and air release valves shall be installed at
all summits in the water main, and as directed by the City.
C. Pressure Reducing Valves:
Pressure reducing valves (PRVs) are used in mountainous and hilly areas to control the
downstream pressure and protect the property owner’s plumbing from excessive pressure when
his building is located in the lower elevations of the pressure zone. These are installed by the
customer at the meter or at a suitable location in the customer’s plumbing system to permit
reduced pressure to the house fixtures. PRV’s must be installed to leave maximum pressure at
outside hydrants. It is customer’s responsibility to install and maintain all PRVs.
2.07 FIRE HYDRANTS
Fire hydrants shall be located no more than 500 feet apart in residential areas and no more than 300
feet apart in the downtown areas. Locations and usage shall comply with City of Palo Alto Utilities
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 4
Rule and Regulation 21.
2.08 ELEVATION OF THE CUSTOMER’S SYSTEM
Customers on hillsides or in high-rise buildings will be affected by the difference in elevation between
the utility’s water main and customer’s outlet. If the customer is at an elevation less than that of the
water main, then he can anticipate a higher pressure than that in the main, and conversely, the
homeowner at a higher elevation than the main will encounter lower water pressure. Multistory
buildings will often be too high to use the available main pressure, and pumping will be necessary. It
is the responsibility of the customer’s engineer to design the system from the meter outlet to
determine the pressure that will be available to meet their demand.
2.09 MAXIMUM VELOCITY OF FLOW
A. For water main: The maximum design flow velocity in any water main shall not exceed 7 feet per
second, based on the maximum calculated loads. Maximum distribution pipeline velocity for
maximum day demand plus fire flows shall not exceed 12 feet per second.
B. For water services: The maximum design flow velocity in any residential or commercial water
service shall not exceed 10 feet per second, based on the maximum calculated loads. Maximum
design flow velocity for dedicated fire services shall not exceed 12 feet per second, based on fire
flow demands.
2.10 INSTALLATION IN CONTAMINATED AREAS
For areas of known contamination or where contaminated soil is found the following materials must
be used:
A. Mains: Ductile iron water pipe (DIP) per Section 4.01A.2 of this Specification.
B. Gaskets: NBR or FKM gaskets, depending on the contamination type/levels. Submittals shall be
approved by the Engineer. Gasket lubricant shall be as specified by the pipe manufacturer.
C. Gate Valves: Gate valves per Section 4.01A.13 of this Specification.
D. Services: 2 CTS inch diameter, Type K copper tubing meeting ASTM B88 copper tubing
specification. If the existing service is not copper, the service shall be replaced with new copper
tubing. All services shall be replaced or reconnected in the original size, or 2” copper, whichever
is larger. Four inch and larger services shall be installed using DIP pipe. All services shall be
installed and/or reconnected in accordance with AWWA C800.
E. Service Saddle: Shall be Mueller BR2B series.
2.11 TEMPORARY WATER MAIN BYPASS SYSTEM (REPLACE-IN-PLACE METHOD)
In order to eliminate water service disruptions to customers who require 24 hour a day service, a
temporary water main bypass system will be required. Temporary water main shall be a minimum of
2-inch diameter unless otherwise specified. Temporary water main is required to be disinfected,
flushed, and sampled prior to any service connections being made. The temporary water main shall
also be tested at static main pressure for a period of 2-hours.
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
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Bypass piping required for an extended period of time, if directed by the Engineer, shall be buried or
covered by granular material ramps where the pipe crosses bike trails, sidewalks, driveways, roads,
pedestrian crossings, etc. Products used shall be manufactured from water distribution piping and
couplings and shall be NSF approved for potable water use.
2.12 NEW DEVELOPMENTS
The applicant's engineer shall provide the required plans submittals (see list in 2.12.B) including the
estimated water demand needed for the review. City of Palo Alto has developed a Domestic Water
System Hydraulic Model of the entire water supply and distribution system. This model will be
utilized by City of Palo Alto Utilities staff and/or a City consultant to verify the size of the domestic
water system facilities required for each development at the developers cost. When the City deems it
necessary, the Developer will be required to provide a water model of the on-site development,
showing that the development can operate under the provided pressure and load parameters
identified by the City.
A. The recommendations for the new development water system improvements shall include a cost
estimate and suggested design criteria. Development Services staff reserves the right to
determine the system design criteria for each water system based upon conditions that may exist
for a particular location, anticipated level of development, planned use or other criteria.
B. Plan Check Submittal Requirements: All plans or inquiries should be submitted to Development
Services of the engineering department for routing to the appropriate staff for review.
1. The developer/engineer must submit a preliminary utility plan showing the proposed location
of the services (domestic, irrigation, fire service), meters, and backflow devices.
2. Expected average day, maximum day, and peak hour water demand in gallons per minute
(gpm) for domestic and irrigation of the entire development. All assumptions must be
explicitly stated and properly documented.
3. Minimum expected fire flows in gpm required by the Fire Department.
4. Documentation or written correspondence with conditions of approval from Palo Alto Fire
Marshall indicating the development’s fire flow requirements stated in gpm, duration in hours
and residual pressure in psi.
5. Information to determine number of equivalent dwelling units:
a. Raw acreage of the development
b. Number and type of residential units
c. Building square feet (SF) of commercial, retail, industrial, hotel, etc.
6. Changes to the development (units, land use, project or construction phasing, etc...) may
require the City hydraulic model be re-run at the Developers expense.
7. The service design load shall be the total present (and additional future) water demand as
presented on the Utilities Application - Load Sheet.
8. Hydraulic modeling analysis comments are for plan check purposes only. The ultimate
design responsibility resides with the developer’s Engineer-of-Record for the Project.
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
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2.13 IRRIGATION METERS
Water service for all new and rehabilitated industrial, commercial, and institutional landscaping, and
new and rehabilitated multi-family common areas, requires a permit and/or review by the City and
shall be provided by a separate irrigation meter. This meter shall be designed as an irrigation account
and no other utilities will be billed on such accounts. The customer shall pay for the additional service
according to Utility Rate Schedule W-5.
PART 3 – REGULATORY STANDARDS
3.01 CROSS CONNECTION CONTROL
Cross Connection Control shall be installed per City of Palo Alto Utility Rule and Regulation 21
Section E "Water System Protection” in the SPECIAL WATER UTILITY REGULATION, the revised
California Administrative Code (Title 17, Sections 7583 through 7605), and WGW Utility Standards
Details WD-11 through WD-12D. For further questions contact the Utilities Cross Connection
Inspector at 650-496-6972.
A. Type of Protection Required:
The type of protection provided to prevent backflow into the public water supply will directly
correlate with the degree of hazard that exists on the consumer's premises, as determined by the
Cross-Connection Control Officer. In locations where the water service may not be interrupted
during normal working hours, two parallel backflow preventer assemblies shall be installed
(Reference: California Administrative Code, Title 17, Section 7604).
B. Testing and Maintenance of Backflow Preventers:
The Cross-Connection Control Officer will ensure that adequate maintenance and periodic
testing is provided. Backflow preventers will be tested by a certified tester. Backflow preventers
will be tested at least annually or more frequently if determined to be necessary by the Cross-
Connection Control Officer. When a backflow preventer is found to be defective, it shall be
repaired or replaced within 30 calendar days. Backflow preventers will be tested immediately
after installation, relocation, or repair prior to being placed into service. The Cross-Connection
Control Officer will notify the water user when testing is needed. Reports of testing and
maintenance will be maintained by the City of Palo Alto for a minimum of three years.
C. Parallel Reduced Pressure Principle Assemblies:
Parallel reduced pressure principle assemblies shall be installed at all locations where the water
cannot be interrupted during normal working hours. Only backflow assemblies approved for the
State of California by USC Foundation for Cross-Connection Control and Hydraulic Research
may be used.
PART 4 - MATERIALS
4.01 WATER DISTRIBUTION SYSTEM MATERIALS
“Wetted surfaces” of all materials, piping, or plumbing fixtures intended for conveying or dispensing
potable water, supplied under these specifications, must contain less than 0.25% lead by weight in
compliance with AB 1953.
A. Polyethylene (HDPE) Pipe and Fittings:
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 7
1. Pipe: All potable water polyethylene pipe supplied under this Specification shall be High
Density Polyethylene Pipe (HDPE) PE 4710 with IPS dimensions conforming to the latest
edition of ANSI/AWWA C901 and C906 and ANSI/NSF Standard 61. Resin used in the
extrusion of water polyethylene pipe shall conform to the latest edition of the ASTM D 3350
Cell classification 445574C, or 445574E, with the specifications stated herein, and shall have
an oxidative resistance category of CC3.
a. All water main pipes shall be black with four (4) equally spaced, single longitudinal blue
stripes. Solid blue pipe may be used, but require prior approval. All water service pipes
shall be black with four (4) equally spaced, single longitudinal blue stripes. Solid blue
pipe may be used, but require prior approval. Both main and service piping shall have
AWWA specification stamp embedment or permanent blue-line print.
b. PENT test values of 2,000 hours min.
c. Pipe dimensions and tolerances: The outside diameter and wall thickness shall be within
the limits specified in Table 1.
Approved Manufacturers: The City of Palo Alto approved PE pipe manufacturer is CP CHEM
Performance Pipe, CSR Poly Pipe Industries, WL Plastics, JM Eagle. Any other PE pipe
manufacturer must receive prior approval.
Table 1: Dimensional Standards for IPS 4710 High Density Polyethylene Pipe
Nominal
IPS Size
Actual
Outside Diameter
(inches)
Minimum
Wall Thickness
(inches)
Average
Inside Diameter
(inches)
Standard Dimension Ratio
(SDR)
(unitless)
2" IPS 2.375 0.264 1.815 9
4" IPS 4.50 0.409 3.633 11
6" IPS 6.625 0.602 5.349 11
8" IPS 8.625 0.784 6.963 11
10" IPS 10.750 0.977 8.679 11
12" IPS 12.750 1.159 10.293 11
14" IPS 14.00 1.273 11.301 11
16" IPS 16.00 1.455 12.915 11
18” IPS 18.00 1.636 14.532 11
2. Fittings: All potable water polyethylene fittings supplied under this Specification shall be high
density 4710 polyethylene manufactured by the injection molding process, pressure class
200 or greater, and conform to the latest edition of ANSI/AWWA C901 and C906 and
ANSI/NSF Standard 61. Fabricated fittings may be installed with prior approval from the City
Engineer. Resin used in the molding shall conform to the latest addition of the ASTM D 3350
Cell classification 445574C (HDPE 4710) with the specifications stated herein.
a. All fittings shall have the AWWA specification stamp embedment or permanent line print.
All fittings shall be pressure class 200 or greater. Additional pipe thickness required for
saddle fusion fittings and other fittings to reach pressure class 200 shall be on the
outside of the pipe so flow is not constricted.
b. Approved Manufacturers: The City of Palo Alto approved PE pipe manufacturers are
CP CHEM Performance Pipe and Integrity Fusion Products Inc. Any other PE fitting
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 8
manufacturer such as CSR Poly Pipe Industries, Central Plastics/Georg Fischer, ISCO,
or equal must receive prior approval.
B. Ductile Iron (DI) Pipe and Fittings:
Upon approval of the Engineer, DI pipe and fittings will be accepted to facilitate water main tie-ins
and valve replacement, or at locations where HDPE cannot be used. For material requirements
in contaminated areas, refer to ‘Installation in Contaminated Areas’ in this Section.
All DI water pipe shall be Class 52 push-on type, in standard lengths to conform to ANSI/AWWA
C151/A21.51, ANSI/AWWA C111/A21.21 and ANSI/AWWA C150/A21.50. DI water pipe shall be
asphalt coated in accordance with ANSI/AWWA C151/A21.51 and shall be lined with cement
mortar lining of 1/16-inch minimum thickness, conforming to ANSI/AWWA C104/A21.4.
Mechanical joint fittings, joint restraints, shall be ductile iron Class 350, and shall be produced in
strict accordance with ANSI/AWWA C104/A21.4, ANSI/AWWA C153/A21.53 and shall conform
to details and dimensions published therein. Mechanical joint offsets shall conform to
ANSI/AWWA C110-82 and offset joints shall conform to ANSI/AWWA C111/A21.11. Push-on
joint ductile iron and cast iron fittings shall be in strict accordance with all applicable terms and
provisions of ANSI/AWWA C110/A21.10 and ANSI/AWWA C153. Joints shall be in accordance
with ANSI/AWWA C111/A21.11.
All DI pipe and fittings shall be encased in blue polyethylene tubing, 8 mil thick minimum, in
accordance with ANSI/AWWA C105/A21.5.
C. Polyvinyl Chloride (PVC) Pipe (DI Fittings):
Upon approval of the Engineer, PVC pipe and ductile iron fittings will be accepted to facilitate
water main tie-ins and valve replacement.
All PVC pipe supplied shall be class 200 meeting the requirements of ANSI/AWWA C900. PVC
pipe shall be no older than 1 year from the date of manufacture to the date of shipment to CPA,
provided the pipe is stored indoors in suitable containers; otherwise the pipe shall be no older
than 6 months from date of manufacture to date of shipment to CPA.
Mechanical joint fittings, joint restraints, for PVC pipe shall be ductile iron in accordance with
ANSI/AWWA C153/A21.53 and ANSI/AWWA C111/A21.11 with a rated working pressure of 350
psi. All tees, crosses, and elbows used with PVC pipe shall have mechanical joint ends.
Reducers shall have mechanical joint by mechanical joint (MJxMJ) ends. All ductile iron fittings
shall have an asphaltic coating in accordance with ANSI/AWWA C153/A21.53 and shall be
cement lined and seal coated with an asphaltic material in accordance with ANSI/AWWA
C104/A21.4. Mechanical joint ductile iron fittings shall be in accordance with ANSI/AWWA
C110/A21.10 and joints shall be in accordance with ANSI/AWWA C111/A21.11.
Joining standard lengths of PVC pipe shall be with bell ends consisting of an integral wall section
with a locked-in solid cross section elastomeric ring which meets the requirements of ASTM
F477 or couplings supplied by the manufacturer meeting the requirements of AWWA C900.
Additional Outside Agency Approvals: All PVC fittings for use with AWWA C900 pipe shall have
the approval of Factory Mutual (FM) and be listed by Underwriters Laboratories, Inc. (UL).
D. Main Tapping Hardware: All hardware must be ANSI/NSF 61 listed.
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
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1. Tapping Sleeve
a. HDPE Main: For HDPE main connections, saddle shall be HDPE 4710, class 200
electrofusion branch saddle (IPS to IPS), NSF 61 listed and meet or exceed applicable
ANSI/AWWA requirements manufactured by Georg Fischer Central Plastics, or
approved equal. The fittings shall be provided with bottom underclamps or installed
using a loading tool as specified by manufacturer’s installation procedure.
b. Non-HDPE Main: All tapping sleeves shall be epoxy coated with 304 stainless steel
washers, nuts and bolts. Tapping sleeves shall be as follows for Non-HDPE main
connections:
i. CIP/DIP/PVC: Tapping sleeve shall be JCM 6432 all 316 stainless steel, or approved
equal.
ii. ACP: Tapping sleeve shall be JCM 6432 all 316 stainless steel, or approved equal.
iii. CCP: Tapping sleeve shall be JCM 415, or approved equal.
2. Tapping Valves: Tapping valves shall be Mueller A-2361 class 250 ductile iron resilient
wedge gate valve with flange inlets and outlets, EPDM disc and O-rings, and be supplied
with 316 stainless steel washers, nuts and bolts.
E. Main Joining Hardware: All hardware must be ANSI/NSF 61 listed.
1. Electrofusion Couplings (HDPE to HDPE): Electrofusion couplings shall be Georg Fischer
Central Plastics, Integrity IntegriFuse, or approved equal for HDPE 4710, IPS DR 11 (4” and
greater) and DR 9 (2”), Class 200 or greater, and ANSI/NSF 61 listed. HDPE pipe to HDPE
pipe shall be joined by butt or electro fusion.
2. Mechanical Joint (MJ) HDPE Adapter Kit (HDPE to PVC/DIP): Mechanical Joint (MJ) adapter
kit shall be pressure class 200 or greater, designed for fusion to HDPE pipe, and mechanical
connection to DIP or PVC pipe. Glands, material assembly and bolting shall be in
accordance with ANSI A21.11 (AWWA C111); full face rubber gasket shall be included in the
kit. The MJ adapter connection shall provide a fully self-restrained joint and shall not require
additional restraint. MJ adapters shall have AWWA C110 heavy-weight metal glands and
stainless steel stiffeners.
3. Mechanical Couplings: All mechanical couplings (parts) shall be NSF 61 listed and pressure
class 200 or greater and in accordance with ANSI/AWWA C153/A21.53. HDPE pipe shall
have a pipe stiffener at each mechanical coupling joint. Outside pipe diameter shall be
confirmed in the field prior to ordering mechanical couplings.
a. HDPE to HDPE: Mechanical coupling for joining HDPE when a complete water shutdown
is not possible, and electrofusion couplings cannot be used, shall be a Romac Industries
Alpha Restrained Joint, EBAA Iron Mega-Coupling Series 3800, or approved equal.
b. HDPE to ACP (asbestos cement pipe): Mechanical couplings shall be Smith & Blair 462
Quantum Coupling, Romac Macro HP, EBAA Iron Mega-Coupling Series 3800, or
approved equal, meeting the following minimum requirements:
i. Sleeve: Ductile Iron ASTM A-536 designed for high strength/weight ratio. Ends shall
have smooth inside taper for uniform gasket seating.
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
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ii. Gaskets: Nitrile (Buna N)
iii. Follower Flanges: Ductile Iron ASTM A-536 designed for high strength/weight ratio.
Thickness determined by coupling size.
iv. Bolts & Nuts: 304 Stainless.
v. Finish: Fusion bonded epoxy coating in accordance with AWWA C213.
c. HDPE to CIP (cast iron pipe) or DIP (ductile iron pipe): Mechanical coupling shall be
Krausz Hymax Grip, Smith & Blair 462 Quantum Coupling, Romac Macro HP, EBAA Iron
Mega-Coupling Series 3800, or approved equal.
d. HDPE to PVC (polyvinyl chloride pipe): Mechanical coupling shall be Smith & Blair 462
Quantum Coupling, EBAA Iron Mega-Coupling Series 3800, or approved equal. HDPE
pipe shall be restrained by electrofusion flex restraints, and PVC pipe shall be restrained
using a tapered gripping ring.
e. CCP to DIP or other pipe: Mechanical coupling or coupling adaptor shall comply with
AWWA C219. Confirm the thickness of the steel cylinder pipe. For pipe less than ¼”
steel cylinder thickness use adaptors with a welded buttstrap. Follow manufacturer’s
recommendations for both couplings and adaptors. The coupling or adaptor shall be
Romac 400 series or approved equal.
4. Joint Restraints: All joint restraints shall be EBAA IRON 2000PV for PVC pipe and EBAA
IRON MEGALUG 1100 series for ductile iron pipe, or approved equal.
5. Mechanical Joint Bolts: Bolts for mechanical joint glands shall be Central Steel Services, Inc.
Corten T-Bolts, or approved equal, and shall be high strength, low alloy steel bolts only,
meeting the requirements of ANSI/AWWA C111/A 21.11 for rubber gasket joints for cast iron
or ductile iron pipe and fittings.
6. HDPE to Flange Connection: HDPE flange adapter shall be pressure class 200 or greater
and used to join HDPE pipe to an existing flange or gate valve. A backup ring for flange
adapter shall be pressure class 200 or greater and stainless. HDPE flange adapter shall
meet requirements specified in Subsection 7 and 8 for bolts, nuts and gaskets.
a. .
7. Bolts and Nuts For Flanged Joints: Bolting for buried flanged joints shall be Type 304
stainless steel, Grade B8 Hex Head bolts with Grade B8M Hex Head nuts, and shall comply
with all requirements of ASTM A193 and A194, respectively. Nuts shall be 304 stainless
steel.
8. Gaskets for Flanged Joints: Gaskets for flanged joints shall be 1/8” full face gasket designed
to be used with water system, conforming to AWWA C207 and NSF 61 standards. Gasket
shall be US Pipe Full Face Flange-Type gasket. Gaskets by other manufacturers need
approval by the Engineer. For gasket installation requirements in contaminated areas, see
Section 2.10 of this Specification.
9. Flexible Restraint Devices: Electrofusion HDPE pipe flex restraint device, encased in
concrete, shall be attached to HDPE pipe near all transition connections to prevent pull out of
HDPE pipe and/or movement of existing pipe. Flex restraint device shall be ISCO Georg
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
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Fischer Central Plastics or approved equal, designed for installation after a pipe is in place,
and be rated at min. 7000 lbs of force per fitting. Resin used to make this fitting shall meet
the requirements of ASTM 3350 with a cell classification of 345464C.
The electrofusion HDPE pipe flex restraints shall be installed in accordance with
manufacturer’s recommendations. Approximate Poisson effect pull force (Ib.), calculated per
AWWA M55 manual, for selected sizes of ANSI/AWWA C906 pipe operated at full rated
pressure, plus maximum allowable occasional surge pressure as follows:
Pipe size
(in.)
Approximate Pull Force
(lb)
Calculated Number of Flex
Restraints (each)
6 7,553 2
8 13,428 2
10 20,981 3
12 30,213 5
14 41,124 6
16 53,712 8
The Thrust Block Table and Valve Tie-Back Detail (Standard Details WD-13 and WD-18)
shall be used to size concrete encasement.
F. Service Hardware and Appurtenances: All hardware must be ANSI/NSF 61 listed.
1. HDPE Water Main Connection
a. HDPE Service: Service saddle shall be electrofusion IPS, HDPE 4710, Class 200
Electrofusion Branch Saddle manufactured by Georg Fischer Central Plastics, SA
Branch Saddle manufactured by Friatec, IntegriFuse manufactured by Integrity, or
approved equal. The fitting shall be NSF Standard 61 listed and meet or exceed
ANSI/AWWA applicable requirements. Pneumatic top-loading tool is required for proper
installation. Alternate installation methods may be used with prior approval from the City
Engineer.
b. Ball Valve (HDPE Service): Ball valve shall be 2” IPS DR 9, HDPE 4710 Class 200 Poly-
Water Valve manufactured by Polyvalve , or approved equal.
c. Copper Service: Service Saddle shall be electrofusion IPS, HDPE 4710, Class 200
Electrofusion Branch Saddle manufactured by Georg Fischer Central Plastics, VA
Branch Saddle manufactured by Friatec, IntegriFuse manufactured by Integrity, or
approved equal, with brass 360 Alloy outlets and Stainless 304 compression rings. The
fittings shall be NSF Standard 61 listed and meet or exceed ANSI/AWWA applicable
requirements. Pneumatic top-loading tool is required for proper installation. Alternate
installation methods may be used with prior approval from the City Engineer. The fittings’
outlets shall be designed for AWWA straight iron pipe thread.
d. Flare Nut Transition (Copper Service): Flare nut transition shall be Poly–Cam Series 914
female swivel flare nut, lead free, transition designed for connecting 2” IPS HDPE 4710
potable water services directly to Mueller angle meter stops H-14255N (1” and smaller)
or H-24277N (1-1/2” and larger), and 2” Mueller corporation stops B-25025N, or
approved equal.
The HDPE portion of the transition fitting shall be HDPE 4710 SDR 9, IPS size
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
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conforming to the latest edition of ANSI/AWWA C906, and have legible marking
indicating word “Water”, type of material (HDPE 4710), cell classification 445574C,
ANSI/AWWA C906, the manufacturer’s name or trademark, IPS size, OD, SDR, resin
supplier identification, and year of manufacture. All flare nut transition fittings shall
conform to NSF 61 standards.
e. Corporation Stops (Copper Service): Corporation Stops for connection to non-HDPE
mains shall be Mueller B-25000N or AY McDonald 74701B with AWWA taper thread and
copper flare straight connection outlets, or approved equal.
f. Three Part Unions (Copper Service): Three part unions shall be Mueller H-15400 with
copper flare nut on both ends, or approved equal.
2. Non-HDPE Water Main Connection (DIP, ACP, or PVC C-900 main/copper services):
Services Saddle shall be Class 200 NSF 61 listed Mueller BR2B bronze series with double
strap, or approved equal.
3. Angle Meter Stop: Angle meter stop shall be AY McDonald 74602B (FLR x Meter) for 1” and
smaller services and AY McDonald 74602B (FLR x Oval Flange) for 1-1/2” and 2” services,
or approved equal.
4. Ball Straight Meter Valve: Ball straight meter valve shall be Mueller B-20287N, or approved
equal.
5. Meter Boxes: Meter boxes shall be supplied by the Contractor when box replacement is
required or a new service is installed. The boxes shall be the following sizes:
Armorcast 11” x 21” x 12” Polymer Concrete Box (Part No. A6000492), Cover (Part No.
A6000489T-H7), Assembly with Drop-In Lid (Part No. A6000487T) and Plug (Part No.
A60000H7-PLUG-CPA)for 5/8”, 3/4" or 1” meters (Box Assembly Part No.
A6000492TACPA).
Armorcast 17” x 30” x 12” Polymer Concrete Box (Part No. A6001640PCX12), Cover (Part
No. A6001947TDZ), Assembly with Drop-In Lid (Part No. A6000482T-H7) and Plug (Part No.
A60000H7-PLUG-CPA) for 5/8” meters with 3/4" double headers (Box Assembly Part No.
A6001640TAPCX12CPA).
Armorcast 24” x 36” x 12” Polymer Concrete Box (Part No. A6001974PCX12), Cover (Part
No. A6001975TDZ), Assembly with Drop-In Lid (Part No. A6000482T-H7), and Plug (Part
No. A60000H7-PLUG-CPA) for 1” meters with 1” double headers (Box Assembly Part No.
A6001974TAPCX12CPA).
Armorcast 30” x 48” x 18” Polymer Concrete Box (Part No. A6001430PCX18), two (2)
Covers (Part No. A6001470TDZ) with two (2) Drop-In Lids (Part No. A6000482T-H7) and two
(2) Plugs (Part No. A60000H7-PLUG-CPA) for 1” quadruple headers and 1-1/2” and 2”
double and triple headers (Box Assembly Part No. A6001430TAPCX18CPA).
Armorcast 48”x96”x48” Polymer Concrete Vault with three (3) piece cover and two plugs for
4” and 6” water meter sets with 2” by-pass, and where combination fire/domestic water
services are installed (Box Assembly Part No. A6001449TAPCAX48CPA. Oldcastle
Precast/Christy B48 Box with two (2) self-closing, reading lids may also be used, as needed,
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 13
if approved by the Engineer.
Box assemblies include box, covers, reading lids, and plugs. Box and lid shall have a
minimum 20K rating (Tier 22) for all applications. Meter boxes shall not be installed in driving
lanes of public or private streets. Lids shall have “Water” marked on them and magnet
imbedded in cover.
All new water meter boxes shall be installed at standard depth (water meters shall be
installed at a depth of 10” from existing grade to the center of the meter per City standard
details). No additional extensions will be allowed to accommodate existing deep meters. If a
meter is found to be deeper than the standard 10”, Contractor will be required to raise the
meter to the standard depth of 10”.
G. Fire Hydrant Assemblies: Fire Hydrant assemblies shall use wet barrel type hydrants meeting
AWWA C503 standards. The fire hydrant assemblies shall be constructed using the following
materials:
1. Hydrants: Hydrants shall be AVK Series 24 Wet Barrel Hydrant in residential, commercial,
and heavy industrial areas. Any other hydrant manufacturer such as Clow or equal must
receive prior approval. AVK Series 24 Wet Barrel Hydrant shall be supplied with two (2) 2-
1/2” and one (1) 4-1/2” outlets conforming to AWWA C503, and shall be painted Safety
Yellow.
2. Hydrant Risers: Hydrant Risers shall be AVK Series 24/88X Flowguard II Hydrant Check
Valve conforming to the latest edition of ANSI C110/A21.10 standards and AWWA C503,
and as shown on WGW Utility Standards detail drawing WD-15.
3. Hydrant Bury: Hydrant Bury shall be 6” mechanical joint ductile iron conforming to the latest
edition of ANSI C110/A21.10 standards and AWWA C503, and as shown on WGW Utility
Standards detail drawing WD-15.
4. Hydrant Valves Locations: Hydrant valves shall be placed as close as practical to the water
main. For information on hydrant valves, see Section 2.01A.8 of this Specification.
5. Hydrant Valve Boxes: Hydrant Valve Boxes shall be Oldcastle Precast/Christy G05TBox
Traffic Valve Box with G05CT non-locking type metal traffic lid marked “Water”. Valve box
risers shall be solid 8” C-900 PVC pipe (Pressure Class 200) as shown on WGW Utility
Standard Detail WD-19.
H. Gate Valves (Hydrants and Mains):
1. 12” or Smaller (Installed with New HDPE Main): Gate valves 12” or smaller that are installed
on HDPE pipe shall be 250 psi, ductile iron ASTM A536 body, resilient-seated, tight closure
gate valves with non-rising stems, and have IPS HDPE 4710 DR 11 polyethylene pipe ends.
The valve shall be NSF 61 listed and meet or exceed AWWA C515 applicable requirements.
All gate valves shall have protective interior/exterior electrostatically applied fusion bonded
epoxy-resin coating in accordance with AWWA C550 requirements, stainless steel A2-Grade
304 bonnet and stuffing box bolts, and shall open counter clockwise. All gate valves shall be
American AVK 66/EEN (PE x PE), or approved equal.
2. 12” or smaller (Installed on Existing Non-HDPE Main): Gate valves 12” or smaller that are
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 14
installed on non-HDPE pipe shall be 250 psi, ductile iron ASTM A536 body, resilient wedge
gate valves with four point wedging mechanism, EPDM discs and O-rings, and non-rising
stems. The valve shall be NSF 61 listed and meet or exceed AWWA C515 applicable
requirements. All gate valves shall have protective interior/exterior fusion epoxy coating in
accordance with AWWA C550 requirements, and shall open counter clockwise. All bonnet
and stuffing box bolts shall be stainless steel 316. Valves shall have flange joint ends (FL x
FL), mechanical joint ends (MJ x MJ), or both flange and mechanical joint ends (FL x MJ).
Joints shall be in accordance with ANSI/AWWA C110/A21.10 (FL) and ANSW/AWWA C111
(MJ) requirements, as applicable. All gate valves shall be Mueller A-2361 Series, or
approved equal.
3. 14” or Larger: Gate valves 14” or larger shall be 250 psi, ductile iron ASTM A536 body,
resilient wedge gate valves with four-point wedging mechanism, EPDM discs and O-rings,
and non-rising stems. The valve shall be NSF 61 listed and meet or exceed AWWA C515
applicable requirements. All gate valves shall have protective interior/exterior fusion epoxy
coating in accordance with AWWA C550 requirements, and shall open counter clockwise. All
bonnet and stuffing box bolts shall be stainless steel 316. Valves shall have flange joint ends
(FL x FL), mechanical joint ends (MJ x MJ), or both flange and mechanical joint ends (FL x
MJ). Joints shall be in accordance with ANSI/AWWA C110/A21.10 (FL) and ANSW/AWWA
C111 (MJ) requirements, as applicable. All gate valves shall be Mueller A-2361 Series, or
approved equal.
I. Butterfly Valves (Transmission Mains):
Butterfly valves shall 250 psi rated, with ductile iron body conforming with ASTM 536 standards.
The valve shall be NSF 61 certified and shall meet requirements of ANSI/AWWA C504 Standard
Class 250B. The valve shall have ductile iron disc conforming with ASTM 536 standards. The
valve shall have seat-in-body design and nonmetallic bearings. All butterfly valves shall be
coated in accordance with AWWA C550 and C504 standards. All valve hardware shall be 304
stainless steel. Butterfly valves shall have a 2” bypass per Standard Detail WD-14. All butterfly
valves shall be Mueller, Lineseal Series or approved equal.
J. Valve Stem Extensions: Valve stem extensions shall be fusion coated and furnished with an
AWWA brass wrench; top of AWWA brass wrench nut not to exceed two (2) feet below finished
grade. The valve stem extension shall have a six inch (6”) diameter, ¼-inch thick, fusion-coated
black iron guide plate welded six inches (6”) below the AWWA brass wrench nut. Stem
extensions are to be installed on valves four (4) feet and greater in depth.
K. Valve Boxes: Valve boxes shall be Oldcastle Precast/Christy G05TBox Traffic Valve Box with
G05CT non-locking type metal traffic lid marked “Water”. Valve box risers shall be corrugated 8”
HDPE (smooth inner pipe). The riser outside diameter shall be between 9.0” to 9.4” and closely
match the valve box inside diameter at the point of insertion. See WGW Utility Standard Detail
WD-14.
L. Air Release and Air/Vacuum Valves:
1. Air Release Valves: Air release valves shall be APCO, Crispin-Multiplex Mfg. Co., or
approved equal, and shall conform to the latest edition of AWWA C512. For 8” through 12”
HDPE mains, air valve assemblies shall be a minimum of 1”, and for 14” and larger HDPE
mains, air valves assemblies shall be a minimum of 2”. All assemblies shall have stainless
steel floats.
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
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2. Air/Vacuum Valves: Air/Vacuum valves shall be APCO, Crispin-Multiplex Mfg. Co., or
approved equal, and shall conform to the latest edition of AWWA C512. For up to 10” HDPE
mains, air/vacuum valve assemblies shall be a minimum of 1”, and for 12” and larger HDPE
mains, air/vacuum assemblies shall be a minimum of 2”. All assemblies shall have stainless
steel floats. Air Release/Vacuum valve vents shall be placed above flood plain.
M. Line Stopping:
Line stopping is used when existing distribution valves do not exist, have failed, or if line stops
are called out on the plans. The line stopping shall be performed following written approval of
the engineer. All line stopping equipment must be disinfected prior to use per ANSI/AWWA
C651/B301. Line stop types shall be utilized in the following order:
1. Permanent Insertion Valves (for pipes with smooth interior walls): valve box and operational
permanent insertion valve line stops shall be installed similar to a gate valve for future
operability. Insertion valves shall be class 250. Insertion valves shall be Insta-ValveTM by
Hydra-Stop, or an approved equal.
2. Temporary Internal Line Stops (for all pipe types): Saddles shall be bolted with stainless
steel bodies and components. Saddles shall be class 250 and compatible with the main
(asbestos cement, PVC, ductile iron, or cast iron pipe, fused (HDPE) or welded (concrete
cylinder pipe)) and line stop equipment. Saddles shall be manufactured by Hydra-Stop, JCM
or an approved equal.
3. HDPE Squeezing: HDPE pipe, up to 8” diameter and not exceeding an operating pressure
of 100psig, may be squeezed-off per the manufacturer’s recommended procedures.
Squeeze-off tools shall be designed for use on HDPE pipe in accordance with AWWA
F1563. The tools and procedures shall be approved by the City prior to use. Squeeze-off
tool shall be manufactured by Footage or an approved equal.
N. Thrust Blocks:
Thrust blocks shall be Class B Portland cement concrete, Type II, meeting Caltrans Standard
Specification Section 90 requirements and sized according to the detail shown on the WGW
Utility Standard Detail WD-13.
O. Shell Cutter:
Shell cutters shall be Mueller, or approved equal, for tapping HDPE 4710, C900 PVC, asbestos
cement (AC), ductile iron (DI), or cast iron (CI) pipe. A shell cutter for both plastic pipe and/or
AC/DI/CI pipe shall be approved by the engineer prior to use. Shell cutters shall be tungsten
carbide tipped, designed for an easy fit through valves, and shall have large slots for debris
removal. "Drill-bit" type cutters shall not be used.
P. Tracer Wire and Connections:
Tracer wire shall be Agave Wire, LTD 10 AWG solid copper wires coated with .45 mils Type
HMW - PE insulated conductor, blue in color, or approved equal. The wire shall meet all
requirements of the latest version of ASTM D1351 and ASTM B8 and shall be UL listed as direct
burial wire for temperatures between -20o C and 80o C for circuits not exceeding 600 volts. The
surface of the insulation shall be durably marked, at intervals not exceeding 24 inches, with only
the following information: maximum working voltage "600 VOLTS", wire type, manufacturer's
name or trademark, AWG size, and UL required markings. Tracer wire shall be installed on all
HDPE pipe mains and services.
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
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One tracer wire shall be installed with the pipe. All tracer wire connections shall be made using
the Nicotap connector system T1-102-D, wrapped with aqua seal and electrical tape. All Nicotap
fittings must be installed with tooling specified by the manufacturer. The use of pliers or other
crimping devices will not be allowed.
Anode boxes, and 5 to 10 lb. Mg anode bags (provided by City), shall be installed at fire hydrants
as directed by the City, with tracer wire extending as shown on WGW Utility Standard Detail WD-
15. For single service installations that are not part of a Capital Improvement Project, anode
boxes, and 1 lb. Mg anode bags (provided by City), shall be installed at water meter, with tracer
wire extending as shown on corresponding WGW Utility Standard Details. The wire configuration
shall be as follows: North tracer wire – terminal 1, no knot, East tracer wire – terminal 2, with one
knot, South tracer wire – terminal 3, with two knots, and West tracer wire – terminal 4, with three
knots.
Q. Warning Tape:
Warning tape shall be Northtown Pipe Protection Products Hytech Non-Detectable Tape, or
approved equal, 3 inches wide, blue and carry the inscription: “Caution Buried Water Line
Below”. Warning tape shall be installed 12 inches above the top of the new water main (initial
backfill zone).
R. Anode Boxes:
Anode boxes shall be Oldcastle Precast/Christy G05TBox Traffic Valve Box with G05CT non-
locking type metal lid marked “Anode Water”.
4.02 MANUFACTURER'S TESTING
A. Health effects evaluation:
All materials in direct contact with potable water, including but not limited to, pipe and fittings
must comply with ANSI/NSF Standard 61.
B. Long-term hydrostatic strength:
Materials must be tested to establish that their minimum long-term hydrostatic strength is in
compliance with the requirements of the applicable AWWA product standard (AWWA C906).
C. Material cell classification:
PE materials must have a cell classification 445574C per ASTM D3350.
4.03 SUBMITTALS AND QUALITY CONTROL
A. The Manufacturer shall submit a written quality control procedure conforming to requirements of
ANSI/AWWA C901 (up to 4”) and C906 (4” and larger), which shall be subject to approval by
engineer.
B. The Manufacturer shall permit City representatives to tour extrusion facilities for the purpose of
evaluating manufacturer's capabilities. The tour shall be during extrusion of a City order or if prior
to order placement during the extrusion of a similar material.
C. The Manufacturer shall certify that the plastic pipe and or fittings supplied meet all the
requirements of this Specification. When requested by the City, the Manufacturer shall supply
certification for all items ordered. Failure to do so shall be cause for order rejection.
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4.04 MATERIAL INSPECTION
City reserves the right to inspect all material and may reject any items not meeting these
Specifications.
PART 5 - EXECUTION
5.01 HDPE WATER MAIN SYSTEM INSTALLATION
A. Valve Boxes/Valve Pits:
Main line valve boxes shall be installed per Section 4.01A.16 of this Specification.
B. Line Stopping:
1. Internal Line Stops (All pipe types): In order to minimize potential traffic hazards, all
excavation and necessary preparation, prior to line stopping and new line valve installation,
shall be done one (1) day in advance prior to the actual plumbing work. Each line valve
installation shall include two (2) line stops, one upstream and one downstream of the line
valve to be replaced, complete with all necessary equipment (i.e., bypass, sawcutters,
backhoes, deck plates, traffic control, etc.) and materials (i.e., piping, disinfectant, couplings,
concrete, AC, backfill, restraint, etc.), needed to assemble and complete installation of the
new line valve.
2. HDPE Squeezing: Squeezing and releasing rates are key elements in squeezing off HDPE
correctly. Squeeze pipe slowly to close, no faster than 2 inches per minute (2ipm) based on
the pipelines outside dimension, release squeeze tool at a rate, no faster than 0.5ipm based
on the pipelines outside dimension, and allow the pipe to naturally rebound. Do not squeeze-
off pipe within 12” or 3x the pipe diameter, whichever is greater, from other fittings or
previous squeezes. After squeeze-off is complete wrap vinyl tape at the squeeze off location
to 6 inches on each side and mark the pipe “Squeeze Off” for future reference.
C. Main Filling:
All main filling shall be done in the presence of the Engineer and/or field inspector, and field
operations personnel. Corporation stops shall be installed on the main so as to remove trapped
air prior to pressure testing.
D. Maximum Pull Force:
A commercially available weak link approved by the Engineer shall be used, in accordance with
manufacturer’s recommendations, between the puller and the pipe during directional drilling
operations. See Section 2300 for maximum allowable pull force for PE 4710 HDPE.
5.02 HDPE WATER SERVICE INSTALLATION
Transfer or reconnection of a water service from the existing main to a new main may cause an
interruption in the customer's service. The contractor must notify the customer via door hanger
notices, 24 hours in advance of the service interruption with the approximate time (8 am -12 pm or 1
pm - 5 pm) and duration of the service interruption. At the time of service interruption, the customer
shall be notified by ringing the door bell or knocking. The customer's main water valve will be closed if
it can be located. After the service has been transferred/reconnected the customer's main water valve
will be opened, and customer's service pipe flushed through a hose bib to remove air, sand, chlorine,
shaving material, etc.
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5.03 WATER METER REPLACEMENT
A. Work Materials to be Furnished by the City: The City will provide new water meters for
replacement where designated by the engineer. All other materials shall be provided by the
Contractor. All meters to be obtained from the City of Palo Alto Water Operations Department.
B. Work Materials to be Furnished by the Contractor shall include, but are not limited to:
1. All materials and equipment needed to complete installation of new HDPE mains, services,
and small/large meter vaults including by-passes.
2. Expendable Concrete Materials: Materials required to install and finish Portland cement
concrete, such as form lumber, tie-wire, nails, etc.
3. Concrete: All Portland cement concrete including reinforcing steel, wire mesh, etc.
4. Temporary and Permanent Fencing: All fencing including traffic barricades required to
provide a barrier between vehicular/pedestrian movements and excavations.
5. Trench Backfill Sand: All backfill sand shall be clean, imported sand, rock and salt free. Bay
sand will not be accepted.
6. Paving Material: All materials required for temporary and permanent street repairs including
base materials.
7. Landscaping Materials: All landscaping materials, plants and surface materials that are
damaged due to Work.
8. Traffic Control Materials: All materials required to direct vehicular/pedestrian traffic, including
striping, loop detectors, reflectors, etc. that may be damaged by the Work.
9. Drilling fluids and bentonite for directional drilling operations.
10. Non-skid trench plates.
11. Project notification signs.
5.04 HDPE HYDRANT ASSEMBLIES AND FIRE SERVICES
Hydrant Assemblies shall be installed and field tested according to the requirements of AWWA M17,
ANSI/AWWA C503, and as shown on the Project Drawings.
Prior to reconnection, all existing fire services shall be potholed by the Contractor to avoid possible
conflicts. Existing fire service pipe shall be joined with new HDPE pipe, connected to a new HDPE
water main by MJ adapter, or as shown on the WGW Utility Standard Details. Contractor may be
required to furnish shop drawings of how re-connection will be constructed and shall inform the
nearest City Fire Station, City Communications Center, and Customers regarding the fire service
work. The Contractor will be required to make all necessary schedule arrangements to accommodate
the customer's needs.
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5.05 Testing and Inspection
The Engineer or Inspector shall have access to the Work area at all times, and the Contractor shall
provide proper facilities for such access and inspection. If the Specifications, the Engineer's
instructions, law, ordinances, or any other public authority require any work to be specially tested or
approved, the Contractor shall give the Engineer 24-hour notice of its readiness for inspection. If the
inspection is by an authority other than the Engineer, the Contractor shall make special arrangements
for the outside authority to make its inspection. Work covered up without approval or consent of the
Engineer or Inspector, shall, if required by the Engineer or Inspector, be uncovered for examination
and properly restored at the Contractor's expense.
Authorized Inspectors are considered to be representatives of the City, limited to the duties and
powers entrusted to them. It will be the Inspectors' duty to inspect materials and workmanship of
those portions of the Work to which they are assigned, either individually or collectively, under the
instructions of the Engineer, and to report any and all deviations from the Project Drawings,
Specifications and other Contract provisions which may come to their notice. An Inspector will order
the Work entrusted to his/her supervision stopped if in his opinion such action becomes necessary.
The Engineer will be notified and will determine if the Work is proceeding in due fulfillment of all
Contract requirements.
All pipe and accessories shall be laid, jointed and tested under pressure for defects and leakage the
manner specified, in the presence of and as approved by the Engineer or Inspector.
A. Connection to Existing Main: The Contractor shall make connections to existing mains where
indicated on the Drawings. All necessary preparation (not limiting to traffic control and
excavation) for system connections shall be done one (1) day prior to actual materials
installation. All new water mains shall be kept isolated from the City system until they are
flushed, bacteriologically tested, and accepted. New system isolation by a closed valve
will not be permitted. The Engineer will review the Contractor's method and sequence of
connecting to existing mains to minimize contamination danger. Connections to existing valves
prior to obtaining satisfactory leakage and pressure tests of the new facilities will not be allowed.
The City assumes no responsibility for the water tightness of existing valves. If necessary, the
Contractor must work with the City to accomplish water tightness. All costs and expenses for
obtaining water tightness shall be included in the bid price for various bid items, and no special
compensation shall be allowed.
Service interruptions on existing mains impacted by a shutdown shall be coordinated with the
Engineer, who will specify time and duration of the interruption. The Contractor shall notify all
affected users in writing at least 48 hours in advance of service interruption. The Contractor shall
notify the City's Water-Gas-Wastewater Operations Division (496-6967) at least 5 days in
advance to schedule valve closures for service interruptions. Manipulation of existing valves
shall only be done by or under the direction of City Water Division personnel.
After the new water system has been flushed, bacteriologically accepted, pressure and leak
tested, and placed into service, all valves in the system shall be maintained in an "on" position
unless otherwise directed by the Engineer.
B. Hydrostatic Pressure and Leak Testing: Installed main shall be adequately anchored with a
covering of at least 6” of initial backfill, if installed by open trench method. The joints and fittings,
particularly flange connections, shall be left uncovered for visual leak inspection.
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Leak tests of the new HDPE water system shall be conducted in accordance with ASTM F2164.
The pipeline should be slowly filled with potable water and all trapped air bled off. The main
should undergo a hydrostatic pressure test using a pressure of 150 psi. The pressure shall be
maintained constant for a 4-hour period by adding makeup water. After 4 hour period is
completed, the pressure shall remain steady within 5% (7.5 psi) of a target 150 psi test pressure
for one hour. The total test time should not exceed 8 hours. If the pipeline has to be retested –
the pipe must be depressurized and allowed to “relax” for at least 8 hour period before the next
testing sequence.
In fused polyethylene water piping system, no leakage shall be present. If leakage is observed at
a fusion joint, complete rupture may be imminent. The Contractor shall move all personnel away
from the joint and depressurize the main. Leaks, failure, or defective construction shall be
promptly repaired by the Contractor, at the Contractor’s sole expense. Payment for pressure and
leakage testing shall be considered included in the price paid per linear foot for water main
installation.
C. Disinfection and Bacteriological Testing: Newly installed potable water pipelines (mains and
services) require disinfection in accordance with ANSI/AWWA C651/B301. Disinfection shall take
place after the initial flushing, and after the completion of the pressure testing. Individual new
water services will be flushed through the angle meter stop after connection to the new water
main. The new pipe, connections, and fittings must be kept clean and swabbed with a 5%
solution of hypochlorite before installation.
Injection of liquid chlorine solution shall be used to disinfect HDPE water pipes. With this method,
the main is filled to remove air pockets and chlorine is injected continuously until a concentration
between 25mg/L and 50 mg/L is obtained throughout the main. The chlorinated water in all
portions of the main shall have a residual of not less than 10 mg/L of free chlorine after a 24-hour
period. Contractor shall note that prolonged exposure to highly concentrated disinfection
chemicals may damage the inside surface of HDPE pipe and shall be avoided. Air is to be
exhausted from each high point, dead end, branch run and hydrant run. The chlorinated water
shall be removed prior to samples being collected for bacteriological testing.
Before bacteriological testing samples are taken, each hydrant run, branch run and dead end
shall be thoroughly flushed to clear highly chlorinated water and until the residual chlorine
concentration reaches normal distribution system levels. If discharging to storm drainage system,
Contractor shall first obtain approval from the City. The Contractor shall measure residual
chlorine concentrations by using a color comparator test that is witnessed and approved by the
Inspector. Samples shall be gathered and tests conducted according to the provisions of AWWA
C651-14, at the expense of the Contractor, by a laboratory approved by the Engineer. Samples
shall be taken at representative points as required to thoroughly test the installed pipe. Fire
hoses and fire hydrants shall not be used to gather samples. The Contractor will be required to
perform two consecutive Coliform tests at a minimum of 16-hours apart. The testing laboratory
used by the Contractor shall be State Certified and provide QA/QC reports.
The new facilities shall remain isolated and out of service until satisfactory test results have been
obtained that meet the requirements of the State Water Resource Control Board, and the
Engineer has accepted the results as indicative of the bacteriological condition of the new water
pipe. If unsatisfactory or doubtful results are obtained from the initial sampling, the pipe (mains
and services) shall be flushed and the chlorination process shall be repeated until acceptable
test results are obtained. The bacteriological test takes at least 48 hours for results to be
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WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
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conclusive.
Disposal of chlorinated water shall comply with all federal, state, and local regulatory
requirements. Disposal directly to the storm drain system without removal of chlorine is strictly
prohibited. No discharge into the storm drain system shall be allowed during rain. Upon
termination of the flushing, any standing water in the gutter shall be removed by sweeping it to
the nearest storm drain catch basin or sewer manhole. Flushing of chlorinated water directly into
the sanitary sewer system will only be allowed with Engineer’s approval.
If new water mains will not be tied into the water distribution system within 72 hours following the
Engineer’s acceptance of the bacteriological test results, Contractor may be required to flush the
highly chlorinated water from the main, refill the main with potable water, and maintain pressure
in the main until the tie-in is complete. If the main is allowed to sit empty for a period longer than
24 hours, the Contractor will be required to repeat flushing, disinfection and bacteriological
testing procedures at the Contractor’s expense.
D. Washing/Flushing Vehicles: All vehicles used for street washing or flushing must be equipped
with meters and have air gap separation connections to hydrants and filling tanks.
5.06 Water Service Abandonment Procedure
A. Excavate existing water service at the main.
B. Service with a corporation stop and service saddle: turn off corporation stop and check for leaks.
Cut the copper or HDPE tubing with a tubing cutter and bend both cut ends over approximately
1" from cut end (copper service) or electrofuse HDPE electro fusion end cap (HDPE service).
C. Service with a corporation stop with no service saddle: notify and coordinate with all affected
Customers, along with City Utility Operations staff, of the pending service interruption. Remove
corporation stop and install a Mueller or Ford repair clamp. Any leaks, failures, or defective
repairs shall be promptly repaired by the contractor.
D. Remove water meter and salvage to the City of Palo Alto corporation yard water meter repair
shop.
E. Remove abandoned water meter vault. Backfill and compact hole to City standards with top soil
or clay dirt.
F. Backfill, compact and pave hole at the main per WGW Utility Standard Detail WGW-02.
G. Abandonment of all existing water services shall be witnessed by the City’s Utilities Inspector.
Schedule WGW utilities inspections at 650/566-4501 five working days before start of
abandonment.
5.07 Procedure for Disconnecting Large Service with Tapping Tee and Valve
A. Provide a 72-hour notification of service interruption to all affected water customers. Coordinate
water shutdown with affected customers and Utilities Engineering/Operations staff. The
shutdown plan must be approved by the City prior to shutting down the water service.
B. Shut down the main and excavate existing fire hydrant or service at the main.
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C. For hydrant service or water service with tapping saddle, remove the tapping saddle and install a
Mueller repair clamp. Any leaks, failures, or defective repairs shall be promptly repaired by the
contractor.
D. For service with a tee, remove the tee and replace the section with HDPE or PVC C-900 straight
pipe. Use fully-restrained mechanical couplings for straight pipe connections to existing non-
HDPE pipe. Couplings model and manufacturer shall be approved by City.
5.08 ACP Pipe and Hazardous Material Disposal
Asbestos containing pipe must be properly disposed of per State and Federal regulations. Contractor
and subcontractors, if any, shall be in full compliance with any and all laws, orders, citations, rules,
regulations, standings and statutes in effect with respect to handling, storage and removal of
Hazardous Material. Contractor accepts sole responsibility for insuring the adequacy of any required
use of all safety practices, procedures and equipment.
END OF SECTION
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SECTION 2685
NATURAL GAS DISTRIBUTION SYSTEM
PART 1 - GENERAL
1.01 DESCRIPTION
Work includes installation of natural gas mains, natural gas services, tracer wire, polyethylene valves
and boxes, polyethylene fittings, excess flow valves, anode boxes, modification of existing natural
gas house plumbing to accommodate relocation of gas meters, and all related equipment and fittings
in accordance with the requirements of the Contract Documents.
1.02 RELATED WORK
A. Section 2200: Excavation, Backfill, and Restoration
B. Section 2300: Polyethylene Pipe Installation for Water, Gas, and Wastewater
1.03 QUALIFICATION OF NATURAL GAS DISTRIBUTION SYSTEM CONTRACTOR
The Contractor performing work on the City of Palo Alto natural gas distribution system shall have
and must submit for approval by the City of Palo Alto a drug-testing program in place per Pipeline
Safety Regulations Part 199 "Drug Testing Pipeline Safety" and Part 40 "Procedures for
Transporting Workplace Drug and Alcohol Testing Programs" and Management Information
Sheets for each year requested by the City Project Manager.
PART 2 - MATERIALS
2.01 NATURAL GAS DISTRIBUTION SYSTEM MATERIALS
A. POLYETHYLENE PIPE: Polyethylene pipe supplied under this section shall be in compliance
with ASTM D2513-09a “Standard Specification for Polyethylene (PE) Gas Pressure Pipe, Tubing
and Fittings”, incorporated by reference into Code of Federal Regulations (CFR) Title 49, Part
192.7 and specifications stated herein:
1. All pipe shall be Medium Density Polyethylene (MDPE) 2708 pipe, uniformly yellow in color,
conforming to the latest edition of ASTM D3350 “Standard Specification for Polyethylene
Plastics Pipe and Fittings Materials”, cell classification 234373E. extruded from one of the
following: Performance Pipe Company Marlex HHM TR-418Q Resin or Ineos Fortiflex® K38-
20-160 Resin.
a. In special circumstances and upon approval, High Density Polyethylene (HDPE) 4710
pipe, uniformly black in color with four (4) equally placed stripes, conforming to the latest
edition of ASTM D3350 “Standard Specification for Polyethylene Plastics Pipe and
Fittings Materials”, cell classification 445574C, may be used.
2. Pipe dimensions and tolerances: The outside diameter and wall thickness shall be within
the limits specified in Table 1 for MDPE pipe.
3. Markings: All pipe markings for gas pipe shall be in compliance with the latest edition of
ASTM F2897 “Standard Specification for Tracking and Traceability Encoding System of
Natural Gas Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)”
and consist of a 16-digit alpha-numeric code and scannable code-128 barcode, or QR code,
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NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
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with standardized encoding of pipe specifications as described in the referenced Standard. In
addition, gas pipe markings shall also comply with the marking requirements for all
polyethylene pipe specified in Section 2300 of these Specifications.
4. Approved Manufacturers: The City of Palo Alto approved PE pipe manufacturer is Chevron
Phillips Chemical Company (CP CHEM) Performance Pipe. Any other pipe manufacturer
such as JM Eagle or equal must receive prior approval.
Table 1: Dimensional Standards for Polyethylene Pipe and Tubing (Per ASTM D2513)
Nominal
Pipe/
Tubing
Size
Average
Outside
Diameter
(inches)
Outside
Diameter
Tolerance
(inches)
Minimum
Wall
Thickness
(inches)
Wall
Thickness
Tolerance
(inches)
Out of
Roundness
Tolerance
(inches)
Standard
Dimension
Ratio
(unitless)
1" CTS 1.125 ± 0.005 0.099 + 0.012
- 0.000
- -
2" IPS 2.375 ± 0.006 0.216 + 0.026
- 0.000
± 0.024 11.0
3” IPS 3.500 ± 0.008 0.304 + 0.036
- 0.000
± 0.030 11.5
4" IPS
4.500 ± 0.009 0.391 + 0.047
- 0.000
± 0.030 11.5
6" IPS
6.625 ± 0.011 0.576 + 0.069
- 0.000
± 0.070 11.5
8" IPS 8.625 ± 0.013 0.750 + 0.090
- 0.000
± 0.080 11.5
Note: 3” IPS PE pipe shall only be used for the repair of existing 3” PE pipe.
B. PE Fittings: All molded polyethylene fittings supplied under this section shall be in compliance
with ASTM D2513-09a “Standard Specification for Polyethylene (PE) Gas Pressure Pipe, Tubing
and Fittings”, incorporated by reference into CFR Title 49, Part 192.7 and ASTM D3261
“Standard Specification for Butt Heat Fusion Polyethylene (PE) Plastic Fittings for Polyethylene
(PE) Plastic Pipe and Tubing”, and specifications stated herein:
1. All fittings shall be Medium Density Polyethylene (MDPE) 2708 fittings, uniformly yellow in
color, conforming to the latest edition of ASTM D3350 “Standard Specification for
Polyethylene Plastics Pipe and Fittings Materials”, cell classification 234373E. molded from
one of the following: Performance Pipe Company Marlex HHM TR-418Q Resin; or Ineos
Fortiflex® K38-20-160 Resin.
a. In special circumstances and upon approval, High Density Polyethylene (HDPE) 4710
fittings, uniformly black in color, conforming to the latest edition of ASTM D3350
“Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”, cell
classification 445574C (Black), may be used.
2. Dimensions and tolerances: Butt Fusion Fittings shall conform to the dimensions given in
Table 2.
3. Approved Manufacturers: The City of Palo Alto approved PE fitting manufacturer is
Chevron Phillips Chemical Company (CP CHEM) Performance Pipe. Any other pipe
manufacturer such as CSR Poly Pipe Industries or equal must receive prior approval.
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NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
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Table 2: Dimensional Standards for Polyethylene Butt Fusion Fittings
Nominal
Fitting
Size
Ave Outside
Dia at Point
of Fusion
(inches)
Outside
Diameter
Tolerance
(inches)
Minimum
Wall
Thickness
(inches)
SDR
(unitless)
Minimum
Stub
Length*
(inches)
2" IPS 2.375 ± 0.006 0.216 11.0 2.0
4" IPS 4.500 ± 0.009 0.391 11.5 3.0
6" IPS 6.625 ± 0.011 0.576 11.5 3.5
8" IPS 8.625 ± 0.025 0.750 11.5 3.5
* As defined in Figure 1 (only applicable to tees, 45° and 90° ells).
Figure 1: Definition of Stub Length for Butt Fusion Fittings
STUB LENGTH-S
S PORTIONS O.D. CONTROLLED
TO MATCH PIPE O.D.
C. Polyethylene Gas Valves: All polyethylene gas valves supplied under this section shall be in
compliance with ASTM D2513 “Standard Specification for Polyethylene (PE) Gas Pressure Pipe,
Tubing and Fittings”, CFR Title 49, Part 192.145 “Valves” and the latest editions of ANSI/ASME
B16.40 “Manually Operated Thermoplastic Gas Shutoffs and Valves in Gas Distribution
Systems”, and specifications stated herein:
1. The polyethylene portion of the gas valve shall be one-piece molded medium density PE
2708 polyethylene conforming to the latest edition of ASTM D3350 “Standard Specification
for Polyethylene Plastics Pipe and Fittings Materials”, cell classification 234373E
manufactured from Performance Pipe Company Marlex HHM TR-418Q Resin, Rigidex PC
2040Y, or FINATHENE 3802Y.
2. All polyethylene gas valves shall be manufactured within 6 months from the date of sale to
the City.
3. All polyethylene gas valves shall be full port, assembled to operate smoothly and provide a
gas tight seal(s). Polyethylene gas valves shall utilize a 2” square operating nut with positive
position indication and over-torque protection actuator. Each valve’s stem shall be equipped
with weather seal(s) protecting inner parts from ground water and foreign debris intrusion. All
polyethylene valves shall be supplied with the butt end outlets.
4. For purging at designated locations, Flowserve Corp. (Nordstrom Valves) with integral
polyethylene purge connections shall be used. These valves shall comply with all
specifications for polyethylene gas valves of this section.
5. Markings: Polyethylene gas valve markings shall be in compliance with the latest edition of
ASTM F2897 “Standard Specification for Tracking and Traceability Encoding System of
Natural Gas Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)”
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NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
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and consist of a 16-digit alpha-numeric code and scannable code-128 barcode, or QR code,
with standardized encoding of pipe specifications as described in the referenced Standard.
6. Approved Manufacturers: The City of Palo Alto approved PE gas valve manufacturer is
Flowserve Corp. Polyvalve Poly-Gas (Formally Nordstrom Valves). Any other pipe
manufacturer such as Kerotest Manufacturing Corp (PolyBall), or Broen, Inc. (Ballomax)CSR
Poly Pipe Industries or equal must receive prior approval.
Table 3: Dimensional Standards for Full Port Polyethylene Valves
VALVE SIZE SDR MIN. PORT DIA.* MIN. STUB LENGTH*
2" 11 1.82" 4.2"
4" 11.5 3.62" 3.1"
6" 11.5 5.20" 3.9"
8" 11.5 6.60" 7.0"
*as defined in Figure 2
Figure 2: Definition of Dimensions for Polyethylene Valves
D. Gas Service Riser (Anodeless): Risers must meet or exceed the latest editions of the following
standards or requirements:
x Department of Transportation (DOT) Code of Federal Regulations, Title 49, Part 192.
x ASTM D2513 “Standard Specification for Tracking and Traceability Encoding System of
Natural Gas Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)”
x ANSI B1.20.1 “Pipe Threads, General Purpose, Inch”, latest edition
x ASTM G8 “Standard Test Methods for Cathodic Disbonding of Pipeline Coatings”, latest
edition
x 100% factory leak tested
x Polyethylene pigtail markings shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of
a 16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with
standardized encoding of pipe specifications as described in the referenced Standard.
1. Prebent Risers:
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NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
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a. Anodeless 1"PE CTS X ¾" MPT PREBENT: The 1" casing pipe shall be fabricated
from ASTM A53 schedule 40, Grade A steel pipe. The casing shall also conform to the
following requirements: gray fusion bonded epoxy coated (8 mil minimum thickness); 46
inches long, 1.500” OD x 0.075” wall thickness; ASTM A513 mechanical tubing with ¾"
MPT nipple outlet and neoprene bushing, crimped in place, moisture seal. Additionally,
the casing pipe shall be bent to a 12-inch minimum radius resulting in a min. 16"
horizontal by 30" vertical configuration.
A minimum 10-inch-long, 1" CTS (0.099 wall thickness) PE pigtail shall extend from the
steel pipe casing. The 1" CTS carrier pipe shall be medium density PE 2708
polyethylene, uniformly yellow in color, conforming to the latest edition of ASTM D3350
“Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”, cell
classification 234373E extruded from one of the following Performance Pipe Company
Marlex HHM TR-418Q Resin or Ineos Fortiflex® K38-20-160 Resin.
The transition from steel to PE shall occur within 6 inches of the threaded end. Risers
shall include insulation between the steel casing and the PE carrier pipe by means of an
o-ring/air space configuration or using a sleeve made of non-heat conducting materials.
All exposed threads and openings shall be covered with protective caps. The riser label
shall include manufacturers name, part number, lot number and casing pipe shall have
indication of ground level.
Anodeless risers must have approved meter valves included.
b. Anodeless 1"PE CTS X 1-1/4" MPT PREBENT: The 1-1/4" casing pipe shall be
fabricated from ASTM A53 Schedule 40, Grade A steel pipe. The casing shall also
conform to the following requirements: gray fusion bonded epoxy coated (8 mils
minimum thickness); 60 inches long, 1.625” O.D. x 0.072 wall thickness; ASTM A513
mechanical tubing with 1-1/4" MPT nipple outlet and neoprene bushing, crimped in
place, moisture seal. Additionally, the casing pipe shall be bent to a 12-inch minimum
radius resulting in a 30" horizontal by 30" vertical configuration.
A minimum 10-inch long, 1" CTS (0.099 wall thickness) PE pigtail shall extend from the
steel pipe casing. The 1” CTS carrier pipe shall be medium density PE 2708
polyethylene, uniformly yellow in color, conforming to the latest edition of ASTM D3350
“Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”, cell
classification 234373E extruded from one of the following: Performance Pipe Company
Marlex HHM TR-418Q Resin or Ineos Fortiflex® K38-20-160 Resin.
The transition from steel to PE shall occur within 6 inches of the threaded end. Risers
shall include insulation between the steel casing and the PE carrier pipe by means of an
o-ring/air space configuration or using a sleeve made of non-heat conducting materials.
All exposed threads and openings shall be covered with protective caps. The riser label
shall include manufacturers name, part number, lot number and casing pipe shall have
indication of ground level.
Anodeless risers must have approved meter valves included.
c. Anodeless 2"PE IPS X 2" MPT PREBENT: The 2" casing pipe shall be fabricated from
ASTM A53 Schedule 40, Grade A steel pipe. The casing shall also conform to the
following requirements: gray fusion bonded epoxy coated (8 mil minimum thickness); 72
inches long, 2" MPT nipple outlet and neoprene bushing, crimped in place, moisture
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seal. Additionally, the casing pipe shall be bent to a 24-inch minimum radius resulting in
a 36" horizontal by 36" vertical configuration.
A minimum 10-inch long, 2" IPS (0.216 wall thickness) PE pigtail shall extend from the
steel pipe casing. The 2” IPS carrier pipe shall be medium density PE 2708
polyethylene, uniformly yellow in color, conforming to the latest edition of ASTM D3350
“Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”, cell
classification 234373E extruded from one of the following: Performance Pipe Company
Marlex HHM TR-418Q Resin or Ineos Fortiflex® K38-20-160 Resin; SDR 11.0.
The transition from steel to PE shall occur within 6.5 inches of the threaded end. Risers
shall include insulation between the steel casing and the PE carrier pipe by means of an
o-ring/air space configuration or using a sleeve made of non-heat conducting materials.
All exposed threads and openings shall be covered with protective caps. The riser label
shall include manufacturers name, part number, lot number and casing pipe shall have
indication of ground level.
Anodeless risers must have approved meter valves included.
2. Straight Risers:
a. Anodeless 1"PE CTS X ¾" MPT STRAIGHT - The ¾" casing pipe shall be fabricated
from ASTM A53 Schedule 40, Grade A steel pipe. The casing shall also conform to the
following requirements: gray fusion bonded epoxy coated (8 mils minimum thickness);
60 inches long, 1.500” OD x 0.072” wall thickness; ASTM A513 mechanical tubing with
¾" MPT nipple outlet and neoprene bushing, crimped in place, moisture seal.
A minimum 10-inch-long, 1" CTS (0.099 wall thickness) PE pigtail shall extend from the
steel pipe casing. The 1" CTS carrier pipe shall be medium density PE 2708
polyethylene, uniformly yellow in color, conforming to the latest edition of ASTM D3350
“Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”, cell
classification 234373E extruded from one of the following Performance Pipe Company
Marlex HHM TR-418Q Resin or Ineos Fortiflex® K38-20-160 Resin.
The transition from steel to PE shall occur within 6.5 inches of the threaded end. Risers
shall include insulation between the steel casing and the PE carrier pipe by means of an
o-ring/air space configuration or using a sleeve made of non-heat conducting materials.
All exposed threads and openings shall be covered with protective caps. The riser label
shall include manufacturers name, part number, lot number and casing pipe shall have
indication of ground level.
Anodeless risers must have approved meter valves included.
b. Anodeless 2"PE IPS X 2" MPT STRAIGHT - The 2" casing pipe shall be fabricated
from ASTM A53 Schedule 40, Grade A steel pipe. The casing shall also conform to the
following requirements: gray fusion bonded epoxy coated (8 mil minimum thickness); 72
inches long, 2" MPT nipple outlet and neoprene bushing, crimped in place, moisture
seal.
A minimum 10-inch long, 2" IPS (0.216 wall thickness) PE pigtail shall extend from the
steel pipe casing. The 2” IPS carrier pipe shall be medium density PE 2708
polyethylene, uniformly yellow in color, conforming to the latest edition of ASTM D3350
“Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”, cell
classification 234373E extruded from one of the following: Performance Pipe Company
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Marlex HHM TR-418Q Resin or Ineos Fortiflex® K38-20-160 Resin; SDR 11.0.
The transition from steel to PE shall occur within 6.5 inches of the threaded end. Risers
shall include insulation between the steel casing and the PE carrier pipe by means of an
o-ring/air space configuration or using a sleeve made of non-heat conducting materials.
All exposed threads and openings shall be covered with protective caps. The riser label
shall include manufacturers name, part number, lot number and casing pipe shall have
indication of ground level.
Anodeless risers must have approved meter valves included.
3. Approved Manufacturers: The City of Palo Alto approved anodeless gas riser manufacturer
is RW Lyall & Company, Inc. Any other anodeless gas riser manufacturer such as Elster
Perfection, Continental Industries, George Fischer Central Plastics Company, or equal must
receive prior approval.
E. Electrofusion Tapping Tees and Couplings: All electrofusion tapping tees and couplings
supplied under this section shall be in compliance with ASTM F1055-1998 “Standard
Specification for Electrofusion Type Polyethylene Fittings for Outside Diameter Controlled
Polyethylene Pipe and Tubing”, and be manufactured in accordance with ASTM D2513-09a
“Standard Specification for Polyethylene (PE) Gas Pressure Pipe, Tubing and Fittings”.
1. All electrofusion tapping tees shall be DAA designated: 1-1/4” x 1”, 2" x 1", 4" x 1", 6" x 1",
and 8" x 1" (IPS x CTS) and, 4" x 2", 6" x 2", and 8" x 2" (IPS x IPS) - main size x outlet size.
2. All electrofusion couplings 1-1/4” and larger (including coupling reducer 2” x 1-1/4”) shall be
IPS, 4710 HDPE; SDR 11 (2” x 1-1/4” and 2”) and SDR 11.5 (4” through 8”) ANSI/NSF 61
listed; 1” coupling shall be CTS, 4710 HDPE.
3. Markings: Electrofusion tapping tee and coupling markings shall be in compliance with the
latest edition of ASTM F2897 “Standard Specification for Tracking and Traceability Encoding
System of Natural Gas Distribution Components (Pipe, Tubing, Fittings, Valves, and
Appurtenances)” and consist of a 16-digit alpha-numeric code and scannable code-128
barcode, or QR code, with standardized encoding of pipe specifications as described in the
referenced Standard.
4. Approved Manufacturers: The City of Palo Alto approved electrofusion gas tapping tee and
coupling manufacturer is Friatec (Frialen Safety Fittings). Any other electrofusion gas tapping
tee and coupling manufacturer such as Kerotest (Innogaz Electrofusion Products) or equal
must receive prior approval.
F. Valve Boxes: Valve boxes for 2” through 8” valves shall be Oldcastle Precast/Christy G05TBox
Traffic Valve Box with G05CT non-locking type metal traffic type lid marked “GAS”. Corrugated
8” HDPE pipe shall be used as valve box extension for gas valve sizes 2” through 8" diameter.
Valve supports shall be supplied for 2" valve sizes only and be manufactured by C. P. Test
Services Inc., model FPKPV2.3, or approved equal.
G. Tracer Wire: Tracer wire shall be 10 AWG solid copper wire coated with 45 mils Type HMW - PE
insulated conductor, yellow in color. The wire shall meet all requirements of the latest editions of
ASTM D1351 and ASTM B8 and shall be UL listed as direct burial wire for temperatures between
-20o C and 80o C for circuits not exceeding 600 volts. The surface of the insulation shall be
durably marked, at intervals not exceeding 24 inches, with only the following information:
maximum working voltage "600 VOLTS", wire type, manufacturer's name or trademark, AWG
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size, and UL required markings. Tracer wire shall be installed on all polyethylene mains and
services.
H. Meter Valve: Meter valves shall meet all applicable parts of CFR Title 49, Part 192 and
ASME/ANSI B16.33, and shall be insulated Mueller H-11179 (3/4", 1-1/4", or 2"), with a 3/4", 1-
1/4", or 2" steel plug. Bypass valves shall be non-insulated Mueller H-11175 (3/4”, 1-1/4”, or 2”)
with a 3/4”, 1-1/4”, or 2” steel plug. The City of Palo Alto approved meter valve manufacturer is
Mueller Company. Any other meter valve manufacturer must receive prior approval.
I. Anode Boxes: Anode box shall be Oldcastle Precast/Christy G05TBox Traffic Box with G05CT
non–locking type metal traffic lid marked "ANODE".
J. Warning Tape: Warning tape must be non-metallic, a minimum of 6” wide, “yellow” in color and
have the following print line” CAUTION: GAS LINE BURIED BELOW”. Warning tape must be
installed in all open excavations at 12” above the natural gas pipeline.
K. Excess Flow Valves (EFV): All EFVs supplied under this section shall be in compliance with the
requirements of CFR Title 49, Part 192.381 “Service lines: Excess Flow Valve Performance
Standards” and, where applicable, MSS SP-115 “Excess Flow Valves, NPS 1-1/4” and Smaller,
for Fuel Gas Service”. All EFVs shall be tested in accordance with the latest edition of ASTM
F1802 “Standard Test Method for Performance Testing of Excess Flow Valves”.
1. All EFVs must be manufactured within 6 months of the date of sale to the City.
2. The design of excess flow valves shall incorporate a bypass to allow the valve to
automatically reset and resume normal operation after repairs are made to the severed gas
line. Each valve shall be fixed or anchored to the interior of the fitting to preclude movement
of the valve.
3. The polyethylene portion of EFV shall be one piece molded medium density PE 2708
polyethylene confirming to the latest edition of ASTM D3350 “Standard Specification for
Polyethylene Plastics Pipe and Fittings Materials”, cell classification 234373E extruded from
one of the following: Performance Pipe Company Marlex HHM TR-418Q Resin or Ineos
Fortiflex® K38-20-160 Resin.
4. Each valve also shall have an affixed tag, identifying the EFV’s capacity range and flow
direction, and be individually packaged and supplied with the operating instructions. An
additional stainless-steel tag or washer shall be included in the package indicating the size
and flow capacity of the valve, which will be attached to the gas riser.
5. Markings: EFV markings shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of
a 16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with
standardized encoding of pipe specifications as described in the referenced Standard.
6. Approved Manufacturers: The City of Palo Alto approved EFV manufacturer is UMAC. Any
other EFV manufacturer such as Elster Perfection or equal must receive prior approval.
a. APPROVED MODELS (shall be designed for electrofusion applications):
UMAC
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Model 41, 1” CTS Series 1800
Model 41, 1” CTS Series 2600
Model 41, 1-1/4” IPS Series 5500
Model 41, 2” IPS Series 5500
Model 41, 2” IPS Series 10000
Table 4: EFV Trip and Load Information
EFV Models
Inlet
Pressure
(PSIG)
Pressure Drop at
Typical Load
(PSIG)
Minimum
Trip Point
(SCFH)
Service Length
Protected
(FT)
Model 41, 1” CTS, Series 1800 10 0.44 1800 213
Model 41, 1” CTS, Series 2600 10 0.9 2600 205
Model 41, 1-1/4” IPS, Series 5500 10 1.3 5500 23
Model 41, 2” IPS, Series 5500 10 1.3 5500 1899
Model 41, 2” IPS, Series 10,000 10 0.51 10,000 667
b. DESIGNATION:
i. 1” Service (CTS):
Medium Capacity: Model 41, 1” CTS, Series 1800 – typical customer load between
250 SCFH and 1,600 SCFH.
High Capacity (I): Model 41, 1” CTS, Series 2600 – typical customer load between
1,400 SCFH and 2,200 SCFH.
High Capacity (II): Model 41, 1-1/4” IPS, Series 5500 – typical customer load
between 2,000 SCFH and 4,800 SCFH. This EFV requires transition from 1-1/4”
IPS to 1” CTS, as 1” CTS for this size is not available.
ii. 2” Service (IPS):
Medium Capacity: Model 41, 2” IPS, Series 5500 – typical customer load 4,800
SCFH or less
High Capacity: Model 41, 2” IPS, Series 10,000 - typical customer load between
4,400 SCFH and 8,800 SCFH
Pressure Drop: An average pressure drop across EFV at an inlet pressure of 10
psig shall not exceed: for 1” CTS - 0.6 psig @ 700 scfh, 1.1 psig @ 1800 scfh, 1.1
psig @ 2600 scfh, and 1.3 psig @ 5500 scfh.
Dimensions: 1” EFV shall be 1” CTS with 0.099” min. wall thickness with a
minimum length of 10”. 2” EFV shall be 2” IPS SDR 11 with 0.216” min. wall and a
minimum length of 10”. Valves shall be supplied with plain pipe ends.
iii. Installation: EVFs shall be installed in compliance with CFR Title 49, Part 192.383
“Excess Flow Valve Installation”. If EFV on a service line is not feasible due to
customer application (can interfere with normal operation) or is not commercially
available, in compliance with CFR Title 49, Part 192.385 “Manual Service Line Shut-
Off Valve Installation”, a manual service line shut-off valve near the source of gas
must be installed.
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L. Meter Boxes: Curb meter installation in sidewalk or planting strip will be allowed only when there
is no above ground location on the property (the building occupies the entire property or
underground parking garage prohibits above ground installation). All meter boxes shall be
supplied and installed by the Contractor when box replacement is required, or a new service is
installed. Meter boxes and lid shall have H-20 load rating and shall not be installed in driving
lanes of public or private streets. Lids shall have “GAS” marked on them.
x Armorcast 24”x36”x18” Polymer Concrete Box Assembly (Part No. A6001974PCX18-1
Each/Assembly), Polymer Concrete Cover (Part No. A6001975TDZ-1 Each/Assembly), RPM
Drop-In Reading Lid Marked as “GAS” (Part No. A6000482T-H7-1 Each/Assembly), Polymer
Concrete Plug (Part No. A60000H7-PLUG-CPA – 1 Each/Assembly), and Box Extension (Part
No. A6001974PCX12-3 Each).
x Armorcast 30”x60”x36” Polymer Concrete Vault Assembly (Part No. A6001460PCX36-1
Each/Assembly), Polymer Concrete Cover (Part No. A6001456TDZ-2 Each/Assembly), RPM
Drop-In Reading Lid Marked as “GAS” (Part No. A6000482T-H7-2 Each/Assembly), Polymer
Concrete Plug (Part No. A60000H7-PLUG-CPA – 2 Each/Assembly),and Box Extension (Part
No. A6001974PCX12-1 Each).
M. Valve Extensions for Polyethylene Gas Ball Valves: Valve extensions shall be installed when
the valve’s actuator is 4’ or more below the finished grade. The extension shall be a telescopic
spindle designed to operate polyethylene gas ball valves (with 2” operating square actuator)
specified in Section 2.01 of this Specification. The extension design shall incorporate the
following features:
x The conical key adaptor that fits most standard T-keys.
x Lock spring preventing the telescopic part from collapsing during installation.
x Protection again penetration of impurities under key adaptor.
x Yellow indication plate with the inscription “1/4” turn, “Ball valve” and indication of “Open-Close”
positions.
x Key adaptor – cast stainless steel.
x Inner tube – galvanized steel.
x Outer tube – polyethylene.
x Actuator adaptor – stainless steel designed to operate 2” operating square actuator.
Approved Manufacturers: The City of Palo Alto approved valve extension manufacturer is
American AVK Co. Any other valve extension manufacturer must receive prior approval.
2.02 STEEL GAS MATERIAL
A. Steel Pipe - Gas Carrier: All steel pipe supplied under this Section shall conform to the
requirements stated in CFR Title 49, Part 192.55 “Steel Pipe” and shall conform to the latest
edition of ASTM A106/A53, Type E (Electric-resistance-welded) or S (seamless), Schedule 40,
Grade B steel pipe. The pipe shall contain markings in accordance with requirements of CFR
Title 49, Part 192.63 “Marking of Materials”, including pipe manufacturer’s name, material, size,
type, grade, pressure ratings, and date of pipe manufacture.
Markings: Pipe marking shall be in compliance with the latest edition of ASTM F2897 “Standard
Specification for Tracking and Traceability Encoding System of Natural Gas Distribution
Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of a 16-digit
alpha-numeric code and scannable code-128 barcode, or QR code, with standardized encoding
of pipe specifications as described in the referenced Standard.
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B. Steel Pipe – Gas Carrier Coating: The external protective coating shall be in compliance with
CFR Title 49, Part 192.461 “External Corrosion Control: Protective Coating”, and NACE. The
pipe shall be coated by application of Fusion Bonded Epoxy (FBE). The coating resin shall be
virgin, high density polyethylene 30 mil extruded coatwrap. The resin color shall be yellow. The
coating shall contain markings including pipe manufacturer’s name, material, size, type, grade,
pressure rating, coating manufacturer’s name, date of pipe manufacture and date of coating.
Steel Pipe – Gas Carrier Rehabilitation Coating System minimum requirements:
x Must meet all applicable NACE standards.
x Must comply with requirements of CFR Title 49, Part 192.461 “External Corrosion
Control: Protective Coating”.
x Must not interfere with Cathodic Protection and prevent cathodic disbondment.
x Shall be designed by manufacturer for application directly on and being compatible with
the existing coating.
x Require minimal surface preparation.
x Shall be multilayer system including at min. primer, coating (wrap – wax tape), and, if
necessary, in the opinion of Cathodic Technician, outerwrap for above or below ground
application.
x Shall be able to conform to irregular shapes including pipe supports and fasteners (above
ground application attached to the bridges).
x Must resist weathering and UV (above ground application).
x Nontoxic, noncarcinogenic, minimum VOCs.
x Provide great adhesion and cohesive and tensile strength.
x Be able to withstand deformation of the substrate.
x Impact resistance per the latest edition of ASTM G14 “Standard Test Method for Impact
Resistance of Pipeline Coatings (Falling Weight Test).
x Dielectric strength per the latest edition of ASTM D149 “Standard Test Method for
Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating
Materials at Commercial Power Frequencies”.
x Puncture resistant.
x Fast drying/curing compounds.
x Must comply with all applicable Environmental Regulations.
x Must be installed in accordance with the system manufacturer’s recommendations.
Approved Coating System(s):
x Primer- Trenton Temcoat 3000, or approved equal.
x Coating – Trenton #1 Wax-Tape (below ground application) or approved equal. If in the
opinion of Cathodic Technician additional mechanical protection is required and
depending on the soil/backfill conditions apply either Poly-Ply, Guard-Wrap, Glas-Wrap,
or MC Outerwrap. No drying or curing time is required and after application the pipe can
be immediately backfilled.
x Coating – Trenton #2 Wax-Tape (above ground application) or approved equal. If in the
opinion of Cathodic Technician additional mechanical protection is required apply Trenton
MC Outerwrap. Trenton #2 Wax-Tape can be painted using an acrylic latex paint.
Depending on atmospheric conditions shall be allowed 2-14 days before paint
application.
C. Steel Valves: All steel valves supplied under this Section shall conform to CFR Title 49, Part
192.145 “Valves”, and meet the minimum requirements of the latest edition API 6D
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“Specifications for Pipeline Valves”. The valve shall be ANSI class 150 (unless specified higher
during specific order), ball valve with weld ends full port only for 2”, 4”, 6”, 8”, 10” sizes; reduced
port for 12” size is allowed if full port is unavailable. Each valve shall be manufacture air tested
to ensure integrity and leak tightness. The valves shall be shipped with 2” operating squares (2”
through 6”) and gear operator (8” through 12”) with cast steel ultra-stop, unless specified
otherwise during the order. The valve shall have markings stating at minimum manufacturer,
size, pressure rating/class, and date of manufacture. The minimum end-to-end length for weld
end valves shall be as follows:
x 2” – 11.81” (full port)
x 4” – 12.80” (full port)
x 6” – 15.35” (full port)
x 8” - 18.00” (full port)
x 10” – 21.50” (full port)
x 12” – 23.50” (full port)
Markings: Gas Valve marking shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of a
16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with standardized
encoding of pipe specifications as described in the referenced Standard.
Approved Manufacturer: The City of Palo Alto approved steel valve manufacturer for 2” through
6” is Kerotest Weldball and for 8” through 12” is Cameron (T31). Any other steel valve
manufacturer such as Ballomax by Broen, Inc. or equal must receive prior approval.
D. Flanges: Each flange or flange accessory shall conform to CFR Title 49, Part 192.147 “Flanges
and Flange Accessories”, and must meet the minimum requirements of ASME/ANSI B16.5-03
“Pipe Flanges and Flanged Fittings” and MSS SP-44-10 “Steel Pipe Flanges”. Flange shall be
ANSI class 150, pressure rating 285 PSIG, unless specified otherwise. Material shall be carbon
steel and shall conform to the requirements of the latest edition of ASTM A105 “Standard
Specification for Carbon Steel Forgings for Piping Applications”.
Markings: Flange marking shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of a
16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with standardized
encoding of pipe specifications as described in the referenced Standard.
E. Non-Pressure Control Fittings: Fittings shall conform to CFR Title 49, Part 192.149 “Standard
Fittings”. All welded fittings shall be schedule 40 and shall comply with the latest editions of
ASTM A234 “Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel
for Moderate and High Temperature Service” (materials) and ASME B16.9 “Standards for Pipes
and Fittings” (dimensions). All threaded fittings shall be malleable iron, IPT, finish black (BLK),
conforming to the latest editions of ASTM A197 “Standard Specification for Cupola Malleable
Iron” (materials) and ASME B16.3 “Malleable Iron Threaded Fittings” (dimensions).
Markings: Fitting markings shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of a
16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with standardized
encoding of pipe specifications as described in the referenced Standard.
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F. Pressure Control Fittings: Fittings top and bottom halves shall be forged steel and be in
compliance with the latest edition of ASTM A105 “Standard Specification for Carbon Steel
Forgings for Piping Applications”. All fittings shall have a class 150 flange and meet
requirements of ANSI B16.5 “Flanges and Bolt Dimensions Class 150 to 2500” and have a
maximum working pressure of 275psig.
Line Stopper Fittings “Low Pressure” (H-17190):
For steel pipelines 2” to 4” in diameter, low pressure stopper fittings (half pressure control
fittings), weld type, may be used to stop the flow of gas.
Line Stopper Fittings “Full Encirclement”:
For steel pipelines 2” to 12” in diameter, full encirclement pressure control fittings may be used to
stop the flow of gas. Line stopper, Bottom-out, or Side-out fittings may be used for pipeline
connections to control flow.
x 2” (H-17155, H-17160)
x 2-1/2” (H-17155, H-17160)
x 3” to 12” (H-17255, H-17260, H-17355)
Markings: Gas line stopper fittings shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of a
16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with standardized
encoding of pipe specifications as described in the referenced Standard.
Approved Manufacturer: The City of Palo Alto approved steel line stopper fitting manufacturer
is Mueller Co. – Gas Division. Any other steel line stopper fitting manufacturer must receive prior
approval.
G. Drilling Nipples (Sav-a-Valve – H-17490): Fitting shall be forged steel and be in compliance
with the latest edition of ASTM A105 “Standard Specification for Carbon Steel Forgings for Piping
Applications” and have a maximum working pressure of 250psig.
Markings: Drilling nipples shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of a
16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with standardized
encoding of pipe specifications as described in the referenced Standard.
Approved Manufacturer: The City of Palo Alto approved steel line stopper fitting manufacturer
is Mueller Co. – Gas Division. Any other steel line stopper fitting manufacturer must receive prior
approval.
H. Casing: Casings shall be steel pipe, Schedule 40, Grade A106. Polyethylene casings shall be
high density HDPE 4710 polyethylene pipe (DR 11) with cell classification of 345464C, D or E
per ASTM D3350 “Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”.
I. Vent Pipe: Vent pipes for steel casings shall be 2-inch in diameter, Schedule 40, Grade A106
and shall terminate in a protected location, above ground, with back-to-back 90-degree elbows to
avoid water intrusion. Vent pipes for polyethylene casings shall be 2” in diameter, high density
HDPE 4710 polyethylene pipe (DR 11) with cell classification of 345464C, D or E per ASTM
D3350 “Standard Specification for Polyethylene Plastics Pipe and Fittings Materials” and shall
transition to steel schedule 40 pipe and terminate in a protected location above ground with
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back-to-back 90-degree elbows to avoid water intrusion.
J. Casing Insulators: Commercially available casing insulators with a minimum of 4 plastic
runners, each runner a minimum of 1/4" high, shall be installed at 5 feet maximum intervals on
the steel gas main prior to insertion. Insulators shall be sized to center the gas main in the
casing.
K. Cable Protectors: When inserting the pipe into the casing, the Contractor shall use a suitable
cable protector on the casing end to protect the pipe and pipe coating from damage. Cable
protectors shall be left in place after pipe insertion is completed.
L. Casing End Seals: End seals shall be Link SealTM, or approved equal, capable of forming a
watertight seal at the ends of the casing. Seamless or wrap around end seals must be used in
addition to Link SealTM to perform a watertight seal between the casing and carrier pipe.
Seamless and wrap around end seals shall be made of synthetic rubber and secured with
stainless steel banding clamps.
M. Repair Clamp: Clamp shall be used as a temporary repair only and shall not remain in service
for extended periods of time. Components should be resistant to corrosion and gaskets must be
gridded, Nitrile (Buna-N) and resistant to natural gas. The clamp shall be rated for an operating
pressure greater than the system pressure it is being installed on.
a. ¾” through 1-1/4” diameter:
i. Smith Blair Redi-Clamp model 244, full circle band with gasket.
b. 2” through 12” diameter:
i. Mueller model 220, regular gasket coverage. Bolts should be torqued to
manufacturer specifications depending on size: 2”-4” (175psig), 6”-8” (100psig), 10”-
12” (75psig).
2.03 PVC PIPE AND TUBING
This specification covers PVC pipe, tubing, and fitting for use only to maintain or repair existing PVC
gas piping. All PVC pipe, tubing, and fitting used under these specifications shall be in accordance
with the latest edition of ASTM F2817 “Standard Specification for Poly (Vinyl Chloride) (PVC) Gas
Pressure Pipe and Fittings for Maintenance or Repair.
A. Pressure Control Fittings: Fittings components shall have an alloy composition that
complies with requirements of CFR Title 49, Part 192.455(f) “External Corrosion Control:
Buried or submerged pipelines Installed after January 31, 1971”. The fitting must have a
maximum working pressure greater than the system pressure of which the fitting is to be
used on.
1. Line Stopper Fittings:
a. For PVC pipelines 2” in diameter, coated steel fittings or stainless-steel fittings may be
used if all components of the fitting are constructed of an alloy material not requiring
cathodic protection. Approved stopping system is Kleiss MCS60-2.
b. For PVC pipelines 3” to 8” in diameter, coated steel fittings or stainless-steel fittings may
be used if all components of the fitting are constructed of an alloy material not requiring
cathodic protection. Approved stopping system is Kleiss MCS60-38.
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2. Markings: Line stopper fittings shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of
a 16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with
standardized encoding of pipe specifications as described in the referenced Standard.
3. Approved Manufacturer: The City of Palo Alto approved PVC line stopper fitting
manufacturer is Kleiss. Any other steel line stopper fitting manufacturer must receive prior
approval.
2.04 WORK MATERIALS TO BE FURNISHED BY THE CITY
The City will provide all gas meters, regulators, and pipe nipples and fittings required to connect the
gas meter to the new riser.
2.05 WORK MATERIALS TO BE FURNISHED BY THE CONTRACTOR
Work materials supplied by the Contractor shall include but not be limited to:
A. All materials, equipment and appurtenances needed to complete installation of new PE mains
and services.
B. Expendable Concrete Materials: Materials required to install and finish Portland cement
concrete, such as form lumber, tie-wire, nails, etc.
C. Concrete: All Portland cement concrete including reinforcing steel, wire mesh, etc.
D. Temporary and Permanent Fencing: All fencing including traffic barricades required to provide a
barrier between vehicular/pedestrian movements and excavations.
E. Trench Backfill Sand: All backfill sand shall be clean imported sand, rock and salt free. Bay
sand shall not be accepted.
F. Paving Material: All materials required for temporary and permanent street repairs including
base materials.
G. Landscaping Materials: All landscaping materials, irrigation, plants and surface materials that are
damaged due to this Work.
H. Traffic Control Materials: All materials required to direct vehicular/pedestrian traffic including
striping, loop detectors, reflectors, etc. that may be damaged by the Work.
I. Drilling fluids and bentonite for direction drilling operations.
J. Non-skid trench plates.
K. Project notifications signs.
2.06 MANUFACTURER'S TESTING
A. Minimum burst pressure tests, conducted in accordance with the latest editions of ASTM D1599
“Standard Test Method for Resistance to Short-Time Hydraulic Pressure of Plastic Pipe, Tubing
and Fittings” and ASTM D2290 “Standard Test Method for Apparent Hoop Tensile Strength of
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Plastic or Reinforced Plastic Pipe”, and as incorporated in ASTM D2513-09a “Standard
Specification for Polyethylene (PE) Gas Pressure Pipe, Tubing and Fittings”, shall be performed
by the manufacturer to determine the short term rupture strength of the pipe and fittings
furnished. The minimum short term burst pressure shall be that required to develop a minimum
tensile strength value at yield of 2520 psi. This test shall be performed on each lot of pipe
ordered, and the manufacturer shall provide all test data as requested by the City. A lot shall
mean all material covered by a single item on a City order. Fittings shall be tested at the
frequency specified in the latest edition of ASTM D2513 “Standard Specification for Polyethylene
(PE) Gas Pressure Pipe, Tubing and Fittings”, Annex A1.
B. Sustained pressure tests shall be performed to ensure that the pipe and fittings supplied have
passed the sustained pressure test outlined in the latest edition of ASTM D1598 “Standard Test
Method for Time-to-Failure of Plastic Pipe Under Constant Internal Pressure”. The minimum
sustained pressure shall be that required to produce a minimum hoop stress value of 1320 psi.
Testing frequency shall meet or exceed that called for in ASTM D2513-09a “Standard
Specification for Polyethylene (PE) Gas Pressure Pipe, Tubing and Fittings”, Annex A1.
Manufacturer shall provide test data for each lot of pipe and/or fittings ordered as requested by
the City.
C. Polyethylene Fusion Joints (Butt and Electrofusion): All joint integrity qualification tests shall
be performed by the manufacturer in accordance with the requirements of CFR Title 49, Part
192.281 (c) (1) and (3) “Plastic Pipe” and Part 192.283 (a) (1) (i) and (iii) “Qualifying Joining
Procedures”.
D. Mechanical Plastic Joints: All joint integrity qualification tests shall be performed by the
manufacturer in accordance with the requirements of CFR Title 49, Part 192.281 (e) “Plastic
Pipe” and 192.283 (b) “Qualifying Joining Procedures”.
E. Solvent Cement (PVC Repair Only): All joint integrity qualification tests shall be performed by
the manufacturer in accordance with the requirements of CFR Title 49, Part 192.281 (b) “Plastic
Pipe” and 192.283 (a) “Qualifying Joining Procedures”.
2.07 SUBMITTALS AND QUALITY CONTROL
A. The manufacturer shall submit to the City a written quality control procedure conforming to the
latest edition of ASTM D2513 “Standard Specification for Polyethylene (PE) Gas Pressure Pipe,
Tubing and Fittings”, Annex A1, or as required by CFR Title 49, Part 192.283 “Plastic Pipe” and
192.283 “Qualifying Joining Procedures”, which shall be subject to approval by the City.
B. The manufacturer shall permit City representatives to tour extrusion facilities for the purpose of
evaluating manufacturer's capabilities. The tour shall be done during extrusion of a City order, or
if prior to order placement during the extrusion of a similar material.
C. The manufacturer shall certify that the plastic pipe and or fittings supplied to meet all the
requirements of this Specification. When requested by the City, the Manufacturer shall supply
certification for all items ordered; failure to do so shall be cause for order rejection.
2.08 INSPECTION
The City reserves the right to inspect each order upon delivery and, at the option of the City, reject
any items not meeting this Specification.
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PART 3 – EXECUTION
3.01 POLYETHYLENE PIPE INSTALLATION – GAS MAINS
A. Minimum Cover: Gas mains shall be installed with a minimum cover of 30", as measured
vertically from the top of pipe to the top of pavement.
B. Underground Clearance: Unless otherwise specified, a minimum of 12 inches vertically and 48
inches horizontally, unless a reduced separation is approved by Engineering, shall be maintained
between the pipe surface and other utility lines or adjacent foreign structures. If it is not possible
to maintain required vertical clearance from other structures, the Contractor shall receive prior
approval or case the gas main in steel pipe or concrete at the discretion of the City's
representative.
C. Gas Pipe Bedding: Trench shall be free of debris, sharp rocks, etc. before adding the sand bed
for the new gas main. Sandbed shall have a minimum thickness of 4" below and 12” above the
gas main.
D. Tracer Wire Connections: One tracer wire shall be installed with each section of Polyethylene
pipe. All tracer wire connections shall be made with the Nicotap T-102-D lateral splice sleeve
wrapped with 3M Scotch-Seal Mastic Tape Compound 2229 and electrical tape. All Nicotap
fittings must be installed with tooling specified by the manufacturer; the use of pliers or other
crimping devices will not be allowed. Tracer wires from the four pipelines feeding into an
intersection will be terminated at an anode box located by the “northerly” valve. Tracer wire shall
have knots tied in the wire as follows: north wire - no knot attached to terminal 1 of the anode
box; east wire - one knot attached to terminal 2; south wire - two knots attached to terminal 3;
west wire - three knots attached to terminal 4. Each wire shall extend a minimum five feet above
grade. The Drawings detail installation requirements. Tracer wires from steel gas mains inserted
into casings shall be extended to the closest “westerly” anode box with four knots tied.
E. Valves: Valves shall be installed at the marked locations. Valve supports are required for 2"
valves only. Valves shall be installed with the operating nut on top, facing vertically up. The City
will not accept valves that are cocked or oriented in any direction except up.
F. Anode Boxes: Anode boxes shall be installed at locations shown on plans or as directed by the
City Inspector. Anode boxes shall be installed in the same manner as valve boxes.
G. Pressure Test: The Contractor will conduct air pressure tests at 100 psig on the newly installed
system, including all main and service lines, for a minimum time of 25 hours. The City will provide
a pressure chart recorder to document all air tests. The pressure shall not decrease during the
test period. A digital gauge shall be supplied by the Contractor at a separate location to record
pressure at the start and end of pressure test. Tests shall be performed on each block of main
installed after service installation is completed.
H. Boring: All underground utilities shall be located and potholed prior to the start of boring. One
tracer wire shall be attached to all pipe prior to insertion into the bore hole. All pipe ends shall be
sealed with a butt fusion end cap or similar fitting prior to pulling into a bore hole.
I. Sealing Installed Piping: Contractor shall seal open piping with butt fusion end caps at the end
of each workday. No open pipe ends will be allowed.
3.02 GAS SERVICE (INSERTION INTO EXISTING PIPE)
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When inserting a PE pipe into an existing (abandoned) pipe, the Contractor shall follow the
procedures listed below to minimize gas service disruption:
A. Ensure ends of steel casing are free from debris that may damage the PE pipe.
B. Install new 1” PE service by pushing the new PE pipe through casing by hand.
C. Install new riser and connect new 1”PE service to main.
D. Pressure test the entire length of inserted pipe, fittings, and appurtenances for a minimum period
of 24 hours at a minimum pressure of 100 psig with air.
E. Perform all required house plumbing modifications.
Inserting new PE pipe into an existing (abandoned) pipe is not a typical installation method performed
on the City of Palo Alto natural gas distribution system and approval must be granted prior to
insertion.
3.03 GAS HOUSE LINES
All materials and installation methods must comply with the latest City adopted version of Uniform
Plumbing Code.
3.04 INSTALLATION – GAS SERVICES
A. Tapping Tee Installation
1. Contractor shall install tapping tees at the locations marked by the City. Bell holes shall be
excavated, if installing the gas mains by boring methods, at each tapping tee installation site
to provide an adequate work area for installation and inspection of tapping tees. The tapping
tees shall be installed in accordance with Section 2500 by the person(s) qualified by the City
to install tapping tees. Tapping tee fusions must be conducted in the presence of, or with the
prior approval of, the City Inspector. TAPPING TEES SHALL ONLY BE INSTALLED ON
THE TOP OF THE GAS MAIN.
2. The main shall be tapped after the tapping tee outlet coupling has cooled for the time period
specified in Section 2500 and the service line has been soaped and pressure tested. The
manufacturer supplied tapping wrench or fitting shall be the only tool used for turning the
tapping tee cutter to avoid tapping the backside of the main or loss of the cutter into the
main. Allen wrenches shall not be used.
3. Tapping tee cutter shall be moved back to the top of the tee tower prior to seal cap
installation.
B. Service Pipe Installation with Excess Flow Valves
1. All services must be installed with boring type devices, approved by the Engineer, except in
cases where ground conditions or existing underground utility congestion precludes it. Open
cut trenching of services must be approved by the Engineer.
2. Excess flow valves shall be installed on all service lines, where commercially available, as
close as practical to the tapping tee, connected by electrofusion couplings. Care shall be
taken to ensure that the excess flow valve is installed with the arrow pointing towards the
riser (away from the tapping tee).
3. For 1” services, a 1" cap shall be attached in accordance with Section 2500 by a qualified
person(s) and in the presence of, or with the prior approval of, the City's Inspector, to the end
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of the 1" service pipe, and tracer wire attached to the service pipe prior to inserting the pipe
into the bore hole. Services shall be one continuous polyethylene pipe with no fusion joints.
4. For 2” services, a 2” cap shall be attached in accordance with Section 2500 by a qualified
person(s) and in the presence of, or with the prior approval of, the City’s Inspector, to the end
of the 2” service pipe, and tracer wire attached to the service pipe prior to inserting the pipe
into the bore hole. Services shall be one continuous polyethylene pipe with no fusion joints.
Contractor shall also install 2” inline ball valve as close to the outlet of the tapping tee as
possible.
5. A qualified person shall make all connections between the excess flow valve and the service
line by electrofusion couplings in accordance with Section 2500 and in the presence of, or
with the prior approval of, the City's Inspector.
6. A qualified person shall connect by electrofusion the service line to the service riser in
accordance Section 2500 and in the presence of, or with the prior approval of, the City's
Inspector.
7. The Contractor shall install a meter valve, by-pass assembly (if indicated on construction
drawings), and end plug on each service riser. Stop cock shall be installed with operating
shut off nut facing away from structure (or facing the opening of the curb meter vault lid) with
the regulator at its left side per City Standard Specification and Details.
8. The location of all gas services shall be marked by a delta symbol, 2” in height, impressed or
chiseled to a depth of ¼” into the curb (or sidewalk if no curb line). The base of the delta
shall be parallel to the street (or curb) and its vertex shall be located on the gas service line,
pointed toward the structure in the direction of the gas meter. The marking must be placed at
the time of service installation by attaching a line locator device to the tracer wire to ensure
that the marking is located directly above the service. All old gas markings shall be removed
prior to installation of new gas meter.
9. House line: When required, Contractor must apply for plumbing permits and coordinate
approval of houseline pressure test with Building. All materials and installation methods
must comply with the latest City adopted version of the Uniform Plumbing Code.
C. Minimum Cover: Gas services shall be installed with 24" minimum cover, as measured vertically
from top of pipe to top of pavement or below existing grade.
D. Maximum Cover: Gas services shall not be installed any deeper than 42" below existing grade
unless directed by the Engineer.
E. Service Leak Testing: Prior to tapping the main, the contractor shall conduct air pressure tests,
in the presence of qualified City staff, at 100 psig on all service lines for a minimum of 15 minutes
using a digital gauge. The pressure shall not decrease during the test period. Air pressure shall
be held until after soap testing is complete. Soap test the service connection by brushing a liquid
soap and water solution around the tapping tee base at the main, both ends of the outlet
coupling, the outlet connection of the excess flow valve, the pipe to riser connection in the
customer’s yard, and at the meter valve inlet and outlet. If any leaks appear, the City’s Inspector
will direct repair procedures.
F. Surface Restoration: Once the City’s Inspector has noted the location of the service pipe in the
customer’s property, the Contractor shall restore the customer’s surface improvements to the
preconstruction condition.
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3.05 STEEL PIPE INSTALLATION
A. Welding: All steel gas carrier pipe shall be welded in accordance with CFR Title 49, Part 192,
Subpart E “Welding of Steel in Pipelines”, by a welder qualified under Section 192.227
“Qualification of Welders and Welder Operators”, and certified by the City.
B. Wrapping of Welds: Primer (Royston Roybond 747, or approved equal) and a 30-mil minimum
thickness wrapping tape shall be applied over welded joints and any other bare metal surface of
the pipe. Complete wrap shall be two (2) thicknesses of cold wrap tape covering the metal in all
places (50% overlap of the cold wrap tape) and overlapping the plant coat wrap by a minimum of
2”. Manufacturer’s primer shall not be applied to polyethylene pipe.
3.06 SYSTEM PRESSURE TEST
The Contractor will conduct an air pressure test at 100 psig on all newly installed pipelines, including
services and mains, for a minimum time of 25 hours. Test shall only be performed Monday-Thursday.
The City will provide a pressure chart recorder to document the system air test. A digital gauge shall
be supplied by the Contractor at a separate location to record pressure at the start and end of
pressure test. The pressure shall not decrease during the test period.
For pressure testing newly installed service pipelines on ABS or PVC gas mains, a separate pressure
test for a minimum of 15 minutes at a minimum of 50psig shall be performed for the service
connection tee only. All other PE service piping shall be pressure tested at a minimum of 15 minutes
at a minimum of 100psig.
All customer piping shall be inspected and approved by the building department inspector before gas
service will be instituted. Gas meters will be installed within ten working days after the building
inspector approved the building gas piping and releases a set tag for the gas meters to the Utilities
Department.
3.07 OPERATOR QUALIFICATION REQUIREMENTS
A. General Conditions: The Contractor shall have qualified persons to perform covered tasks on
the project, including polyethylene pipe joining as per Section 2500 of these standards and CFR
Title 49, Part 192, Subpart F “Joining of Materials Other Than by Welding”.
B. Qualification Testing: The Contractor shall secure a software license with Industrial Training
Services (ITS) to test and maintain Operator Qualifications (OQ) for each employee assigned to
perform covered tasks on City of Palo Alto gas projects. The Contractor shall provide the City
OQ Administrator access to Contractor’s system, for retrieval of documentation on qualified
Contractor employees.
Operator testing and qualification is required for all Contractor employees performing covered
tasks on City of Palo Alto natural gas pipelines. Individual employee will be deemed the qualified
person and shall only perform the individual task they are qualified for. The City does not
recognize span of control for Contractor personnel. The Contractor will perform the qualification
testing using their own equipment and materials, equipment for qualifying shall be the same
equipment used on the project, and all testing shall be done at the Contractors expense. At the
discretion of the City, the Contractor may be required to obtain qualification through the City or
with a City approved ITS third-party evaluator. Contractor will be required to successfully
complete the training and written exam for each task and exam may be proctored by Contractor’s
approved ITS evaluator. Contractor must perform the hands-on exam with the City or with a City
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approved ITS third-party evaluator. Contractor will be responsible for all labor, material, and
travel cost required to build props or stations and test, regardless of where the testing is located
(Contractors facility or offsite).
At a minimum, all fusion equipment used must be inspected by the City and receive a
certification sticker. The certified equipment must be used to obtain Operator Qualification fusion
certification and be used to perform fusions on the project. All testing and certifications must be
coordinated with the WGW Project Manager a minimum of three weeks in advance.
Below are the minimum required Operator Qualification tasks assigned to all contractors
performing work on City of Palo Alto natural gas pipelines:
x F01.1.0721 – Joining of Pipe: Threaded Joints
x F01.1.0761 – Butt Heat Fusion (Hydraulic)
x F01.4.0781 – Electrofusion
x G01.0981 – Backfilling
x G01.1321 – Damage Prevention During Excavation Activities
x G02.0641 – Visually Inspect Pipe and Components Prior to Installation
x G02.0901 – Installation of Plastic Pipe in a Ditch
x G02.0941 – Install Tracer Wire
x G04.0911 – Installation of Plastic Pipe in a Bore
x I07.0051 – Installation of Exothermic Electrical Connections
x L01.a.1101 – Tapping a Pipeline with a Built in Cutter
x M08.0201 – Visual Inspection of Installed Pipe and Components for Mechanical Damage
x M08.0211 – Measure and Characterize Mechanical Damage on Installed Pipe and
Components
Polyethylene fusion requirements are addressed in full detail in Section 2300 and Section 2500
of these Specifications.
The City reserves the right to add additional qualification testing based on the work being
performed. It is the responsibility of the Contractor to request what, if any, additional qualification
testing may be required.
3.08 ABANDONMENT OF NATURAL GAS FACILITIES
A. MAINS
The City’s Water-Gas-Wastewater Operations shall perform the abandonment of the natural gas
mains after the new gas main and service pipelines meet pressure tests outlined in 3.01 and 3.06
of Section 2685. The Contractor shall notify the Engineer five (5) days in advance of the pressure
test to schedule the abandonment of the natural gas main and services.
B. SERVICES AND SERVICE RISERS
Where a new gas service is to be installed or a service reconnection is to be performed, the
City’s Water-Gas-Wastewater Operations shall cut and cap the old service near the gas main or
the reconnection point after the new gas service meets the pressure tests outlined in 3.01 and
3.06 of Section 2685.
On gas services abandoned by Water-Gas-Wastewater Operations, the Contractor shall verify
the presence of gas by opening the meter valve to ensure the service is inactive and there is no
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potential hazard for combustion. After verification, the Contractor shall proceed to cut the riser
flush to grade and restore the disturbed surface to match existing.
C. VALVES
The Contractor shall perform the abandonment of valves on distribution pipelines that are
inactive and disconnected from the distribution system. The Contractor shall remove the valve
box lid and cover and restore the surface to match existing.
3.09 DESIGN STANDARDS
Polyethylene piping (medium density PE 2708) is currently the only material installed in the City’s
natural gas distribution system (except at the locations where repair work is done on steel and/or
PVC segments of the natural gas distribution system).
A. LOCATION
1. Gas mains shall be located two (2) feet off the lip of gutter on the north and east side of
streets, unless otherwise specified on the Project Drawings. Gas mains shall be twenty-four
(24) inches minimum from any parallel utility line, or as determined by the City. Gas mains
and services shall have a minimum of one (1) foot vertical clearance from any crossing utility
lines or other underground facilities.
2. Gas services shall be installed perpendicular from the gas main in the shortest straight line to
the gas meter location.
3. Above ground gas meters shall be installed on private property adjacent to the building. Curb
meter installations shall only be allowed with prior approval of the Engineer. The meter
location and installation shall be as specified on the project documents.
4. No meter or regulator shall be installed inside of a building, garage, carport, crawlspace, or in
any other enclosed area with walls on more than two sides or under a roof structure. The
Owner is responsible for installing a concrete meter pad, concrete walkway for meter access,
and bollards as required by the City.
B. DEPTH OF PIPE: Minimum depths are to be provided to the finished street surfaces, unless
otherwise specified on the Drawings.
1. The depth of new gas mains shall be installed with a minimum cover of 30”, as measured
vertically from the top of pipe to the top of pavement.
2. The depth of new gas services shall be installed with a minimum cover of 24”, as measured
vertically from the top of pipe to the top of pavement.
3. If it is not possible to maintain the above minimum cover depth requirements for new gas
mains or services, City Engineering must approve additional protection devices to be
installed that adequately prevent damage to the pipe by external forces (steel plate, casing
or concrete cap).
C. MINIMUM SIZE OF NEW MAINS AND SERVICES: The minimum new gas main size is 2”
(minimum wall thickness = 0.216”, SDR 11.0). The minimum service size for new construction is
1” (minimum wall thickness = 0.099”)
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D. VALVES: Four valves shall be installed at each intersection and three valves shall be installed at
each tee (at the property line extensions as shown on Figure 3), or as shown on the construction
drawings or as directed/approved by the Engineer.
Figure 3
Install 3 valves at each gas main tee
Install 4 valves at each gas main intersection
A 2” inline ball valve will be required on all gas services 2” and larger (as shown on Figure 4).
Placement of valve shall be as close to the tapping tee as practical.
Figure 4
E. LOAD: The maximum connected load shall be used for design purposes (the total shown on the
submitted load sheet plus any anticipated future load when available). Coincidence or diversity
factors shall not be used when designing gas services.
F. CALCULATING SERVICE SIZE: The sizing of gas services shall be based on the High-Pressure
Mueller Equation (applicable for 1 psi and greater) where the length of the service is doubled to
account for fittings and a factor of safety.
Note: the absolute pressure (psia) must be used when performing calculations with the Modified
High-Pressure Mueller Equation. The standard barometric pressure correction is 14.7 psia.
G. AVAILABLE PRESSURE
The typical pressure in the City’s natural gas distribution system is approximately 20 psig. The
City’s standard delivery pressure is 7" w.c. (water column). Non-standard delivery pressures
above 7" w.c. will be limited to 14” w.c., and 1, 2, 3 and 5 psig. Approval from the Engineering
Manager is required for any delivery pressures greater than 7" w.c. For sizing:
1. Residential gas services: The pressure at the main is assumed to be 10 psig, and the
pressure at the meter set riser shall be assumed to be 8 psig, or as noted on the individual
Gas Meter Set Standard Drawings. The services shall be sized based on the calculated head
loss between the main and the riser. If the head loss is too great, then the service size shall
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be increased.
2. Commercial/Industrial Services: The minimum required pressure upstream of the regulator,
and pressure loss through the riser, meter valve, and filter (if applicable), or as specified in
the notes on the individual Gas Meter Set Standard Drawings, shall be considered in the
design of the service. After calculating the minimum pressure required at the meter set riser,
the service shall be sized by calculating the head loss and comparing the calculated
pressure at the main to the available pressure as projected by the Gas Model. If the head
loss is too great, then the service size shall be increased.
PART 4 - NATURAL GAS HOUSE PLUMBING
Part 4 is only for City gas main replacement projects (CIP work) where the gas meter needs to be relocated
as part of the CIP. Any other gas house plumbing (any piping downstream of the gas meter) is the sole
responsibility of the property owner.
4.01 DESCRIPTION
The work to be performed shall consist of furnishing all tools, equipment, materials, supplies,
manufactured articles, transportation and services (including fuel, power, and essential
communication), labor, and other operations necessary for the modification of existing natural gas
house plumbing to accommodate relocation of gas meters including: obtaining required permits,
installation of new house gas pipes, new shut off valves and flexes, subsequent pressure testing of
the entire house gas plumbing system, and passing required inspections for houses located in Palo
Alto, for the City of Palo Alto. The work shall be complete and performed in strict accordance with the
Contract Specifications, and in compliance with all applicable codes and standards. All work,
materials and services not expressly shown or called for in the Contract Documents, which may be
necessary for the complete and proper construction of the Work, shall be performed, furnished, and
installed by the Contractor at no increase in cost to the City.
4.02 QUALIFICATIONS OF WORKMEN
Journeyman plumbers shall be licensed plumbers completely familiar with the design and application
of the work described.
4.03 MANUFACTURER'S RECOMMENDATIONS.
All equipment, materials, devices, etc., shall be installed in a manner meeting the manufacturer's
recommendations for the particular item. Prior to the start of work, the Contractor shall obtain and
deliver copies to the Engineer of all installation manuals, brochures and procedures that the
manufacturer issues for the items supplied. The Contractor shall be held responsible for all
installation’s contrary to the manufacturer's recommendations, unless otherwise approved by the
Engineer. If any item or piece of equipment or material is found to be installed not in accordance with
the manufacturer's recommendations, or as otherwise directed by the Engineer, the Contractor shall
make all necessary changes and revisions to achieve such compliance, at the Contractor's expense.
4.04 EXISTING GAS PLUMBING
The modification of the existing gas plumbing shall be performed by the contractor only after
receiving written approval from the Engineer. With the Engineer's authorization, the Contractor shall
perform all repairs and modifications required for code compliance of existing customer owned
natural gas plumbing. The Contractor shall remove and dispose of all abandoned gas plumbing
materials. The Contractor shall not modify the existing gas plumbing until the City’s Inspector verifies
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the new stub out location.
4.05 TESTING OF CUSTOMER OWNED GAS PIPING
When required, Contractor must apply and pay for all plumbing permits, testing and retesting required
showing compliance with the Contract Documents, Codes, Regulations, and all other applicable laws.
Meter sets will not be installed until all testing has been completed and the Building Department
Inspector approves the houseline work.
A. SYSTEM PRESSURE TEST: The Contractor will conduct an air pressure test in accordance with
the latest adopted version of the Uniform Plumbing Code and as required by the City’s Building
Department Inspector. The pressure shall not decrease during the test. Other inspections and
tests required by the City Building Inspector, codes, ordinances, or other legally constituted
authority, shall be the responsibility of and paid for by the Contractor. Testing of the existing gas
house plumbing shall be performed prior to connecting the new supply line.
B. TESTING: Testing will be in accordance with the City’s Building Department requirements.
C. CONTRACTOR'S CONVENIENCE TESTING: Costs associated with inspection and testing
performed exclusively for the Contractor's convenience shall be the sole responsibility of the
Contractor.
D. SCHEDULE FOR TESTING
1. Testing shall be scheduled with the Building Department in advance.
2. At least 48 hours’ notice shall be provided to the Engineer when testing is required.
3. Testing that involves City personnel shall not be scheduled on Fridays.
4.06 COOPERATION WITH THE BUILDING DEPARTMENT
City building inspectors shall have access to the Work at all times and in all locations where the Work
is in progress. Contractor shall provide such access to enable the Building Department to perform its
functions properly.
A. Revising schedule: When changes of construction schedule are necessary during construction,
Contractor shall coordinate all such changes with the Building Department.
B. Adherence to Schedule: When the Building Department is ready to inspect but is prevented
due to incompleteness of the Work, all extra charges for testing attributable to the delay will be
back charged to the Contractor and shall not be borne by the City.
4.07 COORDINATION WITH CUSTOMERS
The Contractor is responsible for coordinating access to private property with the homeowners. The
Contractor shall notify the property owner/ resident at least 7 days and again 24 hours in advance of
performing work. Prior to starting work at a specific location, the Contractor shall schedule the work
with the homeowner or resident, as the customer’s presence during the work is required.
City Operations staff shall relight all pilot lights the same day (before 5:00 P.M.) after the City installs
the new gas meter and regulator. No residence shall be left out of service overnight. Each residence
shall be reconnected, and all pilot lights relit before 5:00 P.M. each day.
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4.08 RESTORATION
The contractor shall restore all existing improvements and landscaping at each location to the pre-
construction condition as soon as practical, after completing the work at each house location, but in
no case later than one (1) week after Work is complete. The Contractor shall include restoration in
the appropriate bid items; no separate payment will be made for restoration.
END OF SECTION
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SECTION 2730
WASTEWATER DESIGN AND CONSTRUCTION STANDARDS
1.01 WASTEWATER FLOW DESIGN
A. General: A capacity study report prepared by a licensed Engineer shall be submitted to the City
of Palo Alto Utilities Engineering Department by the project’s Engineer when design (or permit)
plans are submitted for review. The report shall provide the following information for the study
area:
1. For new development connections, flow monitoring data and hydraulic analysis of the
sewage drainage basin shall be submitted to assess the new connection’s impacts on the
hydraulic characteristics of the downstream pipes within the drainage basin.
2. Pipe information for each new sanitary sewer segment, including pipe diameter, slope, invert
elevations, length, roughness coefficient for Manning’s equation, design capacity, full pipe
capacity, design flow, percentage of full pipe capacity utilized (calculated by dividing the
design flow by the full pipe capacity and multiplying by 100), and pump station operation
parameters (if applicable).
3. Land use information for conditions prior to commencement of project, immediately after
completion of project, and at build-out, including category of land use, number and type of
residential dwelling units, square footage for commercial/industrial users, square footage for
industries with unusually high water requirements, number of students (for schools), and
sewer acreage.
4. Map showing location of new sewer segments (and pump stations, if applicable), proposed
connection point(s) to existing City sewers, and location of residential/commercial/industrial
users.
B. Design: Sewer segments shall be designed for a design flow 20 years from the current year. The
Design Flow (DF) for a sewer segment is composed of three components: Peak Base
Wastewater Flow (PBWF), Groundwater Infiltration (GWI), and Rainfall-Dependent Inflow (RDI).
The Design Flow shall be based on the greater of the following two formulas:
DF = (PBWF x 0.75) + GWI + RDI
DF = PBWF + GWI
Exception: If the wastewater flow is pumped, design flows downstream of the pump station shall
be based on the maximum capacity of the pump(s).
1. Peak Base Wastewater Flow (PBWF): Average base wastewater flow (ABWF) is the
average daily dry weather flow contributed from residential, commercial, and industrial users.
ABWF is calculated using unit flow rates in Table 1-1. If supporting data indicates the need,
a higher unit flow rate should be applied for commercial/industrial users. The calculated
ABWF values must be multiplied by a Peaking Factor to account for the variations that occur
hour-to-hour and day-to-day.
PBWF = ABWF x Peaking Factor
Peaking Factor = 3.15 x ABWF -0.104
where ABWF is in million gallons per day (mgd). The Peaking Factor has a maximum of 4.0
and a minimum of 1.0.
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2. Groundwater Infiltration (GWI): Groundwater infiltration is groundwater that enters the
collection system from defects in the pipes, pipe joints, and sewer structures. The amount of
GWI entering the collection system depends on the structural condition of the system, the
depth of the pipes, and the elevation of the groundwater table relative to the elevation of the
sewer pipes. GWI tends to decrease during the dry-weather seasons and gradually
increases as the wet-weather season progresses. GWI is calculated by applying the GWI
unit flow rate that corresponds to the tributary area. GWI unit flow rate is shown in Table 1-1.
3. Rainfall-Dependent Inflow (RDI): Rainfall-Dependent Inflow is storm water that enters the
collection system in direct response to the intensity and duration of individual rainfall events.
In addition to being dependent on rainfall events, RDI is sensitive to soil moisture, increasing
throughout the wet-weather season as the soil moisture increases. A 20-year storm event
shall be used to determine estimated RDI for new sewers. RDI is calculated by applying the
RDI unit flow rate that corresponds to the tributary area. RDI unit flow rate is shown in Table
1-1.
Table 1-1 Unit Flow Rates for ABWF, GWI, and RDI*
Average Base Wastewater Flow (ABWF)
Unit Flow Rate
Land Use Category Land Use Designation** Unit (gpd/unit)
Residential
Single Family SF Dwelling Unit 220
Multi-Family MF Dwelling Unit 160
Transit-Oriented CC Dwelling Unit 160
Commercial CS, CN, CH Building Sq. Ft. 0.15
Research/Office Park RO Building Sq. Ft. 0.10
Light Industrial LI Building Sq. Ft. 0.10
Major Institutional MISP Building Sq. Ft. 0.15
School S Student 15
Groundwater Infiltration (GWI) = 500 gpd/acre
Rainfall-Dependent Inflow (RDI) = 1,900 gpd/acre
* All rates are based on the 2004 Wastewater Collection System Master Plan.
** Land Use Designations based on Palo Alto’s Planning Land Use Designations.
1.02 PIPE CAPACITY
The theoretical capacity of new pipes shall be calculated using Manning’s equation. The "n" value
(Manning's roughness coefficient) shall be equal to 0.009 for all HDPE sewer pipes.
Manning’s Equation:
Q (cfs) = (1.49 / n) x A x Rh2/3 x S½
Q = Flow (cfs)
n = Manning's roughness coefficient
A = Flow Area (ft2)
Rh = Hydraulic Radius (ft)
S = Slope (ft/ft)
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1.03 PIPE SIZE, SLOPE, DEPTH, AND ALIGNMENT
A. Pipe Size: Pipes less than or equal to 10 inches in diameter shall be sized to handle peak flows
at 75% of full pipe capacity. Pipes greater than 10 inches in diameter shall be sized to handle
peak flows at 90% of full pipe capacity. The diameter for gravity sewer mains shall be 8-inches
or larger while sewer laterals shall be 4-inches but no larger than 6-inches. A sewer lateral larger
than 6-inches serving a private property shall be considered a private main, even if it crosses the
City’s right-of-way. When a smaller sewer pipe joins a large one, the top of both pipes (crowns)
should be at the same elevation.
B. Slope: All sewers shall be designed and constructed to give a mean velocity, when flowing full,
of not less than 2 feet per second. The following are the minimum slopes that should be
provided for each sanitary sewer segment:
Sewer Size Minimum Slope (Feet per 100 Feet)
4 inch (laterals) 2.00
6 inch (laterals) 1.00
8 inch 0.34
10 inch 0.25
12 inch 0.19
15 inch 0.14
18 inch 0.11
21 inch 0.09
24 inch 0.08
27 inch 0.07
30 inch 0.06
36 inch 0.04
42 inch 0.04
Where velocities greater than fifteen (15) feet per second are attained, special provisions shall be
made to protect against displacement by erosion, shock, and hydraulic jumps at changes in
velocity.
Sewers on 20 percent slopes or greater shall be anchored securely with concrete anchors,
spaced as follows:
1. Not over 36 feet on center for grades of 20 to 35 percent;
2. Not over 24 feet on center for grades of 35 to 50 percent;
3. Not over 16 feet on center for grades of 50 percent and over.
C. Depth: In general, sewers should be placed below pressure utilities and be sufficiently deep to
receive sewage from basement. Crown (top inside surface of the pipe) of any inlet pipe shall
not be lower than the elevation of the outlet main crown in the manhole, unless otherwise
approved by the Engineer.
D. Alignment: The horizontal and vertical alignment of sewers shall be maintained by the use of
laser survey equipment. Unless otherwise approved by the Engineer, all sewers shall be
constructed straight and at uniform grade between manholes.
1.04 WASTEWATER FLOW CONTROL/BY-PASS
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Contractor shall furnish, install, and operate pumps, plugs, conduits, temporary piping, and other
equipment to temporarily convey the sewage or to divert the flow of wastewater for pipe
replacement/rehabilitation around the sewer reach in which work is or to be performed.
A. Temporary bypass in open pits at manhole, cleanout, and lateral-connection locations:
Contractor shall maintain uninterrupted sewer service to all properties connected to the sewer
being replaced. Appropriate rigid pipe or flexible tubing shall be used, before the end of EACH
workday, to make temporary connections to convey sewage where permanent connections could
not be made at manhole, cleanout, and/or lateral to main locations. It is prohibited to leave
standing sewage overnight in manhole and cleanout excavations.
B. Flow By-Pass: It shall be the Contractor’s responsibility to provide a pumping system with
sufficient capacity to manage existing flows plus additional flow that may occur during a rain
event. The pumping system shall have automated controls. Bypassed lines larger than 18”
diameter shall automatically switch operation to the standby pumps in the event of a primary
pump failure. The Contractor shall provide personnel to observe, fuel, and maintain the bypass
pumping system at all times when it is operating. An audible alarm shall be provided to signal
high level at the bypass point.
If the City must set up flow bypass or perform bypass pumping, whether because of contractor’s
failure to set up flow bypass or to install needed pumps, the City will deduct the cost of flow bypass or
pumping from contractor’s monthly progress payments.
Temporary bypass pipe used within truck-route roadways shall be installed below the street surface
and properly plated. Plugs shall be so designed that all or any portion of the wastewater can be
released. Plugs shall be provided with a tag line.
Standby pumps and standby power shall be provided with 100 percent redundancy. If pumping is
required on a 24-hour basis in a residential or commercial area, Contractor shall get a City permit,
construct, and use a temporary power service. If pumping is required on a 24-hour basis in an
industrial area, equipment shall be sound-attenuated in a manner to keep noise to a minimum. Noise
level shall conform to the requirements of the City's noise ordinance as stated in the City of Palo Alto
Municipal Code.
Bypass pumping shall be performed in such manner as will not damage public or private property or
create a nuisance or health menace. The pumped wastewater shall be in an enclosed hose or pipe
and shall be redirected into the sanitary sewer system. It shall be adequately protected from traffic.
If applicable, the bypass hose or pipe along the sidewalk shall be covered with a ramp to protect the
pedestrians from tripping and falling. Dumping or free flow of wastewater on private property, gutters,
streets, sidewalks, or into storm sewers is prohibited. The Contractor shall not block access to
driveways, streets, or other facilities with any flow control activities.
Temporary plugging will be permitted on pipes with diameters of 6-inches or smaller. See Section
1.05, Sewage Spill Contingency Plan for monitoring the manhole upstream of the plugged pipe.
The Contractor shall be liable for all damages associated with this work, including fines imposed on
the City for spilled sewage. After the work has been completed, flow shall be restored to normal.
The Contractor shall submit a sewage bypass pumping/diversion plan to the Engineer for review as part
of the submittal process prior to the issuance of Notice to Proceed. The Contractor shall notify the
Engineer 24 hours prior to commencing the bypass pumping operation. The Contractor’s plan for
sewage bypass pumping/diversion shall be satisfactory to the Engineer before the Contractor shall be
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allowed to commence sewage bypass pumping/diversion.
Bypass pumping shall be performed in conformance with all applicable local, state and federal laws
and permits issued by jurisdictional regulatory agencies. Permits required by such agencies (e.g.,
Valley Water, SFPUC, California Department of Fish and Game, Regional Water Quality Control
Board, US Fish and Wildlife, Army Corps of Engineers) for by-pass pumping shall be obtained by the
Contractor. It is the Contractor’s responsibility, while preparing the Bid, to evaluate what permits
need to be obtained and estimate fees and anticipate lead time necessary to procure the required
permits to complete the Work. Payment of all costs and expenses for such licenses, permits, and
fees shall be included in one or more bid items. No other compensation shall be paid to the
Contractor for these items or for delays caused by non-City agencies or conditions set forth in the
licenses or permits issued by other agencies.
1.05 SEWAGE SPILL CONTINGENCY PLAN
The Contractor shall submit for Engineer’s approval a “Sewage Spill Contingency Plan” consisting of
secondary containment, diversion, and pumping capable of handling the flow rate in the subject
sewer line. The Contractor is also required to:
A. Notify the on-site inspector before any main is plugged to facilitate construction work.
B. Determine the release point* if the main should not be unplugged before an overflow occurs.
C. Require a job laborer to observe the flow and monitor the rise in elevation of the sewage in the
manhole at the release point.
D. The contractor is to notify the project inspector when the elevation of the sewage is within 1.5’ of
the rim at the release point manhole.
*Release point is the lowest point in the sewer collection system tributary to the plugged line. The
manhole rim and invert elevations, and the peak flow information, can be obtained from the Engineer.
1.06 WASTEWATER MAIN REMOVAL OR ABANDONMENT
Contractor shall plug existing sewer mains to be abandoned at the downstream locations. The
abandoned pipeline shall be monitored for a 48-hour period to ensure that there is no flow in the
existing main or laterals. Upon verification of abandoned pipe, the sewer main shall be completed
filled with CDF conforming to Water, Gas, and Wastewater Utility Standards Section 2200,2.5,
“Controlled Density Fill”. Cost of sewer main abandonment shall be included in one or more bid
items.
1.07 MANHOLES
Manholes shall be installed at the following locations: at the end of each sanitary sewer segment, at
any changes in grade, size or alignment, at all intersections, and at distances not greater than 500
feet between manholes. Greater spacing between manholes may be permitted as approved by the
Engineer.
The minimum inside diameter of manhole barrel sections shall be 48 inches. A minimum inside
diameter of 24 inches for concrete grade rings shall be provided to allow man-entry access. The flow
channel through the manhole shall be made to conform in shape and slope to that of the sanitary
sewer mains. All pipes entering the manhole shall be provided with a water stop within 12 inches of
the edge of the concrete base.
For drop manholes, a drop pipe should be provided for a sewer main entering a manhole at an
elevation of 30 inches or more from the flow line of the manhole (refer to standard details). Where the
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difference in elevation between the incoming sewer and the top of the outlet pipe is less than 30
inches, the invert should be channeled to prevent solid deposition.
Drop manholes should be constructed with an outside drop connection. the entire outside drop
connection shall be encased in concrete.
1.08 AERIAL CROSSINGS
Support shall be provided for all joints in pipes utilized for aerial crossings. The supports shall be
designed to prevent overturning and settlement. Expansion joints shall be provided between above-
ground and below-ground sewers. The impact of flood waters and debris on the pipe shall be
considered in the design of aerial crossings.
1.09 SEWERS CROSSING STREAMS
Sewer systems shall be designed to minimize the number of stream crossings. Sewer main crossing
streams shall be installed in a casing at a sufficient depth below the natural bottom of the stream bed
to protect the sewer main. If jack and bore method is used, the design of steel casing shall be
approved by the City. If horizontal directional drilling method is used, the design shall be approved
by the City. In general, the cover requirements must be met by the permitting agency:
xx One (1) foot of cover is required where sewer pipe is located in bedrock;
x Three (3) feet of cover is required where sewer pipe is located in all other material types. In
major streams, more than three feet of cover may be required.
x In paved stream channels, the top of the sewer line should be placed a minimum of one (1) foot
below the bottom of the channel pavement.
Less cover will be approved only if the proposed sewer crossing will not interfere with future
improvements to the stream channel. Sewers located along streams shall be located outside of the
stream bed and sufficiently removed providing for future possible stream widening and to prevent
pollution by siltation during construction. Sewers crossing streams should be designed to cross the
stream as nearly perpendicular to the stream flow as possible and shall be consistent in grade.
A. Materials: Sewers entering or crossing streams shall be designed and submitted to the City for
approval. Sewers shall be constructed to remain watertight and free from changes in alignment
or grade. Material used to backfill the trench shall be stone, coarse aggregate, washed gravel, or
other materials which will not cause siltation.
B. Siltation and Erosion: Best Management Practice (BMP) methods that will minimize siltation
and erosion from the site shall be employed. The design engineer shall include in the Project
Specifications the methods(s) to be employed in the construction of sewers in or near streams to
provide adequate control of siltation and erosion. Project Specifications shall require that
cleanup, grading, seeding, and planting or restoration of all work areas shall begin immediately.
Exposed areas shall not remain unprotected for more than seven (7) days.
1.10 PROTECTION OF WATER SUPPLIES
A. Water Supply Interconnections: There shall be no physical connections between a public or
private potable water supply system and a sewer collection system, or appurtenance thereto
which would permit the passage of any sewage or polluted water into the potable supply. No
water pipe shall pass through or come in contact with any part of a sewer manhole.
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B. Storm system interconnections: There shall be no physical connections between a public or
private development storm drainage system, or appurtenance thereto which would permit the
passage of any sewage or polluted water into the storm drain system. No storm drain pipe shall
pass through or come in contact with any part of a sewer manhole.
C. Relations to Water Works Structures: Sewers shall meet the requirements of the State Water
Resources Control Board "Criteria for the Separation of Water Mains and Sanitary Sewers".
END OF SECTION
136
VITRIFIED CLAY SEWER PIPE SECTION 2731
CITY OF PALO ALTO Section 2731 PAGE 1
SECTION 2731
VITRIFIED CLAY SEWER PIPE
1.01 DESCRIPTION
This section covers the installation of new vitrified clay sewer pipe (VCP) for spot repairs to correct
condition defects such as broken pipe, pipe with sever cracks, protruding lateral, sag, offset joint,
missing pipe, etc. Pipe shall be as specified herein and installed at the locations shown on the
Drawings.
1.02 SUBMITTALS
A. The Contractor shall submit for approval by the Engineer the following information:
B. Manufacturer's literature on the materials identified below. Literature shall include recommended
installation procedures.
C. Certification by the manufacturer that all pipe and fittings furnished under this specification were
manufactured, sampled, tested, and inspected in accordance with ASTM C700 and ASTM C301.
1.03 MATERIALS
A. Vitrified Clay Pipe: ASTM C700 Extra Strength, unglazed; Bell and Spigot Type and Fittings per
ASTM C425. Gladding, McBean & Co., or approved equal.
B. Couplings: Rubber or elastomeric PVC flexible, shielded couplings with stainless steel screws,
nuts, housings, and anti-radial shear (ARC)bands. Mission Rubber Company "Calder Style
Coupling", Fernco Inc. "Shielded Coupling" or approved equal.
C. Stoppers: Vitrified Clay or Plastic.
Each length of vitrified clay pipe shall be marked with the manufacturer's name or trademark, the
location of the plant, and the words "Extra Strength" or the symbol "ES."
Wye fittings shall be furnished with spurs already securely fastened by the manufacturer to the
barrel of the pipe. There shall be no projection on the inner surface of the pipe barrel. The axis
of the spur on the fitting shall be 45-degrees from the longitudinal axis of the pipe. Tee fittings
are unacceptable.
Stoppers furnished for installation in branch fittings and ends of pipe left unconnected shall
sustain all applied construction and in-place loads, including field pressure tests.
1.04 JOINING AND INSTALLATION
Pipe and fittings shall be handled, joined, and installed in accordance with the printed instructions
and recommendations of the pipe manufacturer. Joint contact surfaces shall be cleaned immediately
prior to joining. Use joint lubricants and joining methods recommended by the pipe manufacturer.
Unless otherwise specified, lay all pipe straight between changes in alignment and at uniform grade
between changes in grade. Pipe bedding shall provide uniform and continuous support of the pipe
barrel. Excavate bell holes for each pipe joint.
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The laying of the pipe shall be in finished trenches free from water or debris. Start pipe laying at the
lowest point and install the pipe so that the spigot ends point in the direction of flow to prevent
bedding material from entering the joint. After each pipe has been brought to grade, aligned, and
placed in final position, deposit and shovel slice or spade bedding material under the pipe haunches.
No wedging or blocking to support the pipe will be permitted.
Every precaution shall be taken to prevent foreign material from entering the pipe during installation.
No debris, tools, clothing, or other materials shall be placed in the pipe. Whenever pipe laying is
stopped, the open end of the pipe shall be closed with an end board closely fitting the end of the pipe
to keep sand and earth out of the pipe. The end board shall have several small holes near the
bottom to permit water to enter the pipe and prevent flotation in the event of flooding of the trench.
When an existing VCP sewer main pipe is entering or leaving a newly constructed manhole,
Contractor shall replace in kind, a small section of new VCP pipe and connect to the existing VCP
pipe with a Anti-Radial (ARC) flexible coupling. Contractor shall remove the bell by making straight
cuts on both sides of new VCP pipe, refer to standard detail WWD-07B & 08B for specifications on
pipe length.
1.05 TESTING
The pipe shall be tested with low pressure air in accordance with ASTM C828. Wyes shall be
plugged during test. Any newly installed or replaced sewer lateral along the pipe shall also be tested
by setting the plug at the cleanout location. Tests shall be made in the presence of the Contractor
and the Engineer.
If the pipe fails the air test, the Contractor shall locate the source(s) of the leak and repair the
defect(s) or relay the pipe, as necessary. The pipe shall then be retested until a satisfactory result is
obtained.
Despite any previous testing, any leaks developed before the end of the 1-year guarantee period
shall be expeditiously repaired by the Contractor at no expense to the City.
1.06 CLEANING AND VIDEO INSPECTION
After installation, pipe and structures shall be cleaned and video inspected in accordance with the
Project Specifications and Section 2739, “Cleaning and Video Inspection of Sewer Pipe” of these
Standards. The Contractor shall repair all defects or relay the pipe, as necessary.
END OF SECTION
138
POLYVINYL CHLORIDE SEWER PIPE SECTION 2733
CITY OF PALO ALTO Section 2733 PAGE 1
SECTION 2733
POLYVINYL CHLORIDE SEWER PIPE
1.01 SCOPE
This section covers installation of new polyvinyl chloride sewer pipe (PVC) for spot repairs to match
existing pipe. Pipelines shall be as specified herein and installed at the locations shown on the
Drawings.
1.02 SUBMITTALS
The Contractor shall submit for approval by the Engineer the following information:
A. Manufacturer's literature on the materials identified below. Literature shall include recommended
installation procedures.
B. Certification by the manufacturer that all pipe and fittings furnished under this specification were
manufactured, sampled, tested, and inspected in accordance with the specified standards. The
date the pipe was manufactured shall be included in the Certification.
1.03 MATERIALS
Sewer pipe and fittings shall meet the following minimum requirements.
A. PVC Pipe & Fittings:
1. PSM SDR 26 PVC Sanitary sewer pipe that meets the requirements of ASTM D3034. Pipe
shall have elastomeric gasket joints that are oil resistant and conform to ASTM F477. (For 4
to 12 inch pipes).
2. AWWA C900, PR 200, DR 14 (for 4 to 12 inch pipes) unless noted otherwise on the
Drawings.
3. AWWA C905, PR 235, DR 18 (for 14 inch or larger pipes) unless noted otherwise on the
Drawings.
Couplings: Anti-Radial Shear “Calder-Style” flexible couplings. Flexible couplings with
mechanical clamps shall be used to connect two plain end PVC pipes of the same OD. PVC
pipe and fittings shall be manufactured in a one-piece mold with injection PVC compound
conforming to ASTM D1784, class 12454 B. Bells shall conform to ASTM D3139 as measured in
accordance with ASTM D2122 and gaskets shall conform to ASTM F477.
All PVC pipes shall be white or green. Contractors shall mark all PVC pipes with 3"-wide
(minimum) green color marking tape 12” above pipes which says ‘Sewer Pipe’ across the length
of the pipes. Each length of polyvinyl chloride pipe and each PVC fitting shall be marked with:
1. The nominal size and OD base.
2. PVC.
3. Dimension ratio number (for example, DR14).
4. The AWWA pressure class or rating (for example, PC200 or PR 200). (If applicable)
5. The AWWA designation number (for example, AWWA C900). (If applicable)
6. The manufacturer's name or trademark and production record code.
1.04 JOINING AND INSTALLATION
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Pipe and fittings shall be handled, joined, and installed in accordance with the printed instructions
and recommendations of the pipe manufacturer. Joint contact surfaces shall be cleaned immediately
prior to joining. Use joint lubricants and joining methods recommended by the pipe manufacturer.
Lubricant used for field assembly of gasketed PVC pipe shall have no detrimental effect on the
gasket, joint, fitting or pipe.
Unless otherwise specified, lay all pipe straight between changes in alignment and at uniform grade
between changes in grade. Pipe bedding shall provide uniform and continuous support of the pipe
barrel. Each length of pipe shall be laid on compacted, standard bedding material as specified and
shall have full bearing for its entire length between bell holes excavated in said bedding material to
allow for unobstructed assembly of all bell and spigot joints. Do not insert pipe past the reference
mark. Stabbing, swinging-in, or popping-on spigot ends of pipe into bell ends will not be permitted.
After jointing is accomplished, all annular spaces between pipe and bell holes shall be packed with
bedding material, taking care not to damage, move, or lift the pipe from its bedding support.
The laying of the pipe shall be in finished trenches free from water or debris. After each pipe has
been brought to grade, aligned, and placed in final position, deposit and shovel-slice or spade
bedding material under the pipe haunches. No wedging or blocking to support the pipe will be
permitted.
Every precaution shall be taken to prevent foreign material from entering the pipe during installation.
No debris, tools, clothing, or other materials shall be placed in the pipe. Whenever pipe laying is
stopped, the open end of the pipe shall be closed with an end board closely fitting the end of the pipe
to keep sand and earth out of the pipe. The end board shall have several small holes near the
bottom to permit water to enter the pipe and prevent flotation in the event of flooding of the trench.
Where the pipe connects with the outside face of a manhole wall or the wall of any other structure, a
pipe joint or coupling shall be provided a maximum of 12" from the face of the wall such that slight
flexibility or motion can take place in or near the plane of the wall face.
All PVC pipe entering or leaving a concrete structure shall have a rubber sealing gasket, as supplied
by the pipe manufacturer, firmly seated perpendicular to the pipe axis, around the pipe exterior and
cast into the structure base or centered in the manhole wall as a water stop. The water stop shall be
firmly fitted around the pipe exterior. Said water stop may also consist of a manhole coupling with
rubber sealing rings cast into the structure base.
1.05 DEFLECTION
The inside diameter of an installed section of flexible pipe shall not be allowed to deflect more than
five (5%) percent. All PVC solid wall flexible pipe shall be checked by means of a pipe deflection
gauge in the presence of the Engineer after the placement of all trench backfills, aggregate subbase
(if specified) but prior to installation of aggregate base and/or asphalt concrete. The deflection
standard will also be applied to installed pipelines prior to the expiration of the 12-month warranty
period.
The pipe deflection gauge shall be fabricated to permit passage through installed sections of
pipelines within the specified tolerances for the applicable plastic pipe and the maximum deflection
set forth herein. The pipe deflection gauge shall have at least 9 legs, and the number of legs shall be
odd. Any section or sections of plastic pipe that does not permit deflection gauge passage will not be
accepted and said section or sections shall be properly repaired or replaced and rechecked as
directed by the Engineer. Re-rounding through the use of a vibratory machine will not be permitted.
1.06 TESTING
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The installed pipe shall be tested with low pressure air in accordance with ASTM C828. Test shall be
made in the presence of the Contractor and the Engineer. If the pipe fails the air test, the Contractor
shall locate the source(s) of the leak and repair the defect(s) or relay the pipe, as necessary. The
pipe shall then be retested until a satisfactory result is obtained. Despite any previous testing, any
leaks developed before the end of the 1-year guarantee period shall be expeditiously repaired by the
Contractor at no expense to the City.
1.07 CLEANING AND VIDEO INSPECTION
After installation, pipe and structures shall be cleaned and video inspected in accordance with
Section 2739, “Cleaning and Video Inspection of Sewer Pipe.” The Contractor shall repair all defects
or relay the pipe, as necessary.
END OF SECTION
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SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 1
SECTION 2735
SEWER CONSTRUCTION WITH POLYETHYLENE PIPE
1.01 GENERAL
A. Scope: This section covers the installation of new high density polyethylene sewer pipe (HDPE)
by pipe bursting or open trench method (if applicable). Pipe shall be as specified herein and
shall be installed at the locations, and using the methods, indicated on the Drawings.
B. General Bid Requirements (for CIP Projects containing pipe bursting or open trench)
Qualifications of Bidders:
1. All sewer main installation work by open trench method shall be performed by an
experienced contractor or subcontractor who has completed at least 10,000 feet of 8-inch in
diameter or larger pipes within the last three years.
2. All sewer main installation work by pipe-bursting method shall be performed by an
experienced contractor or subcontractor who meets the following qualification:
a. The contractor or subcontractor shall have completed at least three projects in the last
five years, involving pipe-bursting installation of a combined total of 20,000 feet or more
of 8 to 22 inches (O.D. of new pipe) pipes in diameter.
b. The contractor or subcontractor shall have completed projects involving pipe-bursting
installation of a combined total of 5,000 feet or more of 24 inches (O.D. of new pipe) or
larger pipes in diameter. (Note: This requirement is only applicable for project scope
involving 24” or larger pipes.)
c. The project on-site superintendent and/or on-site foreman shall each have at least
10,000 feet and three years experience involving pipe-bursting installation on 8 inches
(O.D. of new pipe) or larger pipes. The on-site superintendent and/or on-site foreman
shall not be removed or replaced from the project without written permission from the
City. The replacement person shall also meet the required qualification.
d. The contractor shall submit the pipe-bursting operator’s certification of training by the
pipe bursting system manufacturer. The operator shall be trained in the use of the pipe
bursting equipment by an authorized representative of the manufacturer. Training shall
include handling and installation of pipe and use of equipment.
3. All sewer lateral installation work by open trench method shall be performed by an
experienced contractor or subcontractor who has completed at least 1,000 feet of 4-inch in
diameter or larger pipes within the last three years.
4. All sewer lateral installation work by pipe-bursting method shall be performed by an
experienced contractor or subcontractor who has completed at least 15,000 feet of 4-inch in
diameter or larger pipes within the last three years
The following data shall be submitted with the bid, using the City-provided form #2735-1,
for the company and staff experience with open trench construction:
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SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 2
Contractor/Subcontractor Open Trench Construction Experience
x Name of Contractor and/or Subcontractor.
x Name of project and year of construction.
x Project location and project dollar amount.
x Owner, owner contact, and phone number.
x Total footage and size of open trench construction experience as described above on 8 inch
or larger pipe.
The following data shall be submitted with the bid, using the City-provided form #2735-2,
for the staff experience with open trench construction:
On-site Superintendent and/or Foreman Open Trench Construction Experience
x Full name.
x Years of pipe-bursting experience.
x Name, location, year, owner, owner contact information of the referenced project(s).
x Total footage of open trench construction experience on 8 inch or larger pipe.
The following data shall be submitted with the bid, using the City-provided form #2735-3,
for the company experience with pipe-bursting construction:
Contractor/Subcontractor Pipe-Bursting Experience
x Name of Contractor and/or Subcontractor.
x Name of project and year of construction.
x Project location and project dollar amount.
x Owner, 2wner contact, and phone number.
x Total footage and size of pipe-bursting experience as described above for 8 to 22 inch (O.D.
of new pipe) pipe.
x Total footage and size of pipe-bursting experience as described above for 24 inch (O.D. of
new pipe) or larger pipe. (Note: This requirement is only applicable for project scope
involving 24” or larger pipes.)
The following data shall be submitted with the bid, using the City-provided form #2735-4,
for the staff experience with pipe-bursting construction:
On-site Superintendent and/or Foreman Pipe-Bursting Experience
x Full name.
x Years of pipe-bursting experience.
x Name, location, year, owner, owner contact information of the referenced project(s).
x Total footage of pipe-bursting experience on 8 inch or larger pipe.
5. Patents: The Contractor shall assume all costs arising from the use of any pipe-bursting
patented materials, equipment, devices, or processes used on or incorporated in the work,
and agrees to indemnify and save harmless the City of Palo Alto and its employees, and
their duly authorized representatives, from all suits at law, or actions of every nature for, or
on account of the use of any patented materials, equipment, devices, or processes.
The City’s purchasing manager in conjunction with the City’s project manager shall
determine whether the Contractor that is otherwise the lowest responsive bidder, meets the
experience and qualification criteria and shall notify the Contractor in writing of a
determination that it does not meet the criteria. The Contractor may dispute this
143
SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 3
determination by delivering written notice to the city’s purchasing manager within 5 business
days of receipt of the City’s notice of disqualification. The determination shall be final if the
Contractor does not submit a notice requesting a hearing within this time period. The notice
shall request a hearing and set forth the grounds on which the Contractor disputes the City’s
determination. Upon receipt of the Contractor’s notice an informal hearing shall be
scheduled with the City Manager or designee at which the Contractor will be given the
opportunity to present information and the reasons for disputing the determination that it
does not meet the qualification and experience criteria. The decision of the City Manager or
designee shall be final.
1.02 SUBMITTALS
The Contractor shall submit for approval by the Engineer the following information:
A. Manufacturer’s literature on the materials and equipment.
B. Certification by the manufacturer that all pipe and fittings furnished under this specification were
manufactured, sampled, tested, and inspected in accordance with the latest version of ASTM
F714-85 and ASTM D3350 (for cell classification). Certification shall be signed by an authorized
agent of the manufacturer. A report of test results shall be furnished if requested by the
Engineer. The date the pipe was manufactured shall be included in the Certification.
C. Pipe bursting operator’s training certification by an authorized representative of the equipment
manufacturer.
D. Fusion Certifications by City of Palo Alto – provide names and copies of cards issued to all
operators.
E. Access pit locations.
F. Access to Contractor’s Datalogger Vault.
G. Flow bypass plan, if applicable.
1.03 MATERIALS AND EQUIPMENT
Sanitary sewer materials shall meet the requirements of this section, Standard Specifications Section
2300 ‘Polyethylene Pipe Installation for Water, Gas, Wastewater’, and Standard Specifications
Section 2737 ‘Sanitary Sewer Lateral’.
A. Service Saddles: All service saddles shall be electrofusion type saddles by Central, Frialen by
Friatec, or approved equal.
B. Pipe Bursting Equipment: Equipment manufacturers have developed a vast array of different
tools and equipment to meet the wide variety of demands for pipe bursting projects. Pneumatic
and static pipe bursting are the two primary methods of pipe bursting projects performed in North
America. Contractors shall select pipe bursting equipment based on project design application,
pipe material to be installed, clearance to adjacent or crossing utilities, soil conditions, noise, risk
mitigation, etc. Static pipe bursting equipment shall be used to avoid damage where existing
underground pipes are in proximity.
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SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 4
a. Pneumatic Pipe Bursting
1. Winch Assembly
2. Pneumatic “Hammer” Pipe Bursting Tool & Expander Head
3. Air Compressor and Hose Assembly
b. Static Pipe Bursting
1. Static machine Assembly
2. Rod, Cable, chain & Expander Head
3. Series of Cutters, Splitters, or other tools placed in front of expander head
C. Pipe and Fittings: SDR-17 Extra High Molecular Weight, High Density Polyethylene PE 4710,
Cell Class PE445574C/E (inner wall shall be white or light in color) per ASTM D3350 in IPS
sizes. Performance Pipe “DriscoPlex 4600” with four (4) equally spaced green single stripes or
approved equal.
The pipe shall contain no recycled compound except that of which is generated in the
manufacturer’s own plant from resin of the same specification, from the same raw material type.
Pipe and Fittings shall be homogeneous throughout and free of:
a. Serious abrasion, cutting, or gouging of the outside surface extending to more than 10
percent of the wall thickness in depth.
b. Cracks
c. Kinking (generally due to excessive or abrupt bending)
d. Flattening
e. Holes
f. Blisters
g. Other injurious defects
Pipe and fittings shall be uniform in color, opacity, density, and other physical properties. Any
pipe and fittings not meeting these criteria shall be rejected.
The average outside diameter and wall thickness of pipe and fittings shall conform to Table 1
when measured in accordance with ASTM D2122, D3035, D3350 (cell 445574C).
TABLE 1
Nominal Size
(inches)
Nominal OD
(inches)
Minimum Wall Thickness
SDR17 (inches)
4 4.500 0.265
6 6.625 0.390
8 8.625 0.507
10 10.750 0.632
12 12.750 0.750
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SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 5
TABLE 1
Nominal Size
(inches)
Nominal OD
(inches)
Minimum Wall Thickness
SDR17 (inches)
14 14.000 0.824
16 16.000 0.941
18 18.000 1.059
20 20.000 1.176
22 22.000 1.294
24 24.000 1.412
26 26.000 1.529
28 28.000 1.647
30 30.000 1.765
32 32.000 1.882
34 34.000 2.000
36 36.000 2.118
42 42.000 2.471
D. Pipe Markings
Pipe shall be marked at 3-foot intervals or less with the manufacturer's name (or trade mark), the
designation ASTM F714 and ASTM D3350 , including the year of issue, the letters "PE" followed
by the cell classification number of the raw material compound used, the nominal pipe size in
inches, the dimensional ratio, and the manufacturer's code identifying the resin manufacturer, lot
number, and date of manufacture.
All sewer pipes shall have a white or light gray interior and have an exterior color of either black
or gray. Additionally, the exterior pipe shall be color identified by four (4) longitudinal green
stripes evenly spaced. The pipes shall be properly stored and handled in accordance with the
manufacturer’s recommendations and shall be less than two (2) years old at the time of
installation. Contractor shall factor in lead times for ordering compliant pipe to meet project
requirements.
Fittings shall be marked with the manufacturer's name (or trademark), the designation ASTM
D3350 and ASTM F714, and the manufacturer's code identifying the resin manufacturer, lot
number, and date of manufacture.
E. Electrofusion Couplings: Electrofusion couplings shall be manufactured by Friatec (Frialen
Safety Fittings). Any other electrofusion manufacturer such as Central, Kerotest (Innogaz
Electrofusion Products) or equal must receive prior approval. Electrofusion couplings to join
sewer mains shall only be used upon Engineer’s approval.
F. Other Equipment
Butt Fusion Machine: McElroy Manufacturing, Inc. or approved equal.
Electrofusion Machine: Central, Friatec, or approved equal.
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SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 6
External and Internal Bead Removers: McElroy Manufacturing, Inc. or approved equal.
Pulling or Pushing Head: Driscopipe, Plexco or approved equal.
1.04 JOINING AND INSTALLATION
Subsurface Condition: Refer to Invitation for Bid (IFB) Package Part 2 – Instructions to Bidders
Section 17.0 for subsurface condition.
A. Pipe Bursting
1. Access Pits: Access pit locations shall be chosen and recommended by the Contractor with the
intent of minimizing excavation and traffic disruption. Recommended locations shall be at
service connections, manhole construction, or at points where repairs need to be performed. The
Contractor shall submit the number, location, and size of pits to Engineer for review prior to start
of the work.
The access pits shall be excavated to allow adequate width for access of workers, sheeting and
shoring installation, and to provide clearance necessary to avoid damage to the main during
installation. Care shall be taken to protect existing utilities.
The minimum length of each access pit as measured at the bottom of trench shall be determined
by the formula, Length = (12 x Outside Diameter of the liner in feet) + (2.5 x Depth of the trench
in feet).
2. Joining: Pipes shall be joined to one another and to plastic fittings by thermal butt-fusion, in
accordance with ASTM D2657, or by automatic electrofusion. Operators of fusion equipment
must pass qualification testing by the City of Palo Alto Utilities Department prior to performing
any fusion work. Time and temperature of fusion shall be per the manufacturer's
recommendation. Weld on flanges may be used to join pipes in access pits if approved by the
Engineer. Joints shall be stronger than the pipe itself, be properly aligned, and contain no gaps
or voids. Bead projections on the inside of the pipe shall be removed. No rubber couplings are
allowed on mainlines, unless approved by the Engineer.
3. Insertion of the new pipe: The pipe shall be supported on rollers throughout its entire length
during insertion. Dragging of the pipe along the ground during insertion will not be permitted.
4. Pipe Bursting: To ensure structural integrity and reduce risk for future leaks, installation of
unnecessary electrofusion or mechanical couplings should be avoided. Accordingly, with respect
to sewer mains with upstream and downstream manholes that are within 500 linear feet apart,
the use of couplings is not allowed, unless approved by the Engineer for unavoidable
circumstances. The Contractor shall plan and schedule the pipe-bursting work to replace each
reach of sewer main from manhole to manhole completely in one working day during the work
hours. The Contractor shall schedule all pipe-bursting preparation work and adjust the bursting
speed to meet all requirements. The Contractor should include the cost to use ‘pre-burst’ or
‘double-pull’ method, if deemed necessary to successfully replace the sewer main and meet all
requirements. The use of lubricant mud to reduce the friction is allowed when hard and very
dense soil is encountered.
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SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 7
The Contractor shall also expose the main, at every lateral connection to a depth equal to 1 x the
outside diameter of the main, under the invert of the existing main to allow free movement of the
bursting head.
If there is no adequate staging area to store the entire reach of fused-pipe, the Contractor shall
perform fusion work to connect two or three previously fused-pipe segments on the day of pipe-
bursting. The Contractor shall allow an additional 30-minute cool-down time for each fused-joint
before rough-handling or resuming pipe-burst operation. Internal beads at pipe joints can only be
left in place, with Inspector’s approval, when it is not feasible to fuse the entire reach of pipe prior
to pipe-bursting. Only one internal bead for every 200 feet of pipe is allowed.
If a manhole at one end of the pull is not intended to be replaced, the Contractor shall use the
appropriate equipment utilizing a hydraulic or pneumatic head to pull into a manhole without
disturbing the surrounding area of the manhole.
The pipe bursting tool shall make a tunnel along the path formerly occupied by the old sewer and
shall install the new pipe by pneumatic or static method, or a combination of both. The pipe-
bursting tool shall be of the type and size recommended by the tool manufacturer for the size of
pipe being burst and for the existing ground conditions. The Contractor shall use lubricating
fluids, such as bentonite or polymer slurry, injected behind the bursting head for pipe diameters
greater than 16”. Lubricating fluids can also be used if hard/dense soil condition is encountered.
The Contractor must clean the lubricant mud from the pipe at each lateral connection for proper
fusion saddle adhesion.
When the tool is pulled along the existing pipe, the pipe shall be broken up into small fragments
and these fragments driven into the surrounding pipe zone. The tool shall then install the new
pipe by pulling it into place.
The new sewer main shall be installed without any horizontal or vertical offsets. The invert of the
new sewer pipe should match the invert of the existing sewer at the exit of the upstream manhole
and at the entrance into the downstream manhole, regardless of the size and alignment of the
existing pipe.
The Contractor shall allow the new HDPE pipe to return to its original length and shape in the
unstressed state and then trim the excess pipe in the manholes. The HDPE pipe manufacturer's
recommendations shall be followed regarding the relief and normalization of stress and strain
due to temporary stretching or elongation after pulling operations are completed. Time allowed
for stress and strain relief shall not be less than 24 hours.
A minimum of three working days prior to pipe bursting mains or laterals, the Contractor shall
pothole, at minimum, all utility pipes crossing the pipe bursting alignment where the invert of the
existing sewer main being replaced is 6 feet deep or less. In addition, Contractor shall pothole
crossings with ACP water mains and primary electric lines/duct bank where the invert of the
existing sewer main being replaced is 8-1/2 feet deep or less.
Potholed utility pipes shall be fully exposed during pipe bursting for the Inspector to observe
while the new sewer main is passing under the potholed pipes. The pothole excavation shall be
extended to 1 foot below the bottom of crossing pipes and 2 feet below the bottom of crossing
ACP water mains or primary electric lines/duct bank. The contractor is responsible for all costs
resulting from damage to utilities during pipe bursting operations.
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SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 8
The upsizing method shall not cause excessive disruption to the above ground terrain or
improvements except for at the launching and receiving pits.
5. Service Connections: After the pipe has been pulled into place, the Contractor shall allow the
pipe to relax before cutting the ends of the new main or the lateral connection holes. The rest
period for the pipe shall be at least 24 hours and shall comply with pipe manufacturer’s
recommendation. The Contractor shall reconnect or replace all active sewer laterals along the
new main within 2 business days after the new pipe has been relaxed.
Electrofusion saddles shall be installed per Utility Standard Details for service connections.
B. Open Trench
1. Trench Excavation: The trenches shall be excavated to allow adequate width for access of
workers, sheeting and shoring installation, and to provide clearance necessary to avoid damage
to the main during installation. Care shall be taken to protect existing utilities. Refer to Utility
Standards Section 2200 3.4 for additional requirements.
2. Installation of the new main: Complete length of pipe from manhole to manhole, free of any
couplings (mechanical or electro-fusion), with exception to service connections at the main.
3. Service Connections: The Contractor shall reconnect or replace all active sewer laterals within
2 business days after the new main is installed. New sewer pipe shall be installed without any
horizontal or vertical offsets. Unless otherwise noted, the invert of the new sewer pipe should
match the invert of the existing sewer at the exit of the upstream manhole and at the entrance
into the downstream manhole, regardless of the size and alignment of the existing pipe.
Electrofusion saddles shall be installed per Utility Standards Details for service connections.
1.05 TESTING
A. Air pressure setup shall be in accordance with ASTM F1417, Constant Pressure Method. The
pipe shall be tested with low pressure air at 3.5 psi for 5 minutes with NO pressure loss. Wyes
shall be plugged during test. Tests shall be made in the presence of the Contractor and the City
Inspector or Engineer.
B. If the pipe fails the air test, the Contractor shall locate the source(s) of the leak and repair the
defect(s). The pipe shall then be retested.
C. TV Inspection: After passing the air test, both laterals and mains shall be CCTV per Section
2739, Cleaning and Video Inspection of Sewer Pipe.
D. Any pipe defects identified before the end of the 1-year guarantee period shall be expeditiously
repaired by the Contractor at no expense to the City.
1.06 CLEANING AND VIDEO INSPECTION
A. Initial Cleaning and Video Inspection
Prior to replacing the sewer mains, the Contractor shall clean and video-inspect the existing
sewer mains. Based on the lateral connections to the main observed from the video inspection,
the Contractor shall accurately identify all active sewer laterals and verify each active lateral’s
149
SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 9
location and/or alignment. The cost to identify active sewer laterals shall be included in one or
more bid items.
B. Final Cleaning and Video Inspection
After installation, pipe and structures shall be cleaned and video inspected in accordance with
Project Specifications and the current Water Gas and Wastewater Utility Standards. The
Contractor shall repair all defects at no additional cost to the City.
END OF SECTION
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15
6
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 1
SECTION 2736
CURED-IN-PLACE PIPE (CIPP)
1.01 GENERAL
A. Scope
This section covers the installation of cured-in-place pipe (CIPP) rehabilitation of existing sewer
pipe. The cured pipe shall be as specified herein and installed at only the locations approved by
the engineer and shown on the Drawings.
B. General Bid Requirements:
1. The Contractor, or his/her CIPP Sub-contractor, shall clean and remove all debris, including
any degree of root infiltration, using the recommended cleaning method for pipe cleaning as
specified in Section 2739, to return host pipe back to CIPP manufacturer’s recommended
parent host pipe condition for installation of CIPP lining.
2. The Contractor, or his/her CIPP Sub-contractor, shall repair and/or prepare host pipe using
methods recommended by the CIPP manufacturer, not limited to chemical grouting or
sectional pipe spot repair.
3. The Contractor and his/her CIPP Sub-contractor, must factor in ambient conditions which
may affect properties related to the CIPP materials, such as site and weather conditions
during installation. Scheduling of CIPP material procurement, proper and feasible
accessibility of CIPP on-site mobilization and understanding of proper handling of uninstalled
CIPP material properties on site may affect the CIPP installation. Supplier scheduling,
material procurement, bypass setup & spill mitigation plan, and site assessment
responsibilities shall be factored into the proper CIPP installation process.
4. Refer to Water, Gas, and Wastewater Utility Standards Section 2730 for requirements of flow
bypass plan.
5. The curing and installation methods of the liner shall be described and included with the Bid.
The Contractor shall demonstrate that the method is applicable and that his/her experience
in using the method is proven.
6. The Contractor, or his/her CIPP Sub-contractor, shall be properly licensed and trained to a
cured-in-place pipelining process having of a combined total of 20,000 lineal feet of
successful installation in the United States within the last two (2) years, in pipelines ranging
from 8 to 48 inches. Documentation of the licensing and details of two (2) years minimum
training of the on-site superintendent and foreman of the Contractor, or his/her CIPP Sub-
contractor, performing the actual installation, shall be submitted, using the City-provided
forms #2736-1 and #2736-2 (use multiple sheets if necessary), with the Bid.
C. Process Description
Installation of the Cured-In-Place Pipe shall be accomplished by the use of an inversion process
or a winched-in application. The reconstruction of the existing line shall be accomplished by
installing a flexible liner which is first impregnated with a thermosetting resin. The liner is either
inverted into the pipeline by using hydrostatic head (water pressure), compressed air pressure or
some other approved inversion method, or pulled into the pipeline from manhole to manhole
157
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 2
using mechanical equipment (winch). After full insertion, the liner is cured by circulating hot
water, ultra-violet light or, introducing controlled air or steam throughout the length of the liner to
cure it into a hard, impermeable pipe. This “pipe” shall extend the full length of the original sewer
from manhole to manhole, and shall provide a structurally sounds, jointless, tight-fitting,
watertight pipe within a pipe.
D. References
The following documents form a part of these specifications to the extent stated herein and shall
be the latest edition thereof.
American Society for Testing and Materials (ASTM):
ASTM D 256 Standard Test Methods for Impact Resistance of Plastics and Electrical
Insulating Materials
ASTM D 543 Resistance of Plastics to Chemical Reagents
ASTM D 638 Tensile Properties of Plastics
ASTM D 732 Standard Test Method for Shear Strength of Plastics by Punch Tool
ASTM D 790 Flexural Properties of Unreinforced and Reinforced Plastics and Electrical
Insulating Materials
ASTM D 2990 Tensile, Compressive, and Flexural Creep and Creep-Rupture of Plastics
ASTM D 3567 Standard Practice for Determining Dimensions of “Fiberglass” (Glass-Fiber-
Reinforced Thermosetting Resin) Pipe and Fittings
ASTM D 5813 Cured-in-Place Thermosetting Resin Sewer Pipe
ASTM F 1216 Standard Practice for Rehabilitation of Existing Pipelines and Conduits by
the Inversion and Curing of Resin-Impregnated Tube (1991 Revision)
ASTM F 1743 Standard Practice for Rehabilitation of Existing Pipelines and Conduits by
Pulled-in-Place Installation of Cured-in-Place Thermosetting Resin Pipe
ASTM F 2019 Standard Practice for Rehabilitation of Existing Pipelines and Conduits by
Pulled-in-Place Installation of Glass reinforced Plastic (GRP) Cured-in-
Place Thermosetting Resin Pipe (CIPP)
ASTM F 2561 Standard Practice for Rehabilitation of a Sewer Service Lateral and Its
Connection to the Main Using a One Piece main and Lateral Cured-in-Place
Liner
National Association of Sewer Service Companies (NASSCO): Recommended Specifications for
Sewer Collection System Rehabilitation.
1.02 SUBMITTALS
The Contractor shall submit for approval by the Engineer the following information:
158
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 3
A. Engineering calculations for the design of the liner thickness. The design calculations shall be
checked and approved by a Registered Professional Civil or Mechanical Engineer in the State of
California. Liner design calculations shall be supported by field analysis, technical assumptions,
and section 1.03C, Liner Design Criteria, of this specification. Final approval of the design
calculations shall be given by the Engineer.
B. Certification from the installer that all lining materials and resins furnished under this specification
were manufactured, samples, tested and inspected in accordance with ASTM F 1216, latest
edition, “Standard Practice for Rehabilitation of Existing Pipelines and Conduits by the Inversion
and Curing of Resin-Impregnated Tube.”
C. Manufacturer's recommendations for the installation of the CIPP including resin application,
curing process details (including temperature control), storage procedures, service connection
methods, trimming and finishing, and quality control measures to be used for cured-in-place pipe
lining of main-lines and services.
D. Certification from the manufacturer(s) that the installer is licensed to perform the work.
E. Certification from the manufacturer(s) that the resin material complies with the required
application, meets the intended service condition, and that the resin will meet the physical
requirements set forth in this specification. Information from the resin manufacturer shall include
specifications, characteristics and properties of the resin, methods of application, curing
temperatures, and duration of temperature (step cooking temperatures/hours at each and final
stages).
F. Flow bypass plan.
G. Independent test laboratory results of field samples taken at locations specified by the Engineer.
Prior to construction, the Contractor shall provide the contact information for the third party
independent testing laboratory for approval.
H. The beginning and end of the pipe lining shall be cut flush at the inlet and outlet points in the
manhole. The ends shall be sealed to the rehabilitated pipeline. The sealing material shall be
compatible with the pipe liner and shall provide a watertight seal.
I. Air test service connection for water tightness after the main has been installed. Contractor shall
provide test process submittals for all sewer lateral connections for reinstatement, based on
CIPP manufacturer’s recommendations for all active sewer lateral connections (SLC) as
specified in Section 1.05.
1.03 MATERIALS
All materials and procedures used in the cured-in-place pipe rehabilitation process shall be equal to
or exceed the manufacturer's standards.
A. Liner: The liner tube shall be fabricated to meet performance requirements as specified in
section 1.03D, Finished and Cured Liner Properties, of this specification.
Fiber Felt Tube System: The felt tube shall be a thermoplastic polyester or acrylic tube
consisting of one or more layers of flexible needled felt or an equivalent woven and/or non-woven
material capable of carrying resin, and with sufficient needling and cross-lapping and strength to
159
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 4
withstand the installation pressures and curing temperatures. The felt tube to be furnished shall
be compatible with the resin and catalyst systems to be utilized. The tube shall be free of tears,
holes, cuts, foreign materials and other defects and will be subject to inspection by the City.
The finished lining shall consist of an inner plastic coating and outer polyester felt layer (or
layers) impregnated with a thermosetting resin and fabricated to fit tight against the existing pipe
wall. An allowance shall be made for circumferential stretching during inversion.
Contractor shall determine the minimum tube length necessary to effectively span the designated
run between manholes, unless otherwise specified. Contractor shall field verify the lengths in the
field prior to impregnation of the tube with resin, to ensure that the tube will have sufficient length
to extend the entire length of run.
B. Resin/Catalyst
The resin used shall be compatible with the rehabilitation process used and designed for a
wastewater environment. The resin shall be able to cure in the presence or absence of water,
and the initiation temperature for cure shall be as recommended by the resin manufacturer and
approved by the Engineer. The resin shall have sufficient thixotropic properties to obtain non-
draining characteristics when impregnated into the fiber fabric.
Unless otherwise specified or approved by the Engineer, the resin shall be a polyester system for
typical residential sewage and shall be able to meet the service conditions specified for the tube
system. For commercial, industrial, or other areas with a potential for sewage that affects
polyester, epoxy or vinyl ester resin shall be required as determined by the City.
The Engineer shall also be informed in advance, for verification and inspection of the resin
material at the "wet out" of the tube. The inspection shall be at the discretion of the Engineer,
which shall not relieve the Contractor of his responsibilities. The wet-out procedure shall utilize
the resin and catalyst in sufficient quantities to ensure complete impregnation of the liner and
provide the properties specified in Section 1.03D, Finished and Cured Liner Properties. The
installer shall provide qualified field personnel to ensure acceptable installation workmanship.
The catalyst system shall be compatible with the resin and other materials to be utilized in the
rehabilitation process. Quantity and type of catalyst shall be selected based on the curing
conditions and recommendations of the resin manufacturer.
C. Liner Design Criteria
The Cured-In-Place Pipe thickness shall be calculated and designed upon the following physical
conditions of the existing host pipe and per ASTM F1216, Appendix X.1:
1. All pipes shall be considered fully deteriorated.
2. All pipes shall be subjected to a soil load of 120 lbs./cu. ft., with applicable live load, and
water table two (2) feet below the top of the ground.
3. Pipes in good condition shall have a minimum of two percent (2%) ovality in the
circumference. A higher value of ovality shall be used if the pipe is deteriorated.
4. Factor of safety (N) of 2.0 shall be used for calculations.
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CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 5
Conditions 1 and/or 2 above may change after the initial CCTV report, if approved by the
Engineer. The Engineer shall have the right to modify/change the required liner thickness,
depending upon field conditions evident from the video footage and/or tested product values.
D. Finished and Cured Liner Properties
The finished cured-in-place pipe liner shall be white or light gray, fit tightly and neatly against the
existing pipe walls. The liner shall be fabricated from materials which, when cured, will be
suitable for continuous service in sewerage environments containing hydrogen sulfide, carbon
monoxide, carbon dioxide, methane, dilute (10%) sulfuric acid at an average wastewater
temperature of 80qF, dilute (10%) phosphoric acid, petroleum hydrocarbons, gasoline, vegetable
oil, tap water (pH 6.5 - 9), up to one (1) hour per day exposure to five percent (5%) sodium
hydroxide up to a pH of 11, moisture saturation, and external exposure to soil bacteria and
chemical attack which may be due to materials in the surrounding ground or sewage within. 0%
shrinkage allowed.
The cured-in-place pipe system shall conform to and comply with the requirements above, and
meet or exceed the minimum standard physical properties as follows:
STRUCTURAL/MECHANICAL
PROPERTY
ASTM
TEST
METHOD
ASTM
MINIMUM SHORT
TERM VALUE
ASTM
MINIMUM LONG
TERM VALUE
TENSILE STRENGTH (@ Yield) D-638 4,000 psi.
TENSILE MODULUS D-638 250,000 psi. 125,000 psi
FLEXURAL STRENGTH D-790 5,000 psi.
FLEXURAL MODULUS D-790 300,000 psi. 150,000 psi
SHEAR STRENGTH D-732 5,500 psi.
IMPACT STRENGTH D-256 1.9 in.-lb.
The initial stiffness factor shall conform to the following table:
1.Stiffness factor shall be determined in accordance with ASTM D2412.
2.Safety factor not included.
Nominal ID of
Original Pipe
(Inches)
Stiffness Factor (EI)1
(in3-lbf/in2)
Maximum Allowable Depth of
Groundwater Above Invert.2
(Feet)
6 328 238
8 328 96
10 328 48
12 328 27
12 1109 96
15 1109 48
18 1109 27
161
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 6
1.04 CURED-IN-PLACE PIPE (CIPP) LINER – MAIN INSTALLATION
The Contractor's operations to furnish and install the liner shall be in strict conformance with the
component materials and manufacturer's recommendations. The procurement of the CIPP liner,
ambient temperatures, weather, site accessibility and conditions, sewage bypass setup, and
mobilization to the project location are to be considered when the Contractor or subcontractor
schedules their sequence of work and the quality of the installation.
The host pipeline shall be cleaned and televised prior to CIPP installation. There will be debris
and/or root balls encountered that require the use of the appropriate cleaning method for their
removal to bring the host pipe to be within the parameters recommended for CIPP installation.
Where structural defects are present, the Contractor shall perform chemical grouting or point
repairs to the host pipe to ensure a successful liner installation. All protruding laterals encountered
during the pre-installation inspection shall be trimmed to be flush with the pipe interior as
practicable.
The Contractor or their CIPP subcontractor shall consider ambient temperatures, weather, and site
conditions which may affect physical or chemical properties of the CIPP liner when scheduling
work. The outside diameter of the liner being inserted shall be properly sized to allow for expansion
so that the CIPP liner can fit tightly against the host pipe.
The liner shall be installed through the existing manholes, in accordance with the manufacturer's
recommendations and procedures. The finished pipe on mainline reaches shall be continuous over
the entire length between manholes. A sealing material compatible with the liner shall be installed
at the entrance to each manhole between the liner and the existing pipe to provide a watertight
seal.
The Contractor shall submit to the Engineer a detailed plan of construction including the installation
procedures, equipment set-up, and the locations of the proposed access points for approval. The
Contractor shall have an approved plan of construction prior to commencing any construction.
During the curing process, the Contractor shall keep logs, charts and/or graphs of the liner
temperatures at the upstream and downstream manholes to ensure that proper temperatures and
cure times have been achieved. These documents may be requested by the Engineer at any time
during and after the curing process.
Immediately after curing of the tube and after the City’s acceptance of the hydrostatic exfiltration
testing, The Contractor shall proceed with the reestablishment of active wastewater connections to
the main in conformance with Section 2736, 1.05 “Reinstatement of Sewer Laterals”.
1.05 REINSTATEMENT OF SEWER LATERALS
Following the approval of the hydrostatic exfiltration test on the liner, the Contractor shall reinstate all
active sewer lateral connections (SLC) within 24-hours. Appropriate temporary flow control shall be
setup if needed, before the laterals are reinstated, to convey sewage and prevent sewer
backup/overflow.
The SLC is the interface between the sewer lateral and the sewer main. All SLC’s shall be exposed
without excavation using a City-approved remote-controlled cutting device. A backup remote-
controlled cutting device shall be kept on-site in case of malfunction. Where a SLC cannot be
reestablished using a remove-controlled cutting device, the Contractor shall notify the Engineer and
request approval to open-cut and reinstate the SLC.
162
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 7
When the SLC is exposed, the invert of the sewer lateral shall match the bottom of the reinstated
lateral opening. After exposing all active SLC’s, the Contractor shall perform CCTV inspection of the
main and laterals to locate damage or leaks. Laterals shall be inspected at a minimum of 16-inches
beyond the SLC.
Any infiltration found during CCTV-inspection shall be addressed by a SLC sealing system
requested by the Engineer. Any roots, protrusions, or debris found that will interfere with the SLC
sealing method shall be removed by the Contractor. If the inspection reveals an obstruction cannot
be removed by conventional sewer cleaning equipment, the Contractor shall be required to make a
point repair to excavate and remove the obstruction. The Contractor shall notify the Engineer prior
to the commencement of work.
When required, the Contractor shall divert sewage around section or sections of mainline pipe
where the SLC sealing is located. The wastewater lateral requiring a SLC sealing system shall be
inactive during the time of installation.
The SLC sealing method employed by the Contractor shall be one of the following methods and be
compatible with the main CIPP lining system.
A. Chemical Grout:
The lateral connection shall be sealed if the lateral connection does not pass the air test or
infiltration is visible. The Contractor shall use pressure inject chemical grout through a
lateral packer into the annual space between the lateral grouting plug and the lateral pipe.
Upon complete application of the chemical grout, the Contractor shall complete an air test.
If the SLC fails the air test, the Contractor shall repeat the grouting procedure at no
additional cost to the City.
Where grout blockage exists from grouting operations, the Contractor shall clear the lateral
at no additional cost to the owner.
B. Full-Wrap or “T-Style”:
The sealing material shall consist of a cured-in-place resin saturated felt tube that provides
a full-wrap liner in the mainline centered at the SLC with the liner extending at least 4-
inches into the lateral.
Installation shall conform to Section 7 of ASTM 2561. The installation method shall provide
an air-tight seal of the SLC sealing system to the mainline pipe and SLC. Prior to
installation, the felt tube shall be saturated with resin at the Work site and stored at the
temperature specified by the resin manufacturer. After installation, the felt liner shall be
cured as specified by the resin manufacturer. The SLC sealing tube for the lateral shall
extend a minimum of 4-inches from the mainline to the lateral.
After installation is complete and the SLC seal has cured, the Contractor shall perform
adhesion testing in conformance with Section 2736, Section 1.06 C. The Contractor shall
also perform an air pressure test on the cured SLC sealing system in accordance with
Section 2736, Section 1.06 D and submit all passing test results
C. “Brim Style”:
163
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 8
The sealing material shall consist of cured-in-place resin saturated fiberglass or felt
material that provides a brim section in the mainline with the brim centered around the SLC
with a liner section extending into the lateral. The length of the liner extending into the
lateral shall be a minimum of 4-inches from the mainline.
The fiberglass or felt material and liner shall be saturated with resin at the Work site and
stored at the temperature specified by the resin manufacturer. The resin saturated SLC
sealing system shall be loaded on an applicator apparatus, attached to a robotic device
and positioned in the mainline at the SLC to be sealed.
The robotic device shall be equipped with a CCTV camera which shall be used to align and
center the SLC sealing system within the lateral opening. The applicator apparatus shall
include a bladder or an approved mechanical device of sufficient length in the mainline and
lateral such that the inflated bladder or approved mechanical device extends beyond the
end of the SLC seal.
The insertion pressure shall be adjusted to fully deploy the SLC sealing system in the
lateral and hold the ends of the SLC seal ends against the pipe walls. The SLC sealing
system shall produce a smooth transition between the SLC seal and the pipe walls without
a ridge or gap between the SLC seal and the inner diameter of the mainline and the lateral.
Insertion pressure shall be maintained for the duration of the curing process. Curing shall
be as specified by the resin manufacturer.
After installation is complete and the SLC seal has cured, the Contractor shall perform
adhesion testing in conformance with Section 2736, Section 1.06 C. The Contractor shall
also perform an air pressure test on the cured SLC sealing system in accordance with
Section 2736, Section 1.06 D and submit all passing test results.
1.06 TESTING
A. Hydrostatic Exfiltration Test: The Contractor shall perform a hydrostatic exfiltration test on the
main after the inversion and curing of the liner but before the reinstatement of the laterals. This
test shall be performed to determine if the liner installation is watertight. This test shall be
performed in conformance with ASTM F1216. The test shall be conducted for a minimum of one
(1) hour.
B. Pipe Samples Testing: The Contractor shall prepare a minimum of one (1) CIPP sample for
testing for inversion in accordance with ASTM F1216 and ASTM F1743. Sample(s) shall conform
to the following two methods:
1. For host pipe diameters 18” and smaller, the sample should be cut from a section of cured
CIPP at an intermediate manhole or at the termination point that has been inverted through a
like diameter pipe which has been held in place by a suitable heat sink, such as sandbags.
2. For host pipes larger than 18” in diameter, the sample should be fabricated from material
taken from the liner and the resin/catalyst system used and cured in a clamped mold placed
in the down tube.
The samples for each of these cases should be large enough to provide a minimum of three
specimens. The samples shall be tested by a certified independent third-party testing laboratory
164
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 9
by the Contractor. The lab shall provide the Engineer for approval with certified test results. The
following test procedure shall be performed after the sample is cured and removed:
1. Short-Term Flexural (Bending) Properties – The initial tangent flexural modulus of elasticity
and flexural stress shall be measured for gravity and pressure pipe applications in
accordance with ASTM D790 and should meet the short-term flexural modulus and flexural
strength values used in the thickness designs of the CIPP previously submitted.
2. Wall thickness at any point shall not be less than 87.5% of the design thickness.
C. Lateral Chemical Grout Sealing Air Pressure Test: The joint testing pressure shall be equal to
0.5 psi per vertical foot to top of pipe depth plus 2 psi. Test pressures shall not exceed 10 psi
without approval of the Engineer. If pressure drop is found to be greater than 2 psi within 15
seconds, the application of grout shall be considered unsuccessful and the Contractor shall
repeat the grouting procedure and air testing procedure at no additional cost to the City.
D. SLC Sealing System Adhesion Testing: The adhesion testing shall be conducted after the
SLC seal has cured in accordance with the manufacturer’s specifications, but before the final
video inspection is performed. Adhesion testing shall consist of inserting a high velocity,
hydraulic cleaning type, 360-degree spinning nozzle and CCTV camera in the mainline pipe and
position the nozzle at the SLC seal. The water from the nozzle shall be directed downstream for
a minimum of 1 minute, at each edge of the SLC seal in the mainline at the minimum pressure of
1,500 pounds per square inch and a minimum flow rate of 65 gallons per minute.
E. SLC Sealing System Air Pressure Test: The cured SLC sealing systems shall be air pressure
tested. Test plugs shall be placed upstream and downstream of the SLC sealing system in the
mainline and, upstream of the SLC sealing system in the lateral. The test pressure shall be 4
pounds per square inch of a 3-minute test time during which the pressure shall not drop below
3.5 pounds per square inch. If the SLC sealing system fails this test, the test plug at the
upstream end of the lateral may be moved onto the SLC opening and the test conducted again. If
the second test passes, the SLC sealing system will be deemed to have passed the test.
1.07 CLEANING AND VIDEO INSPECTION
A. Initial Cleaning and Video Inspection
The existing sewer shall be cleaned and video inspected in accordance with Section 2739 of
these Specifications. The Contractor shall verify location of active lateral connections at this time.
B. Final Cleaning and Video Inspection
After CIPP lining is complete and the services have been reinstated, the pipe liner and SLC
sealing systems shall be cleaned and video inspected in accordance with Section 2739 of these
Specifications. The Contractor shall repair all defects at no additional cost to the City.
1.08 WARRANTY AND QUALITY ASSURANCE
A. The Contractor shall provide to the City a warranty to be in force and effect for a period of two (2)
years from the date of acceptance by the City. The warranty shall cause the Contractor to repair
or remove and replace the liner should failure result from faulty materials or installation.
165
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 10
B. Correction of failed liner or liner deemed unacceptable, as a result of the post video inspection
and/or test reports for structural values, thickness, chemical resistance, etc., shall always be the
responsibility of the Contractor, at no extra cost to the City. Method of correction/repair shall be
approved by the City with prior field demonstration, if required. It shall be understood that
minimum criteria of the specification shall not be lowered to compromise with lower than the
required test values, unless approved in writing.
C. The finished liner shall be continuous over the entire length of run between two manholes and
shall be free from visual defects such as foreign inclusions, dry spots, pinholes, and
delamination. The finished liner shall meet or exceed the requirements of Section 1.03D,
Finished and Cured Liner Properties.
D. Wrinkles in the finished liner pipe which exceed five percent (5%) of the pipe diameter are
unacceptable. Where this is visible in CCTV inspection footage, the Contractor shall mill down
the wrinkled segment below the spring line to be flush with the internal diameter of the newly
installed liner. Additionally, any wrinkles that traverse the invert and impede flow shall be
removed. Repair of the removed sections shall be proposed by the Contractor and approved by
the Engineer.
E. The Contractor shall carry out the operations in strict accordance with all applicable OSHA
regulations. Particular attention is called to those safety requirements involving work on an
elevated platform and entry into a confined space.
F. Where SLC sealing systems are installed and fail either the adhesion or the second air pressure
test, the Contractor shall be required to remove and replace or repair the SCL sealing system
G. The Contractor shall be required to perform post-construction CCTV inspection where chemical
grout is applied.
END OF SECTION
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SANITARY SEWER LATERAL SECTION 2737
CITY OF PALO ALTO SECTION 2737 PAGE 1
SECTION 2737
SANITARY SEWER LATERAL
1.01 SCOPE
This section covers installation of sewer laterals. Laterals shall be installed as specified herein and at
the locations shown on the Drawings.
1.02 SUBMITTALS
The Contractor shall submit for approval by the Engineer the following information:
A. Manufacturer's literature on the materials identified below. Literature shall include recommended
installation procedures.
B. Certification by the manufacturer that all pipe and fittings furnished under this specification were
manufactured, sampled, tested, and inspected in accordance with the standards specified herein.
The date the pipe and/or fittings were manufactured shall also be included in the Certification.
1.03 MATERIALS
Sanitary sewer lateral materials shall meet the requirements of this section, Section 2735 (Polyethylene
Sewer Pipe), and Section 2300 (Polyethylene Pipe Installation for Water, Gas and Wastewater).
1. HDPE Pipe: HDPE, SDR 17, 445574C D, or E as described in ASTM D3350. The HDPE pipe
shall have a white or light gray interior by Performance Pipe “DriscoPlex 4100” or approved
equal.
2. Flexible Anti-Radial Shear “ARC” Couplings: Neoprene flexible, shielded, anti-radial shear
coupling per ASTM C1173 with 300 series stainless steel clamp band, housing, screws, shield
and eyelet. Fernco Inc. "RC SERIES", or approved equal.
a. Note: All connections shall be made with butt fusion or electrofusion as specified in Section
2735 (Polyethylene Sewer Pipe) and Section 1.04 of this specification. Couplings will only be
allowed with prior approval of the Engineer for special circumstances.
3. Flexible Tap Saddles with Pressure Kit: Specially formulated high durometer PVC flexible
saddle with stainless steel clamps per ASTM D5926 by Fernco , Inc., or T-Flex Sewer Saddle by
Mission Rubber Co.
a. Note: Pressure Kit by Fernco, Inc. contains bentonite tape water seal, plastic-coated steel
reinforcing bars and stainless steel clamps. This kit creates a water tight seal on all four
sides of tap saddle.
4. T Cone Plugs: Expandable pipe plug with no metal parts by ETCO Specialty Products, Inc., or
approved equal.
5. Cleanout Box: Christy F08 curb valve box with F08C cast iron lid or G05T (Traffic Rated for
driveways and approaches) with G05CT cast iron lid or approved equal.
6. Elastomeric Sealant: High performance, one-part, polyurethane sealant. Vulkem 921 by
Tremco, or approved equal.
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SANITARY SEWER LATERAL SECTION 2737
CITY OF PALO ALTO SECTION 2737 PAGE 2
Any pipe, fittings, or appurtenances that do not conform to the above specifications shall be rejected
and shall be removed immediately from the work site by the Contractor.
1.04 JOINING AND INSTALLATION
A. The Contractor is responsible for verifying an existing lateral’s horizontal and vertical alignment.
B. All new laterals shall be installed perpendicular to the main, at uniform slope, and without any
changes in lateral horizontal alignment or grade, unless otherwise approved by the Engineer.
Pipe bedding shall provide uniform and continuous support of the pipe barrel.
C. Lateral replacement by pipe bursting is allowed if the existing lateral meets the horizontal and
vertical alignment standards and the City-owned portion of the lateral is free of cross-bores. If
the existing lateral connection point at the main is more than five feet offset from the cleanout, as
measured on the field along the main, the Contractor shall abandon the existing lateral and install
a new lateral. The new lateral will be permitted to be installed at an angle to the main to avoid
utility conflicts or to establish a higher cleaning velocity. Pipe bursting requirements are specified
in Section 2735 Polyethylene Sewer Pipe.
D. All ACP laterals shall be replaced by open cut.
E. Pipe and fittings shall be handled, joined, and installed in accordance with the instructions and
recommendations of the pipe manufacturer.
F. If lubricant mud was used to replace the sewer main by pipe-bursting, extra precaution shall be
used to thoroughly clean the sewer main from lubricant mud at each service connection for
proper fusion saddle adhesion.
1.05 LATERAL CONNECTIONS
A. Lateral Connections to Mains
MAIN MATERIAL CONNECTION METHOD STANDARD DETAIL
HDPE ELECTROFUSION SADDLE WWD-05 DETAIL C
VCP CUT IN NEW VCP WYE WWD-05 DETAIL A
SDR26 PVC CUT IN NEW PVC WYE WWD-05 DETAIL A
C900 PVC STRAPPED RUBBER SADDLE WWD-05 DETAIL B
PCC / RCP TAP-TITE OR INSERTA-TEE WWD-06
1. Upon Engineer’s approval, “Tap-tite” or “Inserta Tee” can be used on existing C900 and
C905 PVC, SDR26 PVC, and VCP mains 10-inch and larger.
2. Existing PVC and ABS laterals in a condition acceptable to the City shall be reconnected to
new HDPE main using Electrofusion Saddle and Flexible Coupling. The assessment of the
lateral condition will be performed by CPA Wastewater Operations.
3. Special fittings for connection to sewer liner will be reviewed on a case by case basis.
B. Lateral Connections to Manholes
1. The preferred method of sewer lateral connection to existing manhole wall or base is core
drilling. Hammering of holes is acceptable but limited to a maximum size of sixty-pound
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SANITARY SEWER LATERAL SECTION 2737
CITY OF PALO ALTO SECTION 2737 PAGE 3
jackhammers. The use of precision “chipping” equipment will only be acceptable with prior
approval from the on-site field Inspector.
2. Lateral crowns (top inside surface of the pipe) shall not be lower than the elevation of the
outlet main crown in the manhole, unless otherwise approved by the Engineer.
An appropriate manhole water stop gasket shall be used on all plastic pipe entering
manholes. For PVC and HDPE pipe, water stop gasket shall be Newby Rubber, Inc., Mission
Rubber, or approved equal.
3. Channel bottoms shall be worked to provide a smooth flowing transition from the new laterals
to the outlet channel. See Section 2738 (Precast Concrete Manholes) for outside drop piping
requirement.
4. Pipe penetrations shall be sealed with a non-shrink grout.
A. Cleanouts
1. A sanitary sewer cleanout shall be provided in the planting strip or in the case where the
sidewalk and curb are integral, at the back of sidewalk.
2. A T Cone Plug shall be used to plug the cleanout. T-Cone Plugs shall not be over tightened.
Plugs shall be tightened just enough to hold the plug in place and prevent inflow into the
pipe.
B. Inspection: All lateral connections shall be inspected and approved by the Utilities Inspector.
Applicants or developers shall schedule the inspection of new lateral connections at least one
week in advance.
1.06 SEWER LATERAL ABANDONMENT PROCEDURE
A. Excavate and disconnect the existing lateral at the main.
1. Plug the existing wye or tee with cement sock or T-cone plug. Damaged or broken wye/tee
connections and all tapped/saddle connections shall be removed and replaced with a new
section of pipe in kind.
2. For lined mains (CIPP, deformed and reformed, sliplining), remove the abandoned lateral at
the joint of the factory wye or tee, or at the closest joint of the lateral to the main. Install
cement sock or T-cone plug at wye or tee and at the downstream end of the abandoned
lateral. Fill the abandoned lateral with at least 2 feet of CDF at both ends of the abandoned
lateral.
B. The cleanout and riser shall be cut and plugged at least 3-feet below the finished grade. In non-
paved areas, the voids shall be filled with suitable material compacted to a relative compaction of
90% and concrete plugged. For paved areas, the remaining voids shall be filled with CDF, or
other flowable compaction fill and be concrete plugged, and the pavement shall be restored.
Where the cleanout is located in sidewalk, curb, or gutter, the surface shall be restored to match
existing.
C. Backfill and restore surface paving or landscape per current Water, Gas & Wastewater and
Public Works Standards.
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PART III – SANITARY SEWER LATERAL SECTION 2737
CITY OF PALO ALTO SECTION 2737 PAGE 4
D. Abandonment of sewer laterals shall be scheduled and witnessed by CPA Utilities Inspector.
1.07 TESTING
A. The pipe shall be tested with low pressure air in accordance with ASTM F1417, Constant
Pressure Method. The pipe shall be tested with low pressure air at 3.5 psi for 5 minutes with NO
pressure loss. Wyes shall be plugged during test. Tests shall be made in the presence of the
Inspector.
B. If the pipe fails the air test, the Contractor shall locate the source(s) of the leak and repair the
defect(s) or relay the pipe, as necessary. The pipe shall then be retested until a satisfactory result
is obtained, at no expense to the City.
C. New laterals and/or reconnected laterals shall be video inspected per Section 2739 Cleaning and
Video Inspection of Sewer Pipe.
D. Despite any previous testing or CCTV inspection, any pipe defects developed before the end of
the 1-year guarantee period shall be expeditiously repaired by the Contractor at no expense to
the City.
END OF SECTION
172
CONCRETE MANHOLES SECTION 2738
CITY OF PALO ALTO SECTION 2738 Page 1
SECTION 2738
CONCRETE MANHOLES
1.01 SCOPE
This section covers the installation of new concrete sanitary sewer manholes and rehabilitation of
existing manholes. Manholes shall be as specified herein and installed at the locations shown on the
Drawings.
1.02 SUBMITTALS
The Contractor shall submit for approval by the Engineer the following:
A. Manufacturer's literature on the materials identified below. Literature shall include recommended
installation procedures.
B. Certification by the manufacturer that all precast sections furnished under this specification were
manufactured, sampled, tested, and inspected in accordance with the latest ASTM C 478 or
ASTM C 361.
C. Mix design of the concrete used for the pour-in-place manhole base.
1.03 MATERIALS
The concrete manhole materials are as follows:
A. Precast Sections: ASTM C 478. Forterra, Old Castle Precast, or approved equal. For greater
than 72-inch ID: ASTM C 361, Class D-25. Flush Bell design, centrifugally spun or wet cast.
Ameron, Concrete Pipe & Products, or approved equal.
B. Precast Manhole Base (upon Engineer’s approval only): ASTM C 478. Forterra, OldCastle
Precast, or approved equal.
C. Sealant: Ram-Nek, K.T. Snyder Company, Inc., or approved equal. Approved equal shall
meet or exceed all requirements of ASTM C990 Standard Specification for joints, concrete pipe,
manholes and precast box sections, using Preformed Flexible Joint Sealants. Meets
requirements of Federal Specifications SS-S210-A, "Sealing Compound Preformed Plastic For
Pipe Joints", Type 1, Rope Form
D. Frame and Cover: Rexus II 24” manhole frame and cover with spring bar lock as manufactured
by Pam Saint-Gobain or approved equal. When manhole lid is located within a traffic lane, the
hinge shall be located on the downstream side of the flow of traffic. See standard detail WWD-10
for casting imprint and additional details.
E. Concrete: CalTrans Standard Specification Section 90 Concrete.
F. Mortar: Section 51-1.02F, CalTrans Standard Specification. Mortar shall be non-shrink as
manufactured by Sika or approved equal.
G. Water Stops: Molded plastic or rubber water stops by Mission Rubber, Newby Rubber, or
approved equal.
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CONCRETE MANHOLES SECTION 2738
CITY OF PALO ALTO SECTION 2738 Page 2
H. Drop Manholes: Drop manholes shall be installed whenever a pipe centerline entering a
manhole has an invert elevation 30 inches or more above the invert elevation of the outlet pipe in
the manhole base. See standard detail WWD-09.
1.04 MANHOLE INSTALLATION
Manhole bases shall be poured in a dry trench, using Class 2 concrete. Concrete will be sampled at
the Engineer’s discretion. Upon Engineer’s approval, precast manhole bases may be used on straight
runs and terminal manholes only. No field modifications of precast manhole bases shall be allowed.
During the pouring of the manhole base, precautions shall be taken to ensure that the sewer pipes
entering and leaving the manhole do not move from the installed alignment and grade. Plugs shall
be placed in open pipes to prevent concrete from entering the lines. Water stops shall be used on all
plastic pipes entering the manhole to prevent groundwater from leaking through the manhole wall.
Water stop shall be molded plastic or molded rubber.
The channels shall be shaped in flowing curves as indicated on the drawings to ensure good
hydraulic characteristics for the flow of wastewater. A smooth, clean, hand rubbed finish shall be
given to the surfaces of the manhole base and to any joint mortar work. Transitions between different
sizes of pipes shall be smooth and regular. Cracks, joints, holes, etc., shall be sealed with Sika or
approved equal non-shrink grout or sealing compounds to ensure watertight manholes.
When an existing VCP sewer main pipe is entering or leaving a newly constructed manhole,
Contractor shall replace in kind, a small section of new VCP pipe and connect to the existing VCP
pipe with a Anti-Radial (ARC) flexible coupling. Contractor shall remove the bell by making straight
cuts on both sides of new VCP pipe, refer to standard detail WWD-07B & 08B for specifications on
pipe length.
No more than twelve (12) vertical inches of grade rings shall be used to adjust the level of the
manhole frame (12 inches maximum between the top of the tapered manhole section and the bottom
of the manhole frame). Manholes shall be plumb.
Backfill shall be placed uniformly around the outside of the manhole so as to not create differential
forces and the possibility of dislodging the manhole sections.
1.05 NEW MANHOLE TESTING
The Contractor shall conduct a vacuum test (prior to manhole backfill) or an exfiltration test (after
manhole backfill) on each manhole constructed. No testing is required on shallow manholes that are
24” or less in depth. The test shall be conducted by the Contractor in the presence of the City
Inspector or Engineer.
Vacuum tests shall consist of drawing a vacuum on a sealed manhole and measuring the time for the
vacuum to drop to a predetermined level. Vacuum tests shall be conducted in accordance with ASTM
1244-11 “Standard Test Method for Concrete Sewer Manholes by the Negative Air Pressure
(Vacuum) Test Prior to Backfill” as follows.
1. Contractor shall furnish all materials and equipment used for vacuum test.
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CONCRETE MANHOLES SECTION 2738
CITY OF PALO ALTO SECTION 2738 Page 3
2. Contractor shall furnish a vacuum test gauge that has a range of 0 to 30” Hg that can be
accurately read to 0.5 inch Hg and is in good working order; and a reliable source of vacuum
as needed to conduct the test.
3. Plug all manhole penetrations including lifting holes. Each plug must be installed at a location
beyond the manhole/pipe gasket (i.e., outside the manhole wall), and shall be braced to
prevent the plug or pipe from being drawn into the manhole.
4. Install the test head (e.g., a rubber ring “donut” type plug) inside the rim of the cast iron frame
at the top of the manhole and inflate it in accordance with the manufacturer's
recommendations.
5. Apply a vacuum to the test assembly and lower the internal pressure to approximately 10-
inch Hg vacuum. Permit the vacuum to stabilize for 1 minute, disconnect the vacuum source
and begin timing the test.
6. The time shall be measured for the vacuum to drop from 10-inches Hg to 9-inches Hg. The
manhole must maintain vacuum such that no greater than 1 inch Hg of vacuum is lost during
the specified test period per the following table:
Manhole Depth
(Feet)
Test Period Based On Manhole Size (seconds)
48 inch
Diameter
60 inch
Diameter
72 inch
diameter
Up to 8 20 26 33
10 25 33 41
12 30 39 49
14 35 46 57
16 40 52 67
18 45 59 73
20 50 65 81
>20 74 98 121
7. The manhole is acceptable if the time for the vacuum reading to drop from 10-inches Hg to 9-
inches Hg is greater than the test period. Manholes that fail the test shall be patched as
required and retested at no additional cost to the City.
8. Remove all temporary plugs and braces after each test.
Exfiltration tests shall consist of plugging incoming and outgoing sewer lines and filling the manhole
with water up to the rim. After initial absorption (15 minutes), if the water loss exceeds one inch in
depth in five minutes, the manhole shall have failed the test. Each manhole which fails the test shall
be carefully inspected to determine the problem and then resealed and retested until the water loss is
less than one inch in five minutes.
1.06 EXISTING MANHOLE REHABILITATION
A. Existing Structures
Contractor shall find, uncover and recover (if required) missing structures as noted on the plans
or stated herein. Contractor shall utilize sonde’s, TV equipment, metal detectors, excavation
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CONCRETE MANHOLES SECTION 2738
CITY OF PALO ALTO SECTION 2738 Page 4
equipment, and other equipment needed to locate the sanitary sewer structure. Contractor shall
expose and document the location.
B. Seal Manhole
Sealing manhole structures consists of cleaning, filling voids, grouting joints, stopping leaks, and
coating the interior of the manhole with a sealer. The sealer shall penetrate the existing concrete
and form crystalline structures within the pores of the concrete that will seal the concrete.
1. Path holes and cracks using Perco Patch by Perco Industries or Patch ‘n Plug by Xypex.
2. Stopping leaks shall be done by chemical injection through interior wall of the manhole or
rapid-setting cement-based water-stop mortar to stop the infiltration. Chemical injection shall
be used per manufacturer’s recommendations for the existing site conditions.
3. The seal coating shall be an acrylic modified cementitious coating that is self-curing, suitable
for spray or brush application. The seal coating shall be Brush bond as manufactured by
Perco Industries or Xypex Concentrate as produced by Xypex.
C. Coat Manhole
Coat manholes with a monolithic ultra high-build epoxy lining to rebuild, eliminate infiltration,
provide corrosion protection, and repair voids. Procedures for surface preparation, cleaning,
application and testing are described herein. All application procedures shall follow the
manufacturer’s guidelines and meet the following minimum requirements:
1. Surface Preparation
a. Clean Surface – Clean the surface by removing any laitance, dust, unsound, looser, or
contaminated material, plaster, oil, paint, grease, corrosion deposits or bacteriological
growths. Chemical cleaning aids may be used with water blast equipment, however,
Engineer must approve detergents or degreasers proposed by the contractor and must
be suitable for the water temperature used in any pressure washer system employed.
Where breaking out mortar is not required, roughen the surface and remove any laitance
by mechanical means, low-pressure hot water blast (minimum 3500 psi pump pressure
at 4 gpm), or high-pressure cold water blast (>5000 psi pump pressure at 4 gpm) with or
without sand injection as is appropriate, abrasive (sand) blasting, acid etching and water
cleaning, or shotblasting to a sound profile surface. Follow surface cleaning procedures
with a soaking rinse of chlorinated water to destroy remaining biologics and neutralize
the surface. The chlorine solution shall be rinsed with fresh water after not less than
fifteen minutes dwell time. Test the wet surface pH with universal pH indicator paper with
a range of pH 0-10, or other suitable test instrument. Acceptable surface pH for epoxy
grouting repairs and lining shall be not less than 6 or more than 9.
b. Stop Leaks/Fill Voids – Seal leaks with epoxy grout on the surface that is coated. Fill any
voids with epoxy patching material or grout according to the manufacturer’s
recommendations for flowing or weeping water conditions, rapid setting cementitious
“plug” materials may be used instead of epoxy grouts. Exterior injection of a gel type
chemical grout shall be used, if necessary.
2. Apply Coating: After the surface is properly prepared to apply the coating, apply the epoxy
liner by trowel or spray. The epoxy liner thickness shall be a minimum of 125 mils over the
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CONCRETE MANHOLES SECTION 2738
CITY OF PALO ALTO SECTION 2738 Page 5
entire surface. Manholes shall be coated from the frame and cover to the pipe in the channel.
If the pipe does not go through the manhole, the coating shall extend to at least the
springline of the pipe. The applicator shall be certified by the coating manufacturer to apply
the coating.
The inspector shall verify that the surface preparation, coating application, and final product
meet the requirements specified herein and the manufacturer’s requirements. A
manufacturer’s representative shall also be available for consultation and site visits, if
required by the City.
3. Test Requirement for Coated Manhole: Testing of coated manholes shall follow epoxy
manufacturer’s recommended testing method and procedures.
D. Drill Holes
Drill a hole or enlarge existing hole to 1.25” in diameter through the manhole cover.
E. Modify Channel
Chip and/or rework channels within the manhole to improve the flow through the manhole and to
the new pipes and to allow better access for video equipment. Channels shall be chipped to
sound material and approximate contour. Chipped areas shall be smoothened out using a
cementitious patching material.
F. Frame and Cover
Replace existing frame and cover and reset with a concrete ring as described in the Standard
Details.
G. Realign Frame and Cover
Realign existing frame and cover and reset with a concrete ring as described in the Standard
Details.
H. Raise Manhole
Add one 48” barrel section up to 3 feet and/or 24” rings up to the 12 inches to raise the
manhole’s frame and cover to grade, if not noted on the plans or described herein. Reset frame
and cover with a concrete ring as described in the Standard Details.
1.07 CONNECTIONS TO EXISTING MANHOLES
The preferred method of sewer lateral connection to existing manhole wall or base is core drilling.
Hammering of holes is acceptable but limited to a maximum size of sixty-pound jackhammers. The
use of precision “chipping” equipment will only be acceptable with prior approval from the on-site field
Inspector.
A water stop shall be used on all plastic pipe entering manholes. All pipe penetrations shall be
sealed with a non-shrink grout. Channel bottoms shall be reworked to provide a smooth flowing
transition from the new pipes to the outlet pipe. Subject to manhole testing as described in Section
1.05.
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CONCRETE MANHOLES SECTION 2738
CITY OF PALO ALTO SECTION 2738 Page 6
1.08 EXISTING MANHOLE TESTING
The Contractor shall conduct a vacuum test on each rehabilitated manhole and/or each manhole in
which a new main is connected as part of a capital improvement project. Each test shall be
conducted as described in Section 1.05 of this Specification. The test shall be conducted by the
Contractor in the presence of the City Inspector or Engineer.
Each rehabilitated manhole which fails the test shall be carefully inspected to determine the problem,
resealed as needed, and retested until the manhole passes the vacuum test. For existing manholes
in which a new main is connected, Contractor shall test the manhole once the penetration has been
sealed, and report back to the City Inspector or Engineer the test results. If the existing manhole fails
the test, the City may direct the Contractor to rehabilitate and retest the manhole as part of additional
work.
1.09 MANHOLE ABANDONMENT
Where a manhole is to be abandoned within the street, the Contractor shall break the bottom of the
manhole and remove the frame, cover, taper and barrel sections. The manhole shall be filled with 1-
1/2 sack slurry. Where a manhole is to be abandoned within native soil, the Contractor shall break the
bottom of the manhole and remove the frame, cover, taper and barrel sections and fill the manhole
with ¾” gravel up to 3-feet below grade and fill the upper 3-feet with native soil compacted to 95% or
better. Pipe connections to the manhole are to be plugged.
END OF SECTION
178
CLEANING AND VIDEO INSPECTION OF SEWER PIPE SECTION 2739
CITY OF PALO ALTO SECTION 2739 PAGE 1
SECTION 2739
CLEANING AND VIDEO INSPECTION OF SEWER PIPE
1.01 SCOPE
This section covers the cleaning and video inspection of sewer pipelines and video processing
software and equipment. The word "clean" in this section is defined as the removal of all
accumulations including sludge, dirt, sand, rocks, grease, roots, and other solid or semisolid material
in the pipe or manhole and on the pipe or manhole inside wall, down to the parent material.
1.02 SUBMITTALS
A. Contractor shall submit NASSCO PACP and/or LACP certificates, as applicable, for the video
operator coding the video.
B. The Contractor shall submit the first 1,000 LF of video inspected by each operator for Engineer’s
review and acceptance, before continuing the work, to ensure the quality and adequacy of the
output.
C. The Contractor shall submit colored-video, audio, and NASSCO condition assessment report for
completed work on USB flash drive, hard drive, or provided through a Cloud platform with the
monthly progress payment requests. The video must be in 19x20 MP4 file format. Work will
not be considered accepted until these items have been received and approved by the Engineer.
1.03 CAMERA OPERATOR QUALIFICATION
Each camera operator shall have a minimum of 1 year of experience in projects televising sanitary
sewer mains and laterals and commenting on observed defects. Each camera technician shall be
NASSCO PACP and/or LACP certified.
1.04 MATERIALS
A. Cleaning Equipment
1. Hydro-Jetting
a. High-Velocity or Hydro-cleaning Equipment shall be truck mounted for ease of
operation. The equipment shall have a minimum of six hundred (600) feet of high-
pressure hose with a selection of two or more high velocity nozzles. Nozzles shall
be capable of producing a scouring action from 15 degrees to 45 degrees in all
designated line sizes. The equipment shall carry its own water tank capable of
holding corrosive or caustic cleaning or sanitizing chemicals, auxiliary engines and
pumps, and hydraulically driven hose reel. All controls shall be located so that the
equipment can be operated above ground. Equipment shall include a high-velocity
gun for washing and scouring manhole walls and floor. The gun shall be capable of
producing flows from a fine spray to a solid stream.
2. Mechanical Cleaning
a. Rodding Machines – Root cutters and porcupines shall be attached to the winches
and be used as necessary to remove roots, grease, and other debris. The
attachments shall be suitable for the type of pipe that is being cleaned. A power
rodding machine shall be either a sectional or continuous-rod type capable of
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CLEANING AND VIDEO INSPECTION OF SEWER PIPE SECTION 2739
CITY OF PALO ALTO SECTION 2739 PAGE 2
holding a minimum of 750 feet (230 m) of rod. The machine shall be fully enclosed
and have an automatic safety clutch or relief valve.
b. Bucket Machines – Bucket machines shall be used in pairs with sufficient power to
perform the work in an efficient manner. Machines shall be belt operated or have an
overload shutoff device. Machines with a direct drive that could cause damage to the
pipe will not be allowed. Bucket machines shall not be used on any host or
rehabilitated pipeline that is lined with a plastic pipe or material.
c. Chemicals – Chemicals made for sanitary sewer use and acceptable to the City’s
Water Quality Control Plant may be used to remove grease and kill roots.
B. Video Inspection
1. Push Camera – The push camera shall have a sonde transmitter. The equipment will be
used in a wastewater pipes with an internal diameter of less than six (6) inches. Small
diameter push camera shall be able to access building cleanouts that are two (2) inches in
diameter.
Both cameras must be able to be traced throughout the entirety of the inspection. The
equipment must have the ability to be located above grade using the sonde locator.
The footage counter for each push-camera must be accurate to 0.5 feet per 100 feet over the
length of the particular section of pipeline being inspected. At the City’s request, the footage
counter shall be replaced if the footage counter produces inspection footage that is outside
the acceptable accuracy.
The equipment lighting must illuminate the entire pipe, but shall not oversaturate the footage
of pipe.
2. Mainline Camera and Lateral Launch – CCTV system equipment shall include television
cameras, a television monitor, cables, power sources, and other equipment. The mainline
camera equipment shall include a multi-angle television camera capable of spanning 360
degrees circumference and 270-degrees on the horizontal axis to televise sewer lines 6-
inches in diameter or larger; the purpose of the rotating head camera is to view all service
connections, upstream and downstream manhole structures, and to locate all defects, as
well as questionable problem areas; focal distance shall be adjustable through a range of
one (1) inch to infinity. The television camera shall be color format and specifically designed
and constructed for operation in connection with sewer inspection and for operation in
sewers less than 100% humidity conditions. Lighting and camera quality shall produce a
clear, in-focus picture of the entire periphery of the pipe for a minimum distance of six feet.
Other required equipment includes television monitor, cables, power sources, lights, and
other equipment necessary to do the work. The remote-reaching footage counter shall be
accurate to 0.5 feet per 100 feet over the length of the particular section of pipeline being
inspected. The camera equipment shall have a sonde transmitter and have the ability to be
located above grade.
3. Video Processing System – The video processing system shall be the software system
Granite XP, as used by the City, or a compatible database format system that can use the
existing generic connector to convert to a Granite XP format. Video format shall be .MP4 and
files shall be exported in PACP database format. Contractor shall provide a composite PACP
video report that includes comment/defect code and footage with each associated still
picture. Video Codeset – Video codeset shall be PACP 4.2, 4.4, or 6.0 formatted data.
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1.05 VIDEO INSPECTION AND CLEANING
Pre-Construction:
For all water, gas, and wastewater CIP projects, the contractor shall perform pre-construction
cleaning and video inspection of existing wastewater pipelines to identify active sewer laterals. Prior
to performing sewer main pipe-bursting operation, the Wastewater CIP contractor shall also perform
pre-construction cleaning and video inspection of existing sewer mains and laterals to verify no cross-
bore is present and to identify/evaluate sags in the existing sewer main and discuss with the
Engineer to determine whether spot repair is required. Refer to Section 2739, 1.05 B Obstructions
and Cleaning. The cost for pre-construction cleaning and video-inspecting work shall be included in
one or more bid items.
Post-Construction:
For water and gas utilities installed by drilling or other trenchless installation method, the contractor
shall perform post-installation video inspection of sewer mains and laterals to verify that there is no
cross-bore present. For wastewater CIP projects, the contractor shall perform post-installation
cleaning and video-inspection of the newly installed sewer mains. The cost for post-construction
cleaning and video-inspecting work shall be included in one or more bid items.
A. Video Inspection
1. Wastewater Main Video Inspection – Depth of flow shall not exceed twenty percent (20%) of
the inside pipe diameter as measured in the manhole when performing video inspection. In
the event the depth of flow of the reach being televised exceeds twenty percent (20%) of the
inside pipe diameter, the Contractor shall monitor the sanitary pipes to be inspected to
determine video inspection schedule or to provide the necessary flow control or reschedule
the inspection for a time when such flow is reduced to permit proceeding with the work. If
nighttime work is necessary, the Contractor shall obtain a "Noise Exception Permit" from the
CPA Planning & Development Services (285 Hamilton Avenue, Palo Alto, CA 94301).
The video shall start outside the manhole and end inside the end structure capturing video of
both structures prior to setting the start footage, and after the footage is stopped. The
camera shall be moved through the pipeline in either direction at a uniform rate, stopping
when necessary to ensure proper documentation of the sewer's condition. In no case shall
the television camera be pulled or propelled at a speed greater than thirty (30) feet per
minute. The camera height shall be adjusted such that the camera lens is always centered
in the pipe being inspected. The equipment shall have an accurate footage counter, which
shall display on the monitor the exact distance of the camera from the centerline of the
starting manhole. Unless otherwise approved by the Engineer, footage measurements shall
begin at the centerline of the upstream manhole.
The video inspection shall follow PACP and/or LACP formatting that includes the
documentation that describes the inspection location and other parameters associated with
the inspection. Data of significance includes, but is not limited to, the locations of service
connections, types of upstream and downstream manhole structures, and any pipe defects.
Footage shall be imbedded in the video (Granite XP) or burned on the video in addition to
other footage indicators or recorded events. If the recordings are of such poor quality that
the Engineer is unable to evaluate the condition of the sewer, locate sewer service
connections, or verify cleaning, the Contractor shall re-televise the sanitary sewer and
provide a new recording of good quality at no cost to the City. No payment will be made for
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recordings that do not meet the requirements of these specifications.
2. Wastewater Lateral Video Inspection – Where inspection cannot be completed using a
lateral launcher, the Contractor shall use a push camera to complete the inspection. The
push camera is inserted at a cleanout and is moved downstream toward the wastewater
main.
If branched laterals are encountered, the Contractor shall attempt to locate cleanout of the
branched lateral to access for inspection.
If a cleanout is not available, the Contractor may request City-approval to perform push
camera inspections through a roof vent. The contractor must provide the appropriate
equipment to perform push camera inspection from the roof vent. This includes ladders,
harnesses, and any other equipment required to safely perform the push camera inspection.
The Contractor is responsible for any damages occurred during inspection through a roof
vent and the safety of their employees. The Contractor shall not enter the property of the
occupant nor access the roof vent without the presence of the City Inspector.
B. Obstructions and Cleaning
Where an obstruction such as roots, debris, deposits, fat, oil or grease is encountered and
prevent the camera inspection equipment from capturing complete footage of the wastewater
pipe, the Contractor shall perform high-velocity hydraulic cleaning to attempt to remove the
obstruction. The Contractor shall attempt a minimum of 2 passes with the hydraulic nozzle unless
otherwise approved by the Engineer.
For wastewater mains that cannot be cleaned by hydraulic cleaning from one manhole, the
equipment shall be moved and set up at the other manhole and cleaning shall be re-attempted to
remove the debris. If successful removal of the debris cannot be performed or the equipment
fails to traverse the entire pipeline section, it shall be assumed that a major blockage exists.
Where there is a major blockage preventing its removal, the Contractor shall notify the Engineer
and remove the obstruction by a method approved by the City.
For wastewater laterals, obstructions shall be attempted to be removed by hydraulic cleaning
shall only be performed in the downstream direction toward the wastewater main. If the
obstruction cannot be removed by hydraulic cleaning, the Contractor shall notify and provide a
still-image of the obstruction to the Engineer. The obstruction shall be removed by excavation,
repair, or other means approved by the Engineer.
If a sag prevents the complete inspection of a wastewater pipe, the Contractor shall inspect from
the downstream point of connection and from the upstream access point to verify that a sag is
present. Where the sag is present, the Contractor shall be required to remove the section of pipe
that has a sag and replace it to the nearest joint. If the method of pipeline replacement is pipe
bursting and total number of sags along a wastewater main, between two manholes, are
encountered exceed three (3), the Contractor shall replace the wastewater main by open trench
excavation.
Where roots or a root ball are encountered that cannot be removed by hydraulic cleaning, the
Contractor shall excavate at the location of the roots or root ball and perform a point repair of the
pipeline if pipe bursting or lining shall be performed. Roots shall not be a reason for reverse set-
up. Special attention should be used during the cleaning operation to ensure complete removal
of roots from joints of pipelines that are 33-inches or smaller. For pipes 36-inches in diameter or
larger, the Contractor shall remove 90 – 95% of roots from pipe joints.
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Where a protruding lateral prohibits the Contractor from performing a lateral launch, the
Contractor shall notify the City Inspector and provide a still-image of the protruding lateral to
Utilities Engineering. The still-image will be forwarded to Utilities Operations and its removal will
be scheduled. The Contractor will be notified when the protruding lateral is removed.
If a suspected cross bore is encountered, the Contractor shall notify the Engineer and provide a
still-image of the cross bore encountered to the City. Utilities Operations will be notified to
schedule the necessary repairs and the Contractor shall be notified of when the repairs are
completed.
Mechanical cleaning is not permitted on plastic pipes and will only be permitted after the pipe has
been cleared of cross bore(s).
Debris removed from the pipeline(s) as a result of cleaning shall be removed from the
downstream manhole receiving flow from the pipeline(s) cleaned. Prior to analysis and disposal,
debris shall be captured using a filtering device. Such materials collected at the downstream
manhole shall become the responsibility of the Contractor, removed from the site by the
Contractor in a closed container, and disposed of in accordance with Federal, State, and local
laws and regulations at an appropriately classed landfill. The debris collected by the Contractor
shall not be dumped into streets, ditches, catch basins, or storm sewers. Flushing of the material
from manhole reach to manhole reach is prohibited.
Acceptance of the sewer line cleaning shall be made upon the successful completion of the video
inspection and shall be to the satisfaction of the Engineer. If video inspection shows the cleaning
to be unsatisfactory, the Contractor shall be required to re-clean and re-inspect the sewer main
at no additional cost to the City.
END OF SECTION
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SECTION 2740
SURVEY DATA COLLECTION
1.01 BASIS OF SURVEY CONTROL
The City of Palo Alto has established a GPS Control Network and survey control monuments
throughout the City to be used as the official survey control benchmarks. All surveying and
engineering related work shall use these monuments in order for the projects to be incorporated into
the City's GIS mapping. To satisfy the City of Palo Alto horizontal coordinate & vertical datums, the
surveyor must tie the requested work to the City GPS control monuments prepared by Bestor
Engineers in 1994 and submit your northings and eastings in the City’s coordinate system. The City
will not accept deliverables in other coordinates systems and/or own local ("project") coordinate
systems.
The coordinates shown on the record of survey are based on the North American Datum of 1983
[NAD 83(1992 epoch)] in the California State Plane Coordinate System, (zone 3) in units of survey
feet. Vertical elevations are based upon the NGVD 29 as per the USC&GS adjustment of 1967.
Additional information concerning elevations and secondary vertical control benchmarks to be used
for vertical control only is on file and available at the City of Palo Alto Public Works engineering
surveying office. The data provided by Public Works is intended to be used as a reference.
Horizontal and vertical control reference point data is available upon request. Copies of full size of
the Record of Survey and Survey Control Monument maps prepared by Bestor Engineers, Inc. dated
February 1994 are available at the Utilities Engineering Office.
Per submittal requirement prior to construction commencement, the contractor shall submit
coordinate text files (PNEZD) of all survey control monuments needed to perform the survey work for
the City to validate its accuracy and delivery in the City’s coordinate system.
A California Licensed Land Surveyor is responsible to setup all control points needed to perform the
survey work. The accuracy for all survey data shall be +/- 0.5 in; with an exception of gas meter risers
on private properties to be +/- 0.5 ft. For CIP pipeline replacement projects, all survey data collected
shall be certified by a California Licensed Land Surveyor.
Per submittal requirement prior to construction commencement, the contractor shall submit
coordinate text files (PNEZD) of all necessary survey control monuments for the City to validate its
accuracy and delivery in the City’s coordinate system. Use CPAU WGW Engineering’s "feature
codes" for naming convention and refer to the feature capture-positions in the ‘Feature Codes and
Feature Capture-Positions’ table at the end of this section.
In addition, the Contractor shall submit the GPS data set collected for the installation work during the
first week of construction for the City to validate its accuracy. The completeness and accuracy of
GPS survey data shall be verified by the City before the issuance of each payment to the contractor.
For CIP projects, the City of Palo Alto may require the Contractor, at Contractor’s own expense, to
reopen or uncover GPS surveyed infrastructure/objects and perform new survey if the accuracy of
the originally submitted data is not in compliance with these specifications or the data is not collected
in open-hole. The Contractor will be required to perform surface restoration, at the Contractor’s own
expense, following the additional survey.
When applicable, survey data shall be collected within the entire width of the street and on private
properties to include all features identified in Table 2. The extents of the survey area shall cover the
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full intersections to curb returns. The consultant/contractor shall obtain approval from business/home
owners or occupants to access private properties for collecting required survey data. No additional
compensation will be made for delays due to private property accessing issues. The
Consultant/contractor shall provide necessary traffic control to meet the CPA Transportation
Department’s standards. No additional compensation will be made for traffic control on major streets.
1.02 SURVEY DATA COLLECTION
A. Deliverables
1. Prior to construction commencement - Northing and easting coordinate text files (PNEZD) of
all control survey points needed to perform the survey work in .csv format, including feature
code of each point in the spreadsheet.
2. Northing and easting coordinate text files (PNEZD) of survey points for all new utility features
installed during the first week of construction in .csv format, including feature code and
description (if applicable - in same column), of each point in the spreadsheet.
3. Survey data in .csv format with benchmarks, surveyed points, and feature codes shall be
submitted monthly or with each progress payment request. Refer to Section 800 Additional
Provisions for additional requirements for Utilities CIP Projects. Payment will be made on the
percentage of total project completed, submitted, and accepted.
B. Data to be collected (See table 2 for feature capture-position)
1. Sanitary Sewer Rehabilitation Projects
a. Collect horizontal and vertical data for:
i. Sanitary sewer manholes.
1. Lid (center)
2. Depth
3. Invert elevations for each pipe
4. In/out directions for each pipe relative to magnetic North.
ii. Lateral connections to mains (at the top of the pipes, to be collected in open holes
during construction [i.e. prior to backfilling]).
iii. Changes in pipe alignment (at the top of the pipes, to be collected in open holes
during construction [i.e. prior to backfilling]).
b. Collect horizontal data for:
i. Lateral cleanouts
2. Water Main Replacement Projects
a. Collect horizontal and vertical data for:
i. Water valves, including all main line valves, service valves, fire hydrant valves, and
blow off valves.
ii. Service connections to mains (at the top of the pipes, to be collected in open holes
during construction [i.e. prior to backfilling]).
iii. Tapping tees for all water connections (at the top of the tee, to be collected in open
holes during construction [i.e. prior to backfilling]).
iv. Main and service reconnection points (at the top of the fitting or pipe, to be collected
in open holes during construction [i.e. prior to backfilling]).
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v. Changes in pipe alignment (at the top of the pipes, to be collected in open holes
during construction [i.e. prior to backfilling]).
vi. Fittings, including couplings, reducers, elbows, sleeves, caps and line stops (at the
top of the fittings, to be collected in open holes during construction [i.e. prior to
backfilling]).
vii. Anode boxes (typically installed near fire hydrants).
b. Collect horizontal data for:
i. Fire hydrants
ii. Air release valves
iii. Water meters
iv. Sewer manholes (for data validation purpose)
3. Gas Main Replacement Projects
a. Collect horizontal and vertical data for:
i. Gas valves, including all main line, service, and excess flow valves.
ii. Service connections to mains (at the top of the pipes, to be collected in open holes
during construction [i.e. prior to backfilling]).
iii. Tapping tees for all gas connections (at the top of the tee, to be collect in open
holes during construction [i.e. prior to backfilling]).
iv. Changes in pipe alignment (at the top of the pipes, to be collected in open holes
during construction [i.e. prior to backfilling]).
v. Fittings, including couplings, transition fittings, reducers, elbows, end caps, etc., to
be collected in open holes during construction [i.e. prior to backfilling]).
b. Collect horizontal data for:
i. Anode boxes
ii. Gas meters
iii. Gas meter curbs
iv. Gas risers (end of riser or at ground penetration)
v. Sewer manholes (for data validation purpose)
4. Miscellaneous Development Service Projects and Survey Contracts
a. Collect horizontal and vertical data for:
i. Sanitary sewer manholes.
a. Lid (center)
b. Depth
c. Invert elevations for each pipe
d. In/out directions for each pipe relative to magnetic North.
ii. Storm drain manholes, catch basins, culverts and inlets.
a. Lid (center); catch basin, culvert, inlet (top center at inlet)
b. Depth
c. Invert elevations for each pipe
d. In/out directions for each pipe relative to magnetic North.
iii. All gas and water valves.
iv. Street Surface along the crown of the pavement (i.e. along the approximate
centerline of the street width) at grade breaks and every 50’ maximum.
b. Collect horizontal data for: (collect data at center of manholes, lids, and boxes unless
otherwise noted.)
i. Electrical/Fiber Optic/Telephone manholes and boxes
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ii. Fire hydrants
iii. Anode boxes
iv. Air release valves
v. Water and gas meters
vi. Lateral cleanouts
vii. Main cleanouts
viii. Lampholes
ix. Flush inlets
x. Gas risers (at ground penetration)
xi. Front and back of sidewalk, face of curb, lip of gutter and edge of pavement on both
sides. For linear alignment collect data at both ends of the block. For non-linear
alignment collect data at every turning point.
xii. Monuments
See Table 2 for each feature description, feature code and feature capture-position for the survey
data that is being requested.
Table 2: Feature Codes and Feature Capture-Positions
Feature Description Feature Code Feature Capture-Position
SURVEY REFERENCE POINT
Benchmark BM
Back Site Point BSPT
ROAD FEATURES
Back of Curb BOC Back of curb
Back of Rolling Curb BORC Back of rolling curb
Bridge, Edge BREDGE Edges of bridge outline
Back of Sidewalk BSW End pts. on straight alignment & every turning pt.
Back of Valley Gutter BVG At flow line
Crown of Street CROWN End pts. on straight alignment & every turning pt.
Ditch DITCH At flow line
Driveway DWY Edge of driveway both sides
Edge of Pavement EOP Both ends of the block and every turning pt.
Fence FENCE End pts. on straight alignment & every turning pt.
Flow Line FL End pts. on straight alignment & every turning pt.
Face of curb FOC End pts. on straight alignment & every turning pt.
Lip of Gutter LOG End pts. on straight alignment & every turning pt.
Loop Detector LOOPDE As needed
Street Monument MONSTR Center of lid/cover
Swale at Flow Line SWALE As needed
Traffic Speed Control TRSPCN As needed
Traffic Speed Donut TRSPDON As needed
Street Turn Around TURNARO As needed
Guard Rail GUARDR As needed
Parking Lot PARKING Edges of parking lot
Speed Bumps SPEEDB As needed
BUILDING
Building BLDG Building corners
WATER
Air Relief Valve WTARV Center of valve
Detector Check Valve WTDCV Center of valve
Fire Hydrant WTFH Center of hydrant
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Water Main WMAIN End pts. on straight alignment & every turning pt.
Water Main Tapping Tee WTTEE Service connection point to main
Water Service WTSVC End pts. on straight alignment & every turning pt.
Water Service Saddle WTSDL Center top of main at service connection
Water Valve - Main WTVMAIN Center of lid/cover and stem
Water Valve - Service WTVSVC Center of lid/cover and stem
Water Valve - Fire Hydrant WTVFH Center of lid/cover and stem
Water Valve - Blow-Off WTVBO Center of lid/cover and stem
Water Meter WTM Center of meter
Miscellaneous Fittings:
Coupling WTCPL Center of fitting
Horizontal Elbow 11 WTELB11 Center of fitting (point of turn) 11 degrees
Horizontal Elbow 22 WTELB22 Center of fitting (point of turn) 22 degrees
Horizontal Elbow 45 WTELB45 Center of fitting (point of turn) 45 degrees
Horizontal Elbow 90 WTELB90 Center of fitting (point of turn) 90 degrees
Vertical Elbow 11 WTELBV11 Center of fitting (point of turn) 11 degrees
Vertical Elbow 22 WTELBV22 Center of fitting (point of turn) 22 degrees
Vertical Elbow 45 WTELBV45 Center of fitting (point of turn) 45 degrees
Vertical Elbow 90 WTELBV90 Center of fitting (point of turn) 90 degrees
Reducer WTRDC Center of fitting
Sleeve WTSLV Center of fitting
Cap WTCAP Center of fitting
Line Stop WTLS Center of fitting
Anode Box WTANOBOX Center of lid/cover
GAS
Existing Anode Box ANOBOX Center of lid/cover
Gas Meter GM Center of meter
Gas Meter Curb GMCURB Center of meter
Gas Riser GRISER Front of riser perpendicular to main
Gas Main GMAIN End pts. on straight alignment & every turning pt.
Gas Main Tapping Tee GTEE Service connection point to main
Gas Service GSVC End pts. on straight alignment & every turning pt.
Gas Valve - Main GVMAIN Center of lid/cover and stem
Gas Valve - Service GVSVC Center of lid/cover and stem
Miscellaneous Fittings:
Coupling GCPL Center of fitting
Horizontal Elbow GELB Center of fitting ( point of turn)
Vertical Elbow GELBV Center of fitting ( point of turn)
Reducer GRDC Center of fitting
Sleeve GSLV Center of fitting
Cap GCAP Center of fitting
Line Stop GLS Center of fitting
WASTEWATER
Wastewater Main WWMAIN End pts. on straight alignment & every turning pt.
Wastewater Main Tapping Tee WWTEE Lateral connection point to main
Wastewater Lateral WWLAT End pts. on straight alignment & every turning pt.
Wastewater Clean Out WWCO Center of lid/cover
Wastewater Flushing Inlet WWFI Center of lid/cover
Wastewater Lamp Hole WWLH Center of lid/cover
Wastewater Manhole WWMH Center of lid/cover, depth, invert elevations and
in/out directions relative to magnetic north
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ELECTRIC
Electrical Vault 1,2,3,4 Lids ELVLT Center of vault
Electrical Manhole EMH Center of lid/cover
Fiber Optic Manhole FMH Center of lid/cover
Fiber Optic Vault FVAULT Center of vault
Telephone MH TELMH Center of lid/cover
Telephone Vault TELVAULT Center of vault
STORM DRAIN
Box Culvert BOXCLV Center line
Catch Basin CB Center of grate, depth, invert elevations and
in/out directions relative to magnetic north
SD Headwall SDHW As needed
SD Inlet SDIN As needed
SD Manhole SDMH Center of lid/cover, depth, invert elevations and
in/out directions relative to magnetic north
1.03 CONSTRUCTION STAKING FOR CIP PROJECTS
The Contractor shall be responsible for construction staking of open trench construction and marking
proposed pipeline alignment per project plans for CIP projects. All survey work for construction
staking shall be performed by a California Licensed Land Surveyor. The surveyor is responsible to
setup all control points needed to perform the survey work.
END OF SECTION
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SECTION 2741
LEGACY CROSS BORE INSPECTION GUIDELINES
PART 1 – GENERAL
1.01 DESCRIPTION
This section covers the video inspection of sewer laterals installed by trenchless methods to locate
cross bore and submission of Lateral Assessment and Certification Program (LACP) as per National
Association of Sewer Service Companies (NASSCO) Standards.
LACP reports should only be submitted for the City-owned portion of the laterals (lower sewer lateral).
Only crossbore-inspection videos should be submitted for the private sewer laterals (upper sewer
lateral) including laterals in private easements or non-City-owned laterals.
“Cross bore” is an unintended conflict between natural gas service pipelines and sanitary sewer
laterals.
1.02 RELATED WORK
Section 01500 Traffic Control
Section 02200 Excavation, Backfill, and Restoration
PART 2 -- MATERIALS
2.01 EQUIPMENT
A. CAMERA
The equipment shall include full-color video cameras, video monitor cable, power sources, and all
necessary equipment to perform a complete CCTV video inspection of sanitary sewer laterals. The
camera equipment shall meet the California Division of Occupational Safety and Health for Electrical
Sewer Inspection Camera Sections 2340.11 (Water Safety) and 2540.2 (Fire Safety) for performing
inspections within wastewater facilities.
1. LATERAL LAUNCHER
The lateral launcher shall have a sonde transmitter. The equipment shall perform remote-
controlled inspections in most sewer laterals with wastewater main pipelines having an
internal diameter equal to six (6) inches to no larger than forty-two (42) inches. The
equipment should be capable of working within large diameter pipes which often require
special procedures for flow control, lighting, and camera travel. Lateral launch cameras shall
have a steering arm to provide navigation through wyes and tees in the sewer lateral.
2. PUSH CAMERA
The push camera shall have a sonde transmitter. The equipment will be used in a wastewater
pipeline or sewer lateral with an internal diameter of less than six (6) inches. A small diameter
push camera shall have the ability to enter through building cleanouts that are two (2) inches
in diameter.
Both cameras used must be able to be traced throughout the entirety of the inspection. The
equipment must have the ability to be physically located from above grade through a sonde
locator.
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The footage counter for both cameras must be calibrated during video inspection and must
be accurate to 0.5 feet per 100 feet. At the City’s request, the Contractor may be required to
replace the footage counter to capture accurate counter readings. The travel speed should
be a uniform rate of no more than thirty (30) feet per minute. The equipment should be slower
when recording features and defects of the City-owned sewer lateral (lower sewer lateral).
The lighting of the equipment shall fully illuminate the entire pipe but shall not oversaturate
the footage of pipes. The operator shall ensure that the camera and video show a correct
reflection of the true colors within the pipe and on the video display. The camera lens shall
be kept clear of condensation and debris and shall be able to operate in one hundred percent
(100%) humidity.
B. WATER JETTER
1. The Contractor shall perform water jetting services if a blockage prevents complete
inspection of the pipe. Water jetting will be initiated via the cleanout.
2. The equipment should not have a saw or a cutting head attached.
3. The equipment must have a minimum capability of providing a 2,000 psi and a maximum of
4000 psi (pounds per square inch) of water pressure and a maximum output of 18 gallons
per minute.
4. The equipment must have a minimum of 1,500-gallon water tank.
C. HYDRO – EXCAVATION
1. The equipment must have a minimum capability of providing a 2,500 psi force of water with
rotating digging tips.
2. The equipment must have a minimum of 1,500-gallon water tank.
D. CLEANOUT PLUG WRENCH
1. The Contractor shall utilize a cleanout plug wrench to remove cleanout lids and avoid damage
to cleanout plugs. The Contractor shall be responsible for repairing any damages caused by
their forces to cleanouts. The Contractor is required to bring extra cleanout covers/plugs of
varying sizes to replace damaged cleanout covers/plugs during the inspection.
PART 3 – QUALIFICATIONS, TESTING, AND INSPECTION
3.01 OPERATOR QUALIFICATIONS
The Contractor shall have participated in a minimum of 1,000 sewer lateral inspections associated
with a gas cross bore inspection program.
The lower sewer lateral shall be assessed by a certified NASSCO Lateral Assessment and
Certification Program (LACP) trained operator or technician.
3.02 INSPECTION
A. HEALTH
1. The Contractor performing the push-camera inspection shall wear proper PPE such as
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disposable gloves and safety glasses.
B. LATERAL LAUNCHER
2. The lateral launcher must have the capability of traversing a minimum of 150 feet.
3. The video inspection must begin from the wastewater main pipeline to the foundation of the
structure or extend three (3) feet beyond the furthest gas riser.
C. PUSH CAMERA
1. Where inspection cannot be completed using a lateral launcher, the Contractor will use a
push camera to complete the inspection or vice versa. The push camera is inserted at
cleanout and travels toward the wastewater main pipeline.
2. If branched laterals are encountered and identified as a location that cross the gas service
pipeline, the push camera will be initiated via an accessible cleanout to successfully clear the
branch lateral.
3. If a cleanout is not available, the Contractor may request City-approval to perform push
camera inspections through a roof vent.
a. The Contractor must provide the appropriate equipment to perform the push camera from
one to two stories above the grade. This includes ladders, harnesses, and any other
equipment required to safely perform the push camera inspection.
b. The Contractor is responsible for any damages that occurred during inspection through
a roof vent and the safety of their employees.
c. The Contractor shall not enter the property of the occupant nor access the roof vent of
the house or the building without the approval from the Project Engineer and the
presence of the City Inspector.
4. If a backwater valve is encountered in the sewer lateral, the Contractor may attempt to
inspect the sewer lateral by using a small diameter push camera, only if equipment damage
is unlikely and not limited by the backwater valve design configuration.
D. WATER JETTING AND MECHANICAL CLEANING
1. If an obstruction such as roots, debris, deposits, fat, oil, and grease prevents lateral launching
or using a push camera, the Contractor will perform hydro flushing as needed to allow
passage of the inspection camera and to capture acceptable quality video.
2. The Contractor will be responsible for providing all backpressure and backflow preventive
measures and equipment.
3. The Contractor will be responsible for all damages associated with sewer backup caused by
their cleaning activities.
4. The Contractor shall immediately notify the City in the event of any Sanitary Sewer Overflow
(SSO) associated with their cleaning activities. The Contractor is responsible for all costs
associated with the proper cleanup of SSO.
5. The City will not be responsible for the pre-cleaning of the wastewater mains. Therefore, the
Contractor may be required to pre-clean the wastewater main prior to sewer lateral
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inspection.
E. HYDRO – EXCAVATION
1. If sag sections of sewer lateral are found during video inspection or if the sewer lateral cannot
be inspected in the potential cross bore area:
a. The Contractor must locate the alignment of the sewer lateral and gas service line using
sonde devices and pipe locator, respectively.
b. If the shortest distance between the gas service line and the sewer lateral is within three
(3) feet, the Contractor will perform potholing to determine if a potential cross bore exists.
2. Where gas pipelines cross branched laterals or wyes, the Contractor shall pothole at the
downstream point of connection to perform a video inspection of the branched lateral when
a push camera cannot be used to complete video inspection, see Figure 1.
WW Main
Gas Main
sewer lateral
branched lateral
gas service line
sewer cleanout
perform pothole
Gas service line cross branched laterals
Figure 1
3. The Contractor shall refer the Water, Gas, & Wastewater Utility Standards for excavation,
backfill, and restoration.
4. The Contractor shall only perform the potholing in the presence of the City Inspector.
5. The Contractor shall follow all established safety procedures as per CAL OSHA for digging
around underground utilities.
F. SURFACE MARKING
1. The Contractor shall place marking chalk or paint on paved surfaces and flags or feathers on
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unpaved surfaces. The Contractor shall remove the markings placed by their forces.
2. Surface markings shall be placed at a maximum of five (5) foot intervals and at all locations
where there is a change in horizontal direction exceeding fifteen degrees (15o) when
locating the alignment of the sewer laterals and gas service pipelines.
3. All Underground Service Alert (USA) markings requested by the Contractor shall be
removed by the Contractor.
G. PIPE CONDITION
1. If severe pipe conditions exist such as root balls, broken pipe, and offset joints that prohibit
complete video inspection, the Contractor shall notify the City Inspector who shall determine
if it is on the City-owned lateral side or private lateral side.
a. Lower sewer lateral side - The Contractor and City Inspector shall notify CPAU
Engineering for repair.
b. Upper sewer lateral side – The Contractor and City Inspector shall notify CPAU
Engineering to provide notice to the property owner or representative.
2. Where a sag is encountered, the Contactor shall video inspect the sewer lateral from the
downstream point of connection and from the upstream access point to verify that a sag is
present. The Contractor shall pothole at the location of the sag to determine if a cross bore
exists.
3. Where a root ball is encountered, the Contractor shall hydro-flush the sewer pipe if it is
within 3-feet of the location of a gas pipe, to the satisfaction of the City Inspector. If the root
ball cannot be removed, the Contractor shall attempt to perform a reverse inspection.
Where a reverse inspection cannot be performed by the Contractor, the Contractor will be
required to hydro-excavate to determine if there is a cross bore at the location of the root
ball.
4. If the depth of flow exceeds 20% of the inside pipe diameter, the Contractor shall monitor
the sanitary pipes. If there is evidence the sanitary has low-flow conditions (≤ 20%) and
upon City approval, the Contractor would be permitted to adjust working hours. If high-flow
conditions (> 20%) persist, the Contractor will be requested to provide the necessary flow
control. Where flow control is required, the Contractor shall not plug pipes with the diameter
of 12-inches or larger.
5. Where a protruding lateral prohibit the Contractor from performing lateral launch, the
Contractor shall notify the City Inspector and provide a still-image of the protruding lateral
to CPAU Engineering. The still-image will be forwarded to CPAU Operations and its
removal will be scheduled. The Contractor will be notified when the protruding lateral is
removed.
H. INSPECTOR
1. The City Inspector will be on-site during all sewer lateral inspections.
2. The City Inspector will determine the necessary distance to safely clear the sewer lateral of
any potential cross bore.
3. The completion of a sewer lateral inspection will be left up to the discretion of the City
Inspector. If a sewer lateral inspection is complete, the Contractor shall not move to the next
inspection until instructed by the City Inspector.
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4. The Inspector will verify the correct property to be inspected based on the package provided
to the Contractor.
I. PROXIMITY CLEARANCE
1. Upon City approval, the Contractor will be permitted to clear sanitary pipes by proximity if
other methods of inspection are unable to be performed.
J. EFFORT EXHAUSTED
1. The Contractor must exhaust all efforts as directed by the Engineer to determine if a cross
bore exists when existing conditions prevent the full inspection of the complete lateral.
2. If all attempts to video inspect the sewer lateral are unsuccessful and a proximity clearance
cannot be performed, the Contractor shall report the reason for effort exhausted to the City
after the last inspection attempt.
3. The Contractor will NOT be compensated for effort exhausted.
K. IDENTIFIED CROSS BORES
1. If an apparent cross bore is discovered, the Contractor shall take a still-image of the cross
bore location and submit it to the City Inspector for it to be included as a part of the daily
report and submit the Contractor’s Zoho form with the photo of the cross bore. The Inspector
will notify CPAU Engineering.
2. The Contractor shall mark the surface location of the apparent cross bore with marking paint.
a. If the gas pipe conflicting with the sewer pipe does not impede the inspection camera
and does not damage the gas pipe, the Contractor can continue inspection of the
sewer pipe until the video inspection is completed.
b. If the gas pipe conflicting with the sewer pipe impedes the inspection camera, the
Contractor shall stop the video inspection and notify the City Inspector.
3. CPAU Engineering will inform CPAU Operations and Maintenance to investigate the cross
bore.
4. Where a cross bore is found, CPAU Operations and Maintenance will schedule the
necessary repairs.
5. After the cross bore is repaired, the Contractor shall remobilize and resume the video
inspection work until it’s successfully completed.
L. REPORTING
1. The Contractor shall encode the condition assessment as per the NASSCO Standard of the
City-owned sewer lateral (lower sewer lateral) and electronic images of the sewer lateral
condition. The report will also include documentation of the footage traveled during sewer
lateral inspection.
2. The Contractor shall fill out and provide a Zoho Form report for cross bores and reasons for
an incomplete inspection with inspection pictures attached to the form.
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3. If there are wyes or branched laterals encountered during inspections, the Contractor shall
document the inspection footage traveled in each wye or branched lateral.
4. A video of the inspection for each sewer lateral must be submitted by the Contractor. The
video must be in 19 x 20 MP4 file format.
5. All reports must be in PDF format.
6. All lateral launch and push camera videos and corresponding reports for the main lateral
shall be named the following:
Video Name:
“StreetName_House#_FID_MMDDYYYY” for one complete video of both the Private
lateral and City lateral.
OR
“StreetName_House#_FID_MMDDYYYY_PVT” and
“StreetName_House#_FID_MMDDYYYY_CITY” for two separate video reports of the
Private lateral and City Lateral
Report Name: “NASSCO_StreetName_House#_FID_MMDDYYYY”
For branched laterals or wyes from the main lateral requiring inspection (each address), the
videos and reports shall be labeled the following:
“StreetName_House#_FID_BL# or W#_MMDDYYYY_PVT”
7. All NASSCO and video reports shall be submitted at the end of each week to CPAU
Engineering for review.
M. QUALITY ASSURANCE (QA)/QUALITY CONTROL(QC)
1. The Contractor shall provide experienced work crews for data capture.
2. Frequent lens washing and lighting adjustments shall be included in order to obtain
acceptable video quality
3. Videos submitted for payment that exceeds the maximum travel speed will be rejected. The
Contractor will be directed to re-inspect the sewer lateral at no additional cost to the City.
4. The Contractor will provide coding of all City-owned sewer laterals at the time of video
inspection by a NASSCO LACP certified personnel.
5. The camera operator shall assess and shall indicate the status of the City-owned lateral
(lower sewer lateral) using NASSCO-compatible software.
6. In the event that the CPAU Engineering personnel discover a gas cross bore during the video
review, the Contractor will be instructed to re-inspect the sewer lateral at no additional cost
to the City.
7. The City shall reserve the right to cease all Contractor activities when the quality of work is
found to be unsatisfactory.
8. The Contractor shall indicate footage of sewer pipe inspected in deliverables. The footage
counter shall be displayed although out the video inspection.
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9. The Contractor QC personnel shall review one hundred percent (100%) of all video
inspections.
PART 4 – SUBMITTALS
4.01 DELIVERABLES
A. The Contractor will provide the following deliverables on a weekly basis. The deliverables must
be submitted to the CPAU Engineering on the following Monday by 12:00 p.m.
1. Video
a. Acceptable individual video footage for each lower sewer lateral and each upper sewer
lateral. Video files must be submitted through a “cloud” storage online application.
b. Sanitary pipe inspection videos shall only be submitted for sanitary pipes that were
cleared of cross bore by the City Inspector at the time of inspection.
2. Forms
a. PACP Structural and O&M pipe assessment condition grading form for each inspected
lower sewer lateral. If a defect is identified in the lower sewer lateral, an image of the
defect must be included on the form.
b. WWOPS - LACP Checklist form for each lower sewer lateral.
c. Contractor Zoho forms per address inspected. The Contractor Zoho forms shall provide
required information about the inspection (property address, FID, total footage,
inspection details, and necessary pictures, attached to the form, regarding the
inspection)
3. Weekly cross bore spreadsheet for anticipated work. The spreadsheet will be provided by
the City and must be completed by the Contractor.
4. Weekly invoices for completed work to process progress payment. All invoices must be in
CPAU Engineering-approved format. The progress payment will be made at the end of each
month.
B. The Contractor must submit the latest calibration report of their equipment. The equipment must
be calibrated at least annually but may be calibrated at shorter intervals.
C. Upon the City’s request, the Contractor shall submit maintenance records for equipment used for
the inspection of sanitary pipes. The maintenance records include but are not limited to, truck,
generator, camera, etc.
END OF SECTION
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TABLE OF CONTENTS Appendix A General Details
CITY OF PALO ALTO PAGE 1
Table of Contents
Appendix A
General WGW Utility Standard Details
Detail No. Title
WGW-01 Water, Gas & Wastewater Utility Configurations
WGW-02 Trench Backfill
WGW-02B Joint Gas Service Trench with Electrical
WGW-03 Trench Backfill for Shallow Mains
WGW-04 Pipe Casing and Vent Pipe
WGW-05A Residential Bollard
WGW-05B Commercial Bollard
WGW-06 Gas/Water Valve Concrete Collar and Steel Rebar in Existing Street
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ALLOWED FOR RESIDENTIAL SERVICES ONLY
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MARKER DETAIL
NOT TO SCALE
A-
CASING SEAL DETAIL
NOT TO SCALE
A-A-
A-A-
A-A-
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TABLE OF CONTENTS Appendix B Water Details
CITY OF PALO ALTO PAGE 1
Table of Contents
Appendix B
Water Standard Details
Detail No. Title
WD-01A 2” HDPE Water Service (HDPE Main) with 5/8” or 1” Meter
WD-01B 2” HDPE Water Service (Non-HDPE Main) with 5/8” or 1” Meter
WD-01C 1” Copper Water Service Connection (Contaminated Soils)
WD-02A 2” HDPE Water Service (HDPE Main) with 1-1/2” or 2” Meter
WD-02B 2” HDPE Water Service (Non-HDPE Main) with 1-1/2” or 2” Meter
WD-02C 2” Copper Water Service (Contaminated Soils)
WD-03A 4” Thru 10” HDPE (HDPE Main) Domestic/Fire Service Connection
WD-03B 4” Thru 10” HDPE (Non-HDPE Main) Domestic/Fire Service Connection
WD-04 4” and 6” Water Meter Set with 2” By-Pass
WD-05A 2” HDPE Water Service (HDPE Main) with Two 5/8” or 1” Meters
WD-05B 2” HDPE Water Service (Non-HDPE Main) with Two 5/8” or 1” Meters
WD-06A 2” Water Service Manifold (HDPE Main) with Two or Four 5/8” or 1” Meters
WD-06B 2” Water Service Manifold (Non-HDPE Main) with Two or Four 5/8” or 1” Meters
WD-07A 2” HDPE Water Service Tap HDPE Domestic or Fire Service
WD-07B 2” HDPE Water Service Tap Existing Non-HDPE Fire Service
WD-08 Combination Fire/ Domestic Water Service Connection
WD-09 Combination Fire/Domestic Water Service Connection (Multiple Meters)
WD-10 Armorcast Meter Box (30”x48”) with Multiple Headers
WD-11A 3” or Larger Reduced Pressure Principle Assembly – RPPA
WD-11B Parallel Reduced Pressure Principle Assembly
WD-11C Reduced Pressure Principle Assembly – RPPA (3/4”-2”)
WD-12A Reduced Pressure Detector Assembly RPDA For Fire Services and Sprinklers
WD-12B Reduced Pressure Detector Assembly RPDA For Inside Installation
WD-12C Residential Double Check Valve Assembly - DCVA (1”-2”)
WD-13 Thrust Block Table
WD-14 Gate Valve Assembly
WD-15 Fire Hydrant Assembly with HDPE Pipe
WD-16 Fire Hydrant or Service Abandonment
WD-17 Vertical Bends HDPE Pipe Connecting to Non-HDPE Pipe
WD-17A Vertical Bends PVC or DI Pipe Connecting to Non-HDPE Pipe
WD-18 Valve Tie-Back During Construction
WD-19 2” Blow-Off Valve for Dead End HDPE Mains Up to 12”
WD-19A 2” Blow-Off Valve for Dead End Non-HDPE Mains Up to 12”
WD-20 Cut & Cap Existing Main
WD-21 Air Release Valve
WD-22 New Gate Valve (Installation on Exist. Main)
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TABLE OF CONTENTS Appendix C Gas Details
CITY OF PALO ALTO PAGE 1
Table of Contents
Appendix C
Gas Standard Details
Detail No. Title
GD-01A 1” Gas Service with 1” EFV
GD-01B 1” Gas Service with 1-1/4” EFV
GD-01C 2” Gas Service with EFV
GD-01D 2” Gas Service without EFV
GD-02A Residential Diaphragm Gas Meter Clearance 250-800 SCFH
GD-02B Residential Diaphragm Gas Meter Clearance 1,000 SCFH
GD-02C Residential Rotary Gas Meter Clearance 1,100-1,500 SCFH
GD-03A Residential Meter Set Assembly 250-800 SCFH
GD-03B Residential Meter Set Assembly 250-800 SCFH
GD-04A Residential Manifold Meter Set Assembly w/o Bypass 500 SCFH
GD-04B Residential Manifold Meter Set Assembly w/o Bypass 500 SCFH (List of Materials)
GD-04C Residential Manifold Meter Set Assembly w/ Bypass 1,000 SCFH
GD-04D Residential Manifold Meter Set Assembly w/ Bypass 1,000 SCFH (List of Materials)
GD-05A Residential/Commercial Manifold Meter Set Assembly Up To 1,250 SCFH
GD-05B Residential/Commercial Manifold Meter Set Assembly Up To 1,250 SCFH (List of Materials)
GD-06A Residential/Commercial Manifold Meter Set Assembly 1,500 - 3,000 SCFH
GD-06B Residential/Commercial Manifold Meter Set Assembly 1,500 - 3,000 SCFH (List of Materials)
GD-07A Residential/Commercial Manifold Meter Set Assembly 3,000 - 5,000 SCFH
GD-07B Residential/Commercial Manifold Meter Set Assembly 3,000 - 5,000 SCFH (List of Materials)
GD-08A Residential/Commercial Manifold Meter Set Assembly 5,000 to 15,000 SCFH
GD-08B Residential/Commercial Manifold Meter Set Assembly 5,000 to 15,000 SCFH (List of Materials)
GD-08C Residential/Commercial Manifold Meter Set Assembly 5,000 to 15,000 SCFH (Est. Pressure Loss)
GD-09A Residential/Commercial/Industrial Rotary Meter Set Assembly 800–2,000 SCFH
GD-09B Residential/Commercial/Industrial Rotary Meter Set Assembly 800–2,000 SCFH
GD-09C Residential/Commercial/Industrial Rotary Meter Set Assembly 800–2,000 SCFH
GD-10A Commercial Meter Set Assembly 250 - 425 SCFH
GD-10B Commercial Meter Set Assembly 250 – 425 SCFH
GD-11A Commercial Meter Set Assembly 630-800 SCFH
GD-11B Commercial Meter Set Assembly 630-800 SCFH
GD-12A Commercial Meter Set Assembly 1,000 SCFH
GD-12B Commercial Meter Set Assembly 1,000 SCFH
GD-13A Commercial/Industrial Rotary Meter Set Assembly 2,000-3,000 SCFH
GD-13B Commercial/Industrial Rotary Meter Set Assembly 2,000-3,000 SCFH
GD-14A Commercial/Industrial Rotary Meter Set Assembly 5,000 & 7,000 SCFH
GD-14B Commercial/Industrial Rotary Meter Set Assembly 5,000 & 7,000 SCFH
GD-14C Commercial/Industrial Rotary Meter Set Assembly 5,000 & 7,000 SCFH
GD-15A Commercial/Industrial Rotary Meter Set Assembly 5,000-7,000 SCFH
GD-15B Commercial/Industrial Rotary Meter Set Assembly 5,000-7,000 SCFH
GD-15C Commercial/Industrial Rotary Meter Set Assembly 5,000-7,000 SCFH
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TABLE OF CONTENTS Appendix C Gas Details
CITY OF PALO ALTO PAGE 2
GD-16A Commercial/Industrial Rotary Meter Set Assembly 11,000 SCFH
GD-16B Commercial/Industrial Rotary Meter Set Assembly 11,000 SCFH
GD-17A Commercial/Industrial Rotary Meter Set Assembly 11,000/16,000 SCFH
GD-17B Commercial/Industrial Rotary Meter Set Assembly 11,000/16,000 SCFH
GD-17C Commercial/Industrial Rotary Meter Set Assembly 11,000/16,000 SCFH
GD-18A Industrial Rotary Meter Set Assembly 23,000 SCFH
GD-18B Industrial Rotary Meter Set Assembly 23,000 SCFH
GD-18C Industrial Rotary Meter Set Assembly 23,000 SCFH
GD-19A Industrial Ultrasonic Meter Set Assembly 16,000-25,000 SCFH
GD-19B Industrial Ultrasonic Meter Set Assembly 16,000-25,000 SCFH
GD-19C Industrial Ultrasonic Meter Set Assembly 16,000-25,000 SCFH
GD-19D Industrial Ultrasonic Meter Set Assembly 16,000-25,000 SCFH
GD-20A Industrial Ultrasonic Meter Set Assembly 23,000-45,000 SCFH
GD-20B Industrial Ultrasonic Meter Set Assembly 23,000-45,000 SCFH
GD-20C Industrial Ultrasonic Meter Set Assembly 23,000-45,000 SCFH
GD-20D Industrial Ultrasonic Meter Set Assembly 23,000-45,000 SCFH
GD-20E Industrial Ultrasonic Meter Set Assembly 23,000-45,000 SCFH
GD-21 Curb Gas Meter 250-630 SCFH
GD-22 Multiple Curb Gas Meters 250-630 SCFH
GD-23A Utility Box (Curb Location) Meter Set Assembly 250 SCFH
GD-23B Utility Box (Curb Location) Meter Set Assembly 250 SCFH
GD-23C Utility Box (Curb Location) Meter Set Assembly 400-630 SCFH
GD-23D Utility Box (Curb Location) Meter Set Assembly 400-630 SCFH
GD-24A Commercial Curb Gas Rotary Meter 800-2,000 SCFH Utility Box (Curb Location)
GD-24B Commercial Rotary Meter Set Assembly 800-1,100 Utility Box (Curb Location)
GD-24C Commercial Rotary Meter Set Assembly 800-1,100 Utility Box (Curb Location)
GD-25A Commercial Rotary Meter Set Assembly 1,500-2,000 SCFH Utility Box (Curb Location)
GD-25B Commercial Rotary Meter Set Assembly 1,500-2,000 SCFH Utility Box (Curb Location)
GD-25C Commercial Rotary Meter Set Assembly 1,500-2,000 SCFH Utility Box (Curb Location)
GD-26A Commercial/Industrial Curb Gas Rotary Meter 2,000-3,000 SCFH Utility Box (Curb)
GD-26B Commercial/Industrial Rotary Meter Set Assembly 2,000-3,000 SCFH Utility Box (Curb)
GD-26C Commercial/Industrial Rotary Meter Set Assembly 2,000-3,000 SCFH Utility Box (Curb)
GD-26D Commercial/Industrial Rotary Meter Set Assembly 2,000-3,000 SCFH Utility Box (Curb)
GD-27A Commercial/Industrial Curb Gas Rotary Meter 5,000-7,000 SCFH Utility Box (Curb)
GD-27B Commercial/Industrial Rotary Meter Set Assembly 5,000-7,000 SCFH Utility Box (Curb)
GD-27C Commercial/Industrial Rotary Meter Set Assembly 5,000-7,000 SCFH Utility Box (Curb)
GD-27D Commercial/Industrial Rotary Meter Set Assembly 5,000-7,000 SCFH Utility Box (Curb)
GD-28A Gas Service Regulator Vent Extension Assembly
GD-28B Gas Service Regulator Vent Extension Assembly
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TABLE OF CONTENTS Appendix D Wastewater Details
CITY OF PALO ALTO PAGE 1
Table of Contents
Appendix D
Wastewater Standard Details
Detail No. Title
WWD-01A Sanitary Sewer Lateral
WWD-01B Sanitary Sewer Lateral with Backwater Valve Protection Type 1
WWD-01C Sanitary Sewer Lateral with Backwater Valve Protection Type 2
WWD-02A Sanitary Sewer Cleanout Type 1
WWD-02B Sanitary Sewer Cleanout Type 2
WWD-03 Sanitary Sewer Cleanout Box Type 1
WWD-04 Sanitary Sewer Cleanout Box Type 2 (Traffic Area)
WWD-05 Sanitary Sewer Lateral - Main Connections
WWD-06 Sanitary Sewer Lateral Connection with Tap-Tite
WWD-07A Sanitary Sewer Manhole (For New Pipes 36” and Less)
WWD-07B Sanitary Sewer Manhole (For Existing Pipes 36” and less)
WWD-08A Sanitary Sewer Manhole (For New Pipes Larger Than 36”)
WWD-08B Sanitary Sewer Manhole (For Existing Pipes Larger Than 36”)
WWD-09 Sanitary Sewer Manhole Outside Drop
WWD-10 Sanitary Sewer Manhole Frame and Cover
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Water Gas & Wastewater
Utility Standards
2024
Utilities Department
INTRODUCTION SECTION 01
CITY OF PALO ALTO Section 01 PAGE 1
SECTION 01
INTRODUCTION
1.01 INTRODUCTION
The 2023 WGW Utility Standards shall govern the requirements for design and construction of all water, gas,
and wastewater utilities within the City of Palo Alto’s public right-of-way. All drawings and specifications for
City projects or private development projects within the public right-of-way shall conform to 2023 WGW Utility
Standards, unless otherwise approved by the WGW Engineering Manager. Private utilities on private
properties fall under the jurisdiction of the City’s Planning Department, Building Inspection Division. A new
edition of the WGW Utility Standards is anticipated to be issued annually. The electronic downloadable file is
available at City of Palo Alto Utilities Engineering website:
https://www.cityofpaloalto.org/files/assets/public/utilities/utilities-engineering/general-specifications/2024-
wgw-utility-standards_online-version.pdf
Dean Batchelor Matt Zucca, P.E.
Director Assistant Director
Utilities Department Utilities WGW Engineering and Operations
Silvia Lee Santos, P.E. Aaron Perkins, P.E.
Engineering Manager Principal Engineer
Utilities Engineering/WGW Utilities Engineering/WGW
Tuan Nguyen, P.E. Nelson Schlater, P.E.
Principal Engineer Principal Engineer
Utilities Engineering/WGW Utilities Engineering/WGW
Patrick LaBruzzo, P.E. Jose Jovel
Principal Engineer Utilities Supervisor
Utilities Engineering/WGW Utilities Engineering
END OF SECTION
TABLE OF CONTENTS WGW UTILITY STANDARDS
CITY OF PALO ALTO PAGE 1
Table of Contents
WGW Utility Standards
Technical Specifications
Section No. Title
Section 800 Additional Provisions for Utilities Contractors
Section 860 Street Pavement Schedule – Example
Section 870 Policy and Procedures for Water Use
Section 1500 Site and Traffic Control for WGW Utilities Contractors
Section 2200 Excavation, Backfill, and Restoration
Section 2300 Polyethylene Pipe Installation for WGW
Section 2400 Fusion Procedures and Certification for Water and Sewer
Section 2500 Fusion Procedures and Certification for Gas
Section 2660 Water Design and Construction Standards
Section 2685 Natural Gas Distribution System
Section 2730 Wastewater Design and Construction Standards
Section 2731 Vitrified Clay Sewer Pipe
Section 2733 Polyvinyl Chloride Sewer Pipe
Section 2735 Sewer Construction with Polyethylene Pipe
Section 2735-1 Form for Open Trench Contractor/Subcontractor Experience
Section 2735-2 Form for Open Trench Superintendent/Foreman Experience
Section 2735-3 Form for Pipe-Bursting Contractor/Subcontractor Experience
Section 2735-4 Form for Pipe-Bursting Superintendent/Foreman Experience
Section 2736 Cured-in-Place Pipe (CIPP)
Section 2736-1 Form for CIPP Contractor/Subcontractor Experience
Section 2736-2 Form for CIPP Superintendent/Foreman Experience
Section 2737 Sanitary Sewer Lateral
Section 2738 Concrete Manholes
Section 2739 Cleaning and Video Inspection of Sewer Pipe
Section 2740 Survey Data Collection
Section 2741 Legacy Cross Bore Inspection Guidelines
Appendices
Appendix A General WGW Utility Standard Details
Appendix B Water Standard Details
Appendix C Gas Standard Details
Appendix D Wastewater Standard Details
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 1
SECTION 800
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS
PART 1 – GENERAL
1.01 DESCRIPTION
The additional provisions in this section apply to work on Utilities Capital Improvement Projects
(CIP).
1.02 DEFINITIONS
Capitalized terms which are not otherwise defined in these Standards have the same meaning
provided in Article 1 of the City’s General Conditions.
1.03 COST SAVINGS INCENTIVE
The Contractor may suggest contract cost savings changes by means of a contract cost savings
proposal (CCSP). If these changes are approved by the City as deductive change orders, the
contract cost savings shall be shared by the Contractor and City, as long as the proposed change
is of equal or greater performance that meets the original design’s performance goal(s). The
sharing of cost savings shall be 50 percent to the Contractor and 50 percent to the City. The City's
cost for reviewing the Contractor's suggested savings shall include the cost of engineering services
for evaluation of proposals and cost of required redesign. The City's total cost for all reviews of
Contractor proposals shall be deducted from the total cost savings to be shared.
The Contractor may suggest savings at any time during the contract period. The Engineer will
evaluate Contractor-suggested cost savings and the City will make a decision as to whether or not
to make the change.
At a minimum, the Contractor shall include in each CCSP the following information:
A. A description of the difference between the existing contract requirement and the proposed
change. The comparative advantages and disadvantages of each, a justification of the
alteration of an item's function or characteristics, and the effect of the change on the item's
performance.
B. A list and analysis of the contract requirements that must be changed if the CCSP is
accepted, including any suggested revisions to the project specifications.
C. A separate, detailed cost estimate for (a) the affected portions of the existing contract
requirement and (b) the CCSP shall be submitted. The cost reduction associated with the
CCSP, shall take into account the Contractor's development and implementation costs as set
forth in the City Standard Drawings and Specifications, including any amount attributable to
subcontracts.
D. A statement of the time by which a contract modification accepting the CCSP must be issued
in order to achieve the maximum cost reduction, noting any effect on the contract completion
time or delivery schedule.
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 2
The Engineer will process CCSP's expeditiously, however, in no case will a deductive change order,
proposed during the time period or later in the project, be the basis of a time extension.
If the CCSP is not accepted, the Engineer will notify the Contractor in writing, explaining the reasons
for rejection. The Contractor may withdraw any CCSP, in whole or in part, at any time before it is
acted upon by the Engineer.
1.04 TYPICAL TIMELINE AND CONTRACTOR REQUIREMENTS FOR NOTICE OF AWARD,
CONTRACT EXECUTION, NOTICE TO PROCEED, PRE-CONSTRUCTION SUBMITTALS, PRE-
CONSTRUCTION CONFERENCE, AND COMMENCEMENT OF WORK
The typical or anticipated times provided for City actions in this section are provided solely for the
Contractor’s convenience, and will not be binding against the City since the actual time for the City’s
action may vary depending on applicable circumstances.
A. The Notice of Award typically is issued within ten (10) business days of the City-Council
approval date.
B. Per IFB Part 2 Instructions to Bidders Section 9.3, the Contractor must submit all required
documentation, including, without limitation, all bonds and evidence of insurance within ten (10)
business days of the date of issuance of the Notice of Award.
C. The Notice to Proceed is anticipated to be issued within twenty (20) business days from the
Notice of Award and when the Contract is fully executed. The Notice to Proceed may specify
the pre-construction submittal due date, pre-construction conference date, and the anticipated
project commencement date.
D. The Contractor must submit all pre-construction submittals, as specified in the Contract
Documents or listed in the Construction Submittal List in IFB Appendices, for City’s
approval within ten (10) business days from the Notice to Proceed issuance date.
E. The pre-construction conference is anticipated to be scheduled for 20 days after the pre-
construction submittal deadline.
F. The commencement of work date is anticipated to be 10 days after the pre-construction
conference, when pre-construction submittals are substantially or completely approved.
commencement
1.05 SUBMITTALS
In addition to complying with the general submittal requirements in Section 3.12 of the General
Conditions, Contractor must meet any specified project milestones by submitting required pre-
construction submittals in advance to avoid delays due to submittal review or material lead time.
As further specified in Section 6.4 of the Construction Contract, liquidated damages may be
assessed if the Contractor fails to meet specified project milestones. All pre-construction submittals
must be approved prior to delivery of the material/equipment to the job site that the submittal relates
to or starting the portion of work. Unless specifically stated elsewhere in the Contract
Specifications, the Contractor shall make submittals in advance of ordering the materials to provide
sufficient time for review, approval, possible revisions and re-submittals, and placing
orders/securing delivery. For Utilities contracts, the Notice to Proceed will be issued when all
submittals are approved.
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 3
Ultimate responsibility for the accuracy and completeness of the information contained in each
submittal shall remain with the Contractor. Unless otherwise specified, make submittals in groups
containing all associated items to assure that required information is available for checking when
the submittal is received. Partial submittals may be rejected as not complying with the provisions
of the Contract and the Contractor may be held liable for delays so occasioned. The Engineer will
supply a checklist of items that shall be submitted by the Contractor for approval.
If the submittal is returned to the Contractor marked "NO EXCEPTIONS TAKEN", or "MAKE
CORRECTIONS NOTED", or “RECEIPTeceipt ACKNOWLEDGEDcknowledged”, formal revision
and resubmission of the submittal will not be required. Fabrication of any item shall not commence
before the Engineer has reviewed the pertinent submittals and returned copies to the Contractor
marked "NO EXCEPTIONS TAKEN" or “MAKE CORRECTIONS NOTED.”
If the submittal is returned to the Contractor marked "REVISE AND RESUBMIT" or "REJECTED",
the Contractor shall, within five (5) business days, make a complete and acceptable submittal to
the Engineer by the second submission of a submittal item. When material is resubmitted for any
reason, transmit under a new letter of transmittal and with a new transmittal number; on re-
submittals, cite the original submittal number for reference.
Revisions indicated on submittals shall be considered as changes necessary to meet the
requirements of the contract and shall not be taken as the basis of claims for extra work. If the
Contractor considers any required revision to be a change, he shall so notify the Engineer as
provided for in the General Conditions.
The Contractor shall maintain an accurate submittal log for the duration of the Work, showing
current status of all submittals at all times, and keep it available to the Engineer for his review upon
request.
Where contents of submitted literature from manufacturers include data not pertinent to the
submittal, clearly show which portions of the contents are being submitted for review.
The Engineer's review of the Contractor's submittals shall not relieve the Contractor of the entire
responsibility for the correctness of details and dimensions. The Contractor shall assume all
responsibility and risk for any work not conforming to the contract. Any fabrication or other work
performed in advance of the receipt of approved submittals shall be entirely at the Contractor's risk
and expense.
1.06 MEETINGS
A. Pre-Construction Conference/Meeting
The Contractor must submit all construction submittals, as specified in the Contract
Documents, for City approval within 20 business days from Notice of Award is issued. Upon
City approval of Contractor’s construction submittals, City may will conduct a mandatory pre-
construction meeting when pre-construction submittals are substantially or completely
approved, typically schedule a mandatory pre-construction meeting 20 business days after
the pre-construction submittal due date. The pre-construction submittal due date is 10
business days from the Notice to Proceed issuance date per Section 1.04.D. The C
Contractor’s primary representative and its Superintendent for the project must attend the
meeting, which will include discussion of the scope of work, sequence of operations, project
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 4
milestones if appropriate, and project requirements. The Contractor may include other
supervisory personnel and representatives from key subcontractors as well.
Work on the project cannot commence until all required pre-construction submittals
have been approved by the City. Contractor will be solely responsible for delay in
authorizing commencement of the work by the plannedfailing to meet project start date,
milestones, and/or any delay in project completioncompletion date resulting from delay in
project commencement due to Contractor’s failure to provide all pre-construction submittals as
specified.
B. Project Meetings
Following commencement of the work, Contractor’s Superintendent must attend and
participate in regular weekly project meetings as scheduled by the Engineer. The
Subcontractor and supplier representatives may only attend the regular project meetings when
specifically invited by the Engineer.
The meetings will be conducted by the Engineer, and the Engineer will keep minutes of the
proceedings.
The Engineer will establish the agenda for each project meeting, which may include matters
including, but not limited to, reports on construction progress, the status of submittal reviews,
the status of record drawings, progress payment requests, the status of information requests,
and any general business.
1.076 SCHEDULE UPDATE
A. In addition to the monthly schedule requirements in Section 3.10.3 of the General Conditions,
one day prior to each weekly project meeting, Contractor must submit to Engineer an updated
and detailed rolling 3-week look-ahead schedule, that is tied to the overall construction
schedule.
It is imperative that the schedule be kept up to date. At any time during the progress of the
work, the Engineer may request an updated or revised construction schedule if there is
evidence that progress is lagging by a week or more from the last submitted schedule. The
Contractor shall provide such updated or revised schedule within two (2) Working Days.
B. It is the Contractor's responsibility to keep the Engineer continually informed as to the location
and timing of all the work. Prior to starting each day’s work, the Contractor shall email the
planned work for the day, including road or lane closures, to the Inspector and Engineer.
1.08 NOTIFICATION
The Contractor shall provide written notification of the work to abutting property owners at least
fifteen (15) Days and again 24 hours prior to commencing work at their specific locations. If the
driveway to any garage or parking area is to be closed for work, the notice shall state the
approximate time of work in the driveway and when the work area will be reopened. No overnight
closure of any driveway will be permitted.
1.09 ON-SITE SUPERVISION
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 5
A contractor’s superintendent or foreman, or designated superintendent or foreman, is required to
be physically on-site the entire day for the duration of the Work to supervise all construction
activities. Substitution of superintendents or foremen shall be approved by the Engineer.
Any superintendent/foreman expected to perform polyethylene pipe fusion shall be tested and
qualified in accordance with Section 2300 Polyethylene Pipe Installation (2.02.H.2).
1.10 PROGRESS PAYMENT
In addition to the provisions of Article 9 of the General Conditions, including Section 9.2 on progress
payments, Applications for Payment for Utilities Capital Improvement Program (CIP) projects must
also list the locations where the work was performed, including names of streets with reference to
the Project drawings and corresponding station numbers. All addresses of service lines, installed
or reconnected, and locations of other invoiced items must be also included in the invoice.
The Application for Payment must include all of the following:
A. GPS survey data collected and furnished in accordance with requirements stated in Section
2740 of these specifications for infrastructure installed within the pay period stated on the
invoice. The Contractor shall submit the GPS data set collected for the installation work during
the first week of construction and subsequently every month, with or without an invoice, for the
City to validate its accuracy.
B. The completeness and accuracy of GPS survey data shall be verified by the City before the
issuance of each payment to the contractor. If the GPS survey data is found incomplete or
inaccurate, the City may require the Contractor, at Contractor’s own expense, to reopen or
uncover GPS surveyed infrastructure/objects and perform new survey if the accuracy of the
originally submitted data is not in compliance with these specifications. The Contractor will be
required to perform surface restoration, at the Contractor’s own expense, following the
additional survey.
C. Submission of checklists of all notified affected property owners (15 day and 24-hour notices).
D. Submission of data logger and electrofusion records.
E. Video on USB flash drive, hard drive, or provided through a Cloud platform of post construction
sewer main and/or lateral video as specified in these Specifications for pay period stated on
the invoice (if applicable).
F. List of quantities verified by City Inspection.
F.G. Updated construction schedule as specified in Section 3.10 of the General Conditions.
G.H. Additional items (special requirements) as stated below:
1. Water CIP Projects:
a. A successful hydrostatic pressure/leak and bacteriological test, as specified in Section
2660 of these specifications, of the water system installed in the pay period stated on
the invoice.
2. Gas CIP Projects:
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 6
a. A successful pressure test of the gas system installed in the pay period stated on the
invoice.
b. Submission of an attached CIP Gas Main Replacement Project Polyethylene Gas Pipe
Fusion Records Form and automated fusion machine data printouts.
b.c. Records of bore logs.
c.d. Pre and Ppost construction sewer lateral/main cross bore verification completed,
submitted, and accepted in accordance with the procedures stated in Sections 2739
and 2741 of these specifications.
d. Full completion of surface restoration on private property affected by the construction
in the stated pay period, including but not limited to, installation of bollards and surface
restoration around risers.
3. Wastewater CIP Projects:
a. All sewer main/lateral post-construction CCTV inspection per Section 2739.
PART 2 – QUALITY CONTROL
2.01 DESCRIPTION
A. Work Included:
1. Qualifications of workmen
2. Codes and Standards
3. Testing
4. Equipment and materials
5. Inspection and approval of work
6. Manufacturers' recommendations
B. Related Work: Requirements for testing are described in various Sections of the Contract
Specifications.
2.02 QUALIFICATIONS OF CONTRACTOR PERSONNEL
Provide workers in sufficient number who are thoroughly trained and experienced in the skills
required. They shall be completely familiar with the work requirements and construction methods
to complete the work described for each respective Section. A supervisor and competent person
shall be present at all times during progress of the work of each respective Section and shall direct
all work performed under each respective Section.
Contractor personnel performing polyethylene pipe fusion must produce documentation from a pipe
supplier stating their qualification to perform said work and shall be tested by the City for certification
to fuse on City piping per Section 2300 of these specifications. See Sections 2400 and 2500 for
fusion procedures and certification on water, gas, and wastewater facilities.
Workers performing work on natural gas facility shall be tested by the City for the certification per
Section 2685.3.07 Operator Qualification Requirements.
Contractor personnel performing directional drilling operations on State of California property,
involving a State of California permit, or falling under the authority of the State of California (Caltrans
Right-Of-Way) must provide proof-of-training certification acceptable to Caltrans.
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 7
Contractor personnel performing pipe-bursting work shall comply to Section 2735 for qualification
requirements.
Contractor personnel performing work within Caltrain Property are required to have successfully
completed, within the last twelve (12) months, Caltrain’s Roadway Worker Protection training
program. The Contractor shall forward to Caltrain records of those who successfully completed
the course. The Contractor shall, at all time, comply with provisions of the Federal Rail
Administration Regulation 49CFR214 (Roadway Worker Protection), the Caltrain/Amtrak Zero
Tolerance Policy, and the Permittor (Licensor) On-Track Safety Program.
2.03 CODES AND STANDARDS
The following reference standards (latest version) in addition to the Project Plans and
Specifications are hereby incorporated by reference and shall be referred to in this specification
by their abbreviations. These reference standards shall apply to all applicable work of this contract.
A. PUBLIC WORKS STANDARD DRAWINGS AND SPECIFICATIONS: The latest edition of City of
Palo Alto Public Works Standard Drawings and Specifications (The electronic downloadable file is
available at https://www.cityofpaloalto.org/Departments/Public-Works/Engineering-Services/Public-Works-
Standard-Drawings-and-Specifications).
B. WATER, GAS, AND WASTEWATER UTILITY STANDARDS: The latest edition of City of Palo
Alto Water, Gas, and Wastewater Utility Standards (The electronic downloadable file is available
at https://www.cityofpaloalto.org/Departments/Utilities/Utilities-Services-Safety/Engineering-and-
Operations).
C. CITY OF PALO ALTO TRAFFIC CONTROL MANUAL: The latest edition of the Traffic Control
Requirements is available at https://www.cityofpaloalto.org/files/assets/public/public-works/engineering-
services/webpages/forms-and-permits/other-guidelines/requirements-for-traffic-control-plan-submission-
2021.pdf.
D. MANUAL ON UNIFORM TRAFFIC CONTROL DEVICES (MUTCD) – CALTRANS
E. WORK AREA TRAFFIC CONTROL HANDBOOK (WATCH BOOK)
BNI Publications Inc.
F. Tree Technical Manual
Department of Planning and Community Environment, latest edition
G. U.S. DEPARTMENT OF TRANSPORTATION, PIPELINE SAFETY REGULATIONS, PARTS 190
TO 199. Copies of these regulations are available for purchase from the following address:
Transportation Safety Institute
Pipeline Safety Division DMA-607
6500 S. MacArthur Blvd.
Oklahoma City, OK 73125
H. OSHA Consultation and Compliance Section
U.S. Department Of Labor
Occupational Safety and Health Administration
71 Stevenson St. Suite 415
San Francisco, California 94105
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 8
I. CAL-OSHA
Department of Industrial Relations
State of California
Occupational Safety and Health Administrations
525 Golden Gate Ave.
San Francisco, CA 94102
J. UPC
Uniform Plumbing Code
20001 Walnut Drive South
Walnut, CA 91789-2825
K. UBC
Uniform Building Code
5360 South Workman Mill Road
Whittier, CA 90601
L. NEC
National Electric Code
National Fire Protection Association
Batterymarch Park
Quincy, MA 02269
M. UFC
Uniform Fire Code
5360 South Workman Mill Road
Whittier, CA 90601
N. UL
Underwriters Laboratories
1655 Scott Boulevard
Santa Clara, CA 95050
O. AWWA
American Water Works Association
6666 West Quincy Avenue
Denver, CO 80235-3098
P. NSF
National Sanitary Foundation
789 Dixboro Road
Ann Arbor, MI 48113-0140
2.04 TESTING
A. Code Compliance Testing: Inspections and tests required by codes or ordinances, or by a plan
approval authority, and which are made by a legally constituted authority, shall be the
responsibility of and shall be paid for by the Contractor, unless otherwise provided in the
Contract Documents.
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 9
B. Contractor's Convenience Testing: Inspection and testing performed exclusively for the
Contractor’s convenience shall be the sole responsibility of the Contractor.
C. Provide "Certificates of Compliance" when required and other testing and inspecting as are
specified to be furnished by the Contractor in this Section and/or elsewhere in the Contract
Documents.
D. Testing, when required, will be in accordance with the selected standards of the American
Society for Testing and Materials (ASTM).
E. The testing laboratory will be qualified subject to the CITY's approval.
PART 3 - PRODUCTS
3.01 EQUIPMENT AND MATERIALS
All equipment and materials furnished shall be new and the best of their respective kinds, free from
all defects and as specified in the Drawings and Specifications or as approved and accepted in
writing by the Engineer.
All equipment, materials, and devices shall be installed in accordance with the recommendations
of the manufacturer, unless otherwise approved by the Engineer. Prior to the start of work, the
Contractor shall obtain and deliver copies to the Engineer of all installation manuals, brochures,
and procedures that the manufacturer issues for the items supplied.
For projects with specific start or completion dates, it is the Contractor’s responsibility to include
necessary costs to expediate the delivery of any long-lead items to avoid delays and comply with
project specifications.
3.02 EXCESS MATERIALS
The Contractor shall return all salvageable fire hydrants and meter box lids to the City’s Municipal
Service Center. Any excess materials shall be returned to their appropriate suppliers. At no time
shall excess materials be dropped off at the City’s Municipal Service Center. All transportation and
re-stocking fees (invoice required) will be paid to the Contractor only if the City authorized the work
to be canceled. The Contractor will not be paid for excess materials that are over-ordered and/or
purchased without approved submittals.
PART 4 - EXECUTION
4.01 APPROVAL OF WORK
All work to be performed and all material to be furnished by the Contractor shall be subject to
inspection by the Engineer at all any times and shall be performed and furnished to their
satisfaction. Any work concealed before it has been inspected by the Engineer or their
representative shall, at the request of the Engineer, be reopened or uncovered. If deficiencies are
found, these deficiencies shall be corrected at the Contractor’s expense.
The City reserves the right to inspect materials or equipment during the production, manufacturing
or fabricating process, or before shipment.
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 10
Neither acceptance of the Work, nor final payment, shall relieve the Contractor of the responsibility
for performing the Work in accordance with the Contract requirements. The Contractor shall
remedy any work not conforming to the Contract without expense to the City.
4.02 MANUFACTURER'S RECOMMENDATIONS
Whether specifically mentioned or not in the Drawings or Specifications, all equipment, materials,
devices, etc., shall be installed in a manner meeting the manufacturer's recommendations for the
particular item. Prior to the start of work, the Contractor shall obtain and deliver copies to the
Engineer of all installation manuals, brochures, and procedures that the manufacturer issues for
the items supplied. The Contractor shall be held responsible for all installation contrary to the
manufacturer's recommendations, unless otherwise approved by the Engineer. If any item or piece
of equipment or material is found to be installed not in accordance with the manufacturer's
recommendations, or as otherwise directed by the Engineer, the Contractor shall make all
necessary changes and revisions to achieve such compliance at the Contractor's expense.
4.03 COOPERATION WITH TESTING LABORATORY
A. Representatives of the testing laboratory shall have access to the Work at all times and all
locations where the Work is in progress. Contractor shall provide such access to enable the
laboratory to perform its functions properly.
B. Cooperate with the City's selected testing agency and all others responsible for testing and
inspecting the Work.
4.04 TAKING SPECIMENS
All specimens and samples for testing, unless otherwise provided in the Contract Documents, shall
be taken by the testing personnel. All sampling equipment and personnel will be provided by the
testing laboratory. All deliveries of specimens and samples to the testing laboratory will be
performed by the testing laboratory.
4.05 PRODUCT HANDLING
Contractor shall promptly process and distribute required copies of test reports and related
instructions for the "Certificate of Compliance" to allow necessary retesting and/or replacement of
materials with the least possible delay in progress of the Work.
4.06 SCHEDULES FOR TESTING
A. Establishing Schedule:
1. By advance discussion with the testing laboratory selected by the City, determine the time
required for the laboratory to perform its tests and to issue each of its findings.
2. Provide no less than 48-hour notice to the Engineer when testing will be required and
provide all required time within the construction schedule to perform necessary testing.
B. Revising schedule: When changes of construction schedule are necessary during construction,
Contractor shall coordinate all such changes with the testing laboratory as required.
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 11
C. Adherence to Schedule: If the testing laboratory is prevented from testing or taking specimens
due to incompleteness of the Work, all extra charges for testing attributable to the delay will be
back-charged to the Contractor and shall not be borne by the City.
4.07 PAYMENT FOR TESTING
Contractor shall pay for all testing (excluding soil compaction testing) and re-testing required to
comply with the Contract Specifications, Codes, Regulations, and all other applicable laws.
Contractor is responsible to pay for the soil compaction testing technician’s waiting time if the trench
backfill is not ready to be tested at the scheduled time. Contractor shall also pay for the soil
compaction testing technician’s time to re-test if the test fails. Progress payments will be deducted
for the hours the City is billed due to Contractor’s delay.
4.08 DAMAGE TO PUBLIC OR PRIVATE PROPERTY
Damage to public or private property shall be repaired in kind or as the Engineer shall direct, at the
Contractor's expense. This includes, but not limited to the repair or replacement of streets,
sidewalks, underground utilities, City monuments, traffic facilities, traffic loop detectors, striping,
legends, signals, signs, pavement markers, trees, and landscaped areas. Temporary traffic
markers shall be placed immediately after final paving to properly channel traffic.
If damage to utilities occurs beyond the City’s Right-of-Way, the Contractor shall coordinate with
the City’s Building Division to acquire permits and schedule on-site inspection. The Contractor is
responsible for all costs associated with the repair, inspection, and permits for the restoration of
on-site plumbing. Visit https://www.cityofpaloalto.org/gov/depts/ds/default.asp to acquire permits
or schedule inspection.
4.09 WORK OUTSIDE OF PUBLIC RIGHT OF WAY
Project specified work that is outside the public right-of-way shall be conducted with care and
consideration consistent with the requirements of these Specifications, Public Works Standard
Drawings and Specifications, and/or Building Code including other referenced standards of this
specification. The Contractor is prohibited from advertising its services to the owners/residents of
properties and businesses affected by the project construction for the duration of the Contract.
For work on private property, it is the Contractor’s responsibility to contact the owner or occupant
to coordinate the schedule and access. Sufficient notification shall be provided by the Contractor
to the owner or occupant to avoid delays.
4.10 MONUMENT REPLACEMENT
All monuments within the project site shall be preserved as required by the State and local
regulations. Damaged or destroyed monuments shall be replaced by a California licensed Land
Surveyor hired by the Contractor. The Contractor shall submit the method and procedures of tying
out the monuments for the City Surveyor’s approval. The Contractor shall also provide a recorded
copy of the “corner record” to the City Surveyor. No separate bid item was made for the cost of any
surveying or monument replacement work. The cost shall be included in one or more of the bid
items.
4.11 METERED OR PERMIT-REQUIRED PARKING
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 12
The Contractor is responsible for obtaining and paying (not compensated by the City) for all
metered parking or permit-required parking spaces occupied by contractor’s personal vehicles
inside or outside of the immediate construction zones. The contractor is also responsible to pay for
any metered parking or permit-required parking spaces made unavailable by construction
equipment, vehicles, or material during non-working hours or outside the immediate construction
zone(s).
ADDITIONAL PROVISIONS FOR UTILITIES CONTRACTORS SECTION 800
CITY OF PALO ALTO Section 800 PAGE 13
4.12 Photos/Video of Existing Site Condition
The Contractor shall take photos and video of existing jobsite conditions and temporary storage
areas prior to the commencement of work. The Contractor shall be responsible for site restoration
to pre-construction conditions if the damage is caused by the Contractor’s work or storage. If the
Contractor fails to document existing condition of public or private properties prior to construction,
the Contractor will be held liable for any damage sustained at the construction sites or storage
areas.
4.13 Reporting Requirements of Sanitary Sewer Overflows (SSOs)
The following policy shall apply:
x In the event of a SSO that is observed or created by the Contractor, the Contractor will immediately notify the City’s Dispatch by calling 650-329-2413 and the assigned City
Inspector. x The following information should be reported to the City’s Dispatch: location of the SSO, contact information of the Contractor representative and City Inspector, time Contractor first
noticed the SSO, and if SSO is occurring at the time of the call. x Utility Dispatch may contact Wastewater Operations to respond. x The Contractor must take appropriate steps to stop, contain, or divert the SSO by using
absorbent, portable dams, sandbags, or by-pass equipment. x The responding Operations’ crew may assist the Contractor with stopping, containment, or diversion of SSOs and complete field reports associated with the SSO.
END OF SECTION
STREET PAVEMENT SCHEDULE - EXAMPLE SECTION 860
CITY OF PALO ALTO Section 860 PAGE 1
SECTION 860
STREET PAVEMENT SCHEDULE
Surface restoration shall include all materials and labor required to restore the area both below and above
ground. Restoration of pavement sections, sidewalks, driveways, landscaping, curbs and gutters, and backfill
shall conform the City Standard Drawings and Specifications, latest version adopted. The pavement restoration
shall be as per City’s restoration requirements and in accordance with the Public Works Department Standard Drawings
and Specifications and Project Drawings.
Existing Pavement Section Table (Example)
Legend for Surface Type:
AB2 – Aggregate Base (Class 2)
AC – Asphalt Concrete
CRB – Crusher Run Base DLAC – Deep Lift Asphalt Concrete PCC – Portland Cement Concrete
The pavement thickness type information provided above may not represent 100% of the actual pavement
thickness in the project areas. For bidding purposes, the Contractor shall assume the minimum required
thickness from the CPA Standard Specifications if the information is not available. For bidding purposes, the
Contractor shall assume additional pavement thickness of up to 25% from the data provided and the CPA
Standard Specifications, whichever is greater.
For restoration within other agencies’ right-of-way, the Contractor shall contact and follow the direction and
requirements of the permitting agency.
The cost of pavement restoration shall be included in one or more of the bid items. If the discrepancy occurs
between the proposed section and the actual pavement thickness, the Engineer shall be informed to verify the
existing pavement thickness. The pavement shall be restored “in-kind” meeting the minimum requirement per
CPA Standard Specifications.
SHEET
NUMBER STREET BETWEEN AND SURFACE
TYPE
SURFACE
THICKNESS
(INCH)
BASE
TYPE
BASE
THICKNESS
(INCH)
Pavement
Condition
5,6 Geng Rd Embarcadero Rd End of Geng Rd AC 3 AB2 12 Poor
7,8,9 Arboretum Rd Sand Hill Rd Orchard Ln AC 1 CRB 10 Fair/At-Risk
12 University Ave Webster St Byron St AC 4 DLAC 8 Very
Good/Excellent
STREET PAVEMENT SCHEDULE - EXAMPLE SECTION 860
CITY OF PALO ALTO Section 860 PAGE 2
END OF SECTION
POLICY AND PROCEDURES FOR WATER USE SECTION 870
CITY OF PALO ALTO Section 870 PAGE 1
SECTION 870
POLICY AND PROCEDURES FOR WATER USE
PART 1 - GENERAL
1.01 GENERAL
Reclaimed water shall be used for backfill compaction, and cleaning and testing of manholes. An
overhead standpipe with a five hundred (500) gallon per minute (gpm) fill rate is available at the Palo
Alto Regional Water Quality Control Plant (RWQCP) between Monday through Friday, 6:30 a.m. to
5:00 p.m., except on public holidays. A recycled hydrant is also available for 24-hours a day, 7-days a
week to active permit holders and is located at Greer Park, near 1198 Colorado Avenue, Palo Alto,
CA. This will allow self-service pickup and use of reclaimed water on a first come-first serve basis, up
to the capacity of the reclamation plant of four and a half (4.5) million gallons per day (MGD).
The permit may be obtained on the City’s website at:
https://www.cityofpaloalto.org/files/assets/public/public-works/water-quality-control-plant/recycled-
water/2021/9.-user-guidelines-and-application.pdf and shall be submitted to the RWQCP at 2501
Embarcadero Way, Palo Alto, CA with a $50 check or money order payable to the “City of Palo
Alto”. For additional information, call 650.329.2598 or e-mail recycledwater@cityofpaloalto.org
City Contractors are required to provide their company’s Certificate of Liability Insurance as part of
the requirements for applying for a permit to claim recycled water. Applicants can request a multi-
year permit for multi-year projects for the City of Palo Alto. Permits for recycled water expire every
year end (December 31st) regardless of application date except for multiyear permits.
The City of Mountain View operates reclaimed water-filling hydrants at the end of Crittenden Lane (E.
of N. Shoreline Boulevard), and at Marine Way near Coast Avenue in Mountain View, CA. A key
deposit is required. Contact the City of Mountain View at (650) 903-6329 or at
recycledwater@mountainview.gov
Potable water for drinking, filling of water mains, etc. is available from hydrants in the vicinity of the
work. Hydrant water shall be metered with a hydrant meter obtained by contacting the City of Palo
Alto Utilities Business Office at (650) 329-2161 (Ground Floor Civic Center, 250 Hamilton Avenue,
Palo Alto). A meter deposit is required. Payment for potable water used will be deducted from the
Contractor's deposit at the time the meter is returned. Refer to the Policy and Procedures for Water
Hydrant Meter Use, for more information.
All costs and expenses for any water used on the project shall be included in one or more of the Bid
items and no extra compensation shall be paid to the Contractor for water.
PART 2 - POLICY AND PROCEDURES FOR WATER HYDRANT METER USE
2.01 USE RECLAIMED WATER WHENEVER POSSIBLE
The water consumption ordinance for the City of Palo Alto requires the review of water use for
construction purposes, to encourage the use of reclaimed water. The use of a reasonable amount of
potable water, for flushing potable water pipes, for instance, is still permissible through hydrant
meters. However, substantial water needs for construction purposes must be met with reclaimed
water.
Reclaimed water will be required for the following projects:
POLICY AND PROCEDURES FOR WATER USE SECTION 870
CITY OF PALO ALTO Section 870 PAGE 2
1. Grading projects, i.e. road construction, paving, site development, and projects reviewed by
the Water/Gas/Wastewater Division.
2. Street washing and flushing for final project clean-up.
3. Projects for which daily water use exceeds 5,000 gallons.
4. Projects for which weekly water use exceeds 25,000 gallons.
Procedures for permission to connect to City of Palo Alto hydrants and the penalties for not using the
hydrant meter properly are explained below.
Exceptions to this policy typically are granted only for very small jobs. Requests for exceptions to this
policy will be referred to the Senior Engineer in the Water/Gas/Wastewater Division for review and
determination.
2.02 HOW YOU CAN GET A HYDRANT METER
Applicants for a water hydrant use permit should come in person to the Utilities Department
Customer Service Center, 250 Hamilton Avenue, Ground Floor. At that time:
1. Complete a questionnaire about your project and its location.
2. Pay the $750 meter deposit fee.
3. Get six meter reading cards. NOTE: On or before the 25th day of each month, a card should
be completed with the current meter reading and sent to the Customer Service Center.
4. You will then be given a form to take to the Municipal Services Center (MSC) at 3201 East
Bayshore Road where you may pick up a hydrant meter. You will be assigned the meter for a
period of six (6) months. At the end of that time the meter must be returned to the MSC. If
you need potable water for the same project site after the three months, a new meter will be
issued. Included with the hydrant meter will be an instruction sheet for proper use of the
meter. By taking the meter, it is assumed that you will properly use the meter at all
times when connecting to City hydrants.
2.03 PENALTIES
By providing an applicant with hydrant meters for use of potable water at construction sites, the City
of Palo Alto is entering into a relationship of trust with the applicant. Nevertheless, City staff will, from
time to time, visit the site to ensure that the hydrant meter is being used and that it is being used
correctly. Failure to comply with any of the above rules or to properly hook up the meter according to
the instruction sheet provided with the hydrant meter, may subject the applicant to penalties.
Specifically:
A. Failure to use the hydrant meter or to use it so that water does not pass through the meter when
drawing water from a City of Palo Alto hydrant will result in fines of $50.00 per day and possible
forfeiture of all or part of the deposit, revocation of the permit, and prosecution according to the
law (Rule and Regulation 21.D.1.b.i; 21.D.1.b.iv; and 8.C.1-2).
B. Failure to submit meter-reading cards monthly and in a timely manner may result in forfeiture of
POLICY AND PROCEDURES FOR WATER USE SECTION 870
CITY OF PALO ALTO Section 870 PAGE 3
all or part of the deposit.
C. Failure to return the hydrant meter at the end of the three-month period may result in fines of
$50.00 per day and/or part of the deposit.
POLICY AND PROCEDURES FOR WATER USE SECTION 870
CITY OF PALO ALTO Section 870 PAGE 4
2.04 HYDRANT METER QUESTIONNAIRE (SAMPLE)
The following is a sample copy of the City’s Hydrant Meter Questionnaire.
HYDRANT NUMBER __________________
HYDRANT METER QUESTIONNAIRE
NAME:
BILLING ADDRESS: ___________________________________________________________
TYPE OF BUSINESS:
TYPE OF PROJECT:
PROJECT ADDRESS:
HOW WILL WATER
BE USED?
IN WHAT QUANTITY?
FOR HOW LONG?
(CIRCLE ONE)
Does your company own a truck? YES NO
Will a water truck be used on the project? YES NO
What is the capacity of the truck (in gallons)?
"SPECIAL WATER UTILITY REGULATIONS, Rule and Regulation 21, Paragraph B. 1, B. 3."
Failure to return the hydrant meter at the end of the appropriate period may result in additional
charges of $ 50.00 per day.
Have customer read this paragraph and sign for verification.
Signature Title Date
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 1
SECTION 1500
SITE AND TRAFFIC CONTROL
FOR WGW UTILITIES CONTRACTS
1.01 DESCRIPTION
Work Included in this section:
x Traffic Control
x Safety
x Sanitation Facilities
x Storage of Equipment and Materials
x Cleanup
x Signage
1.02 TRAFFIC CONTROL
A. General
All traffic control, depending on location of work and area of jurisdiction, shall be performed in strict
compliance with City of Palo Alto Transportation Division per the requirements noted herein,
CALTRANS, and/or Santa Clara County traffic control requirements where applicable.
All Utilities CIP projects, irrespective of the requirements set forth by the authority having jurisdiction
over traffic control, must have a traffic control plan. These plans are mandatory for all on-site work
and need to be signed and stamped by a California registered professional traffic engineer.
B. Additional Traffic Control Requirements
In addition to the requirements in Transportation Department’s ‘Requirements for Traffic Control
Plan Submission’ manual, all traffic control requirements outlined in this section shall also be
followed. The contractor shall furnish, erect, and maintain sufficient warning and directions signs,
working flashers on each barricade, lighted warning signs, and furnish sufficient flag persons to give
adequate warning to the public at all times in the road or street under construction.
Contractor shall submit traffic control plans, as part of the required pre-construction submittals, to
the Engineer for City’s approval within fifteen twenty (2015) Working Daysbusiness days after from
the Notice of Council ApprovalAward is issuedissuance date. The Notice to Proceed will not be
issued until the traffic control plans and submittals are approved (Allow up to 15 working days for the
approval process) and all other conditions are met. For projects with critical start and/or completion
dates, it is the Contractor’s responsibility to meet the dates requirements by submitting required
traffic control plans in advanceas specified and allow sufficient review timeto avoid delays due to
review time. Liquidated damages will be assessed when Contractor fails to meet the project
milestones and/or Substantial completion.
The traffic control plan shall include a typical intersection and street for work planned with typical
pavement widths and lane widths noted on the plan. The Transportation Department may also
requires site-specific plans on high-volume traffic intersections andor arterial streets. For the
following major signalized intersections and arterial/collector streets, the traffic control plan shall
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 2
reflect actual (not typical) intersection layout and indicate islands, medians, lane lines, bike lane
lines, nearby driveways, and note all pavement and lane widths.: See Section 1500.1.02.B.30 for a
list of arterial and collector streets. Additional streets may be identified in the 'Requirements for
Traffic Control Plan Submission’ manual. Some major street intersections are listed below:
x All Intersections with Page Mill Road, Embarcadero Road, Arboretum Road
x Intersections of Charleston Road/Commercial Street and Coyote Hill Road /Hillview Avenue.
All cost and expense for traffic control shall be included in the Bid prices for various Bid items and no
special compensation shall be allowed.
Contractor shall not detour traffic without the approval of Transportation Department. ‘Closed to
through traffic’ is not permitted on two adjacent parallel streets simultaneously, unless it’s an
emergency, approved by the Engineer, and the contractor received an approved traffic detour plan
from Transportation Department.
The Contractor shall maintain adequate separation between pedestrians, bicyclists, vehicular traffic,
truck traffic, and the work site during construction by providing adequate barricades with at least one
working flasher on each, pedestrian bridges, ramps, reflectors, cones, guard rails, fencing and any
other warning devices as required. The Contractor shall separate truck traffic from bicycle traffic (i.e.
place signs directing bicyclists to an alternate route away from the haul route). Each pedestrian
crosswalk, when crossing by or over construction excavation, shall be provided with a pedestrian
bridge with handrails. The Contractor shall not remove the barricades in the street at any given
location until the final paving repair has been completed and the hazard to bicyclists and motorists
no longer exists.
The Contractor shall coordinate the Work with the appropriate Transit Districts, and School Districts
running the buses in the area and shall notify the Communications once a week about the
construction activities.
The following requirements are minimum and do not limit the Contractor's responsibility of doing all
that is practical and necessary to ensure the safety of workers, pedestrians, bicyclists, and
motorists:
1. Traffic control shall conform to the latest additions of the Manual of Uniform Traffic Control
Devices (MUTCD Caltrans), Work Area Traffic Control Handbook (WATCH BOOK), Traffic
Control ManualRequirements for Traffic Control Plan Submission, and the all applicable City of
Palo Alto Standards.
2. The Contractor is required to submit alternative traffic control plan(s) for day and night work.
3. Local and emergency access shall be maintained on all streets at all times.
4. The Contractor shall protect open excavations, trenches, and such during construction with
fences, covers, and railings, as required, together with signs, lights, and other warning devices
sufficient to maintain safe pedestrian, bicycle, and vehicular traffic to the satisfaction of the City.
5. After each site has been completed, the Contractor at his expense shall restore planting areas
and other areas abutting the work to the condition existing at the start of work. Unless otherwise
authorized by the City Inspector, all construction and restoration including tape striping, signing,
curb markings, etc. shall be completed within fifteen (15) working days from start of work at any
specific location.
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 3
6. The Contractor shall conduct operations and schedule cleanup so as to cause the least possible
obstruction and inconvenience to traffic, pedestrians, cyclists, and adjacent property owners. All
work areas shall be swept clean at the end of each day's work and at other times when directed
by the City. A mobile street sweeper shall be used wherever practical and as required by the
Project Manager, and dust shall be suppressed to the satisfaction of the City. The Contractor
shall remove all debris from the job site at the end of each work day.
7. The Contractor shall notify the abutting property owners at least 15 days in advance and again
24 hours prior to commencing work at their specific locations. The Contractor will be required
to prepare checklists of all notified affected property owners (15 day, and 24 hour
notices) and submit the lists to the Engineer prior to commencing a work at their specific
locations. The notice shall include the project title, contact person(s) and a local telephone
number, and construction dates. The notifications of the construction provided to any
School or Hospital administrations and records of any subsequent contacts with the
School or Hospital administrations, related to the construction, must be maintained and
available for inspection for no less than 5 years from the date of notification. Such
notifications must include name(s) and title(s) of person(s) contacted/notified.
8. Contractor shall maintain access to all driveways except when actually doing construction within
the driveway boundaries, at which time partial access shall be maintained unless alternate
arrangements are made with the property owners or tenants in advance. If the driveway to any
garage or parking area must be closed for construction work, the notice shall state the
approximate time it will be reopened.
9. The Contractor shall post "No Parking" signs as required 72 hours in advance. The signs shall
be approved by the City Police Department and shall specify the date and time “No Parking” will
be allowed. Signs shall be posted a maximum of 50 feet on center and removed immediately
after the work is completed. The signs shall be removed when the work is completed.
10. The Contractor is required to provide a written notification regarding bollards installation to the
affected property owners and submit a notification checklist to the Engineer.
11. The Engineer shall have the right to limit the amount of trench, which may be opened or partially
opened at any time. No more than 500 feet of trench or one City block of trench, whichever is
greater, or more than 50 potholes not to exceed a total paved surface area of 500 square feet,
shall be opened at any one time. Paved surface disruptions shall be classified as open until
final pavement resurfacing has been completed including full surface restoration on the affected
by the construction private property.
12. Temporary pavement markings shall be in place prior to allowing traffic to use the street. This
includes all markings (STOP bars, crosswalks, arrows, and lane line striping).
13. Damage done by the Contractor during the course of the work to City property shall be repaired
and restored to “like-new” condition or, as the Project Manager shall direct, at the Contractor's
expense. This includes the repair of traffic loop detectors, striping, signing, curb markings, etc.
Unless otherwise authorized by the City Inspector, all construction and restoration including
striping, signing, curb markings, etc. shall be completed within one week of work completion.
Loop detectors shall be repaired within 72 hours of damage.
14. Limited stockpiling of materials or parking of equipment during non-working hours will be
allowed on City property, i.e., streets, alleys, parking lots, sidewalks, etc. (refer to Section
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 4
1.05.A) While storing equipment and materials on the street, storage area shall be properly
barricaded and shall not block traffic. Materials shall be placed in such a manner that they do
not impede the flow of water to the storm drains and shall be covered to avoid run-off during
rain.
15. The Contractor will be required to pay for any public off-street or on-street “time-limited” parking
spaces, within the University Avenue and California Avenue business districts or Stanford
University areas that will be rendered unusable to the public as a result of the permitted
operations. This includes spaces to maintain traffic lanes, for parking of construction vehicles
during work hours, for issuing parking permits to parked vehicles displaced from their private
parking spaces, etc. The proposed use of parking spaces must be included in the traffic control
plan submission.
16. All open trench and excavations must be backfilled and paved with temporary asphaltic concrete
or steel-plated at the end of each work day with non-skid plates. The Contractor shall place cold
cutback around the edges of non-skid steel plates and elsewhere as necessary to eliminate
vertical edges. For ADA compliance all cutback on sidewalks shall be placed so there will be a
12:1 slope to allow disabled access.
17. Spillage resulting from hauling operations along or across any public traveled way shall be
removed immediately by the Contractor at the Contractor’s expense.
18. Compliance with the City of Palo Alto Truck Route Regulations is required at all times.
19. Contractor shall obtain a Transportation permit from the Transportation Division for any vehicle
that exceeds weight or dimensions prescribed in California Vehicle Code.
20. Any work along El Camino will require a permit and approval from the State of California
Department of Transportation (Caltrans), and work along Oregon Expressway, Page Mill, and
Foothill Expressway requires a permit and approval from Santa Clara County Transportation
Agency.
21. The contractor shall use only Caltrans-approved traffic control devices. The Contractor shall
supply, place, and maintain all necessary traffic control devices in accordance with the State of
California “Manual of Traffic Controls for Construction and Maintenance of Work Zones”.
22. In general, Contractor shall maintain all vehicular, pedestrian, and bike movements. If possible,
the Contractor shall maintain one lane of traffic in each direction at all times on all streets. The
clear width of the lane shall be a minimum of 10 feet. When a bike lane is closed in conjunction
with a vehicle lane, the clear width of the lane shall be a minimum of 14 feet. No total closure of
any arterial or collector street, business district street, or alley will be permitted. City may allow
closure of local residential streets, but contractor shall always maintain local and emergency
access and provide a signed detour route around the closure.
23. Flashing arrow boards shall be used at all times when shifting traffic to the opposite side of the
street, shifting traffic at night, for work on arterial streets (Middlefield, Alma, Embarcadero,
University, Charleston, Arastradero, Sand Hill, and San Antonio), and as otherwise required in
the approved traffic control plan.
24. All warning signs and cones for night lane closures shall be illuminated or retroreflective.
Retroreflection of 28-inch cones shall be provided by a 6” white band and a 4” white band.
Flashing warning lights shall be used for all night lane closures.
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 5
25. Contractor shall use “Bike Lane Closed Ahead” and “Bike Lane Ends” signs when necessary to
close bike lanes. Detour signs shall be provided for any Class I bike path closure.
26. Work shall not restrict visibility of any traffic control device.
27. A minimum four feet (clear) sidewalk shall be maintained unless the work makes closure
unavoidable, in which case the sidewalk may be closed while working, subject to the approval of
the Project Manager. During sidewalk closures, R96 “No Pedestrian” signs shall be posted at
the site and R49M “Sidewalk Closed – Use Other Side” signs posted on both sides of the site at
the nearest corners. If the other side of the street is not available or practical for pedestrian use,
an alternate pedestrian facility shall be provided for the duration of the closure. The alternate
facility shall conform to construction requirements of the Uniform Building Code (UBC) and the
Americans with Disabilities Act (ADA). At intersections, work will be permitted at one corner at a
time, so pedestrian movements can be maintained through the intersection.
28. The construction hours for Utilities CIP project are generally 8 AM to 4:30 PM, Monday through
Friday, unless otherwise noted. Refer to City’s Traffic Control Manual and Requirements for
Traffic Control Plan Submission for further time restrictions in downtown areas, business
districts, on arterial streets, in bike lanes, and near schools.
28.29. All work within 1500 feet of the school or hospital shall be coordinated with the
school or hospital administration. No work will be permitted within 1500 feet of school
grounds or along school routes, as shown on adopted Walk and Roll Maps, until after 8:3045
a.m. on school days (see latest PAUSD School Year Calendar). Other special restrictions may
be required at heavily used school crossings or school commute routes beyond 1500 feet from
the school grounds, as deemed necessary for student safety by the Project Manager.
29.30. Work on arterial and collector streets will not be permitted between the
hours of 7:00 and 9:00 AM and 4:00 and 6:00 PM. The restricted streets include: Alma St,
Arastradero Rd, Arboretum Dr, California Ave, Channing Ave, Colorado Ave, E Bayshore Rd, E
Charleston Rd, E Meadow Cir, E Meadow Dr, Embarcadero Rd, Fabian Wy, Louis Rd,
Middlefield Rd, Palo Alto Ave (west of Alma St), San Antonio Rd, Sand Hill Rd, University Ave,
Hansen Wy, Hillview Dr, Park Blvd, Stanford Ave, Quarry Rd, W Charleston Rd, Bayshore Rd W
Meadow Dr, and Welch Rd. Any exceptions to these must be approved by both the Public
Works Department and Planning and Community Environment Department – Transportation
DivisionAlma Street, Embarcadero Road, Middlefield Road and Oregon Expressway will be
permitted between the hours of 9 a.m. and 4 p.m. only.
31. Projects affecting motor vehicle, pedestrian or bicycle traffic in business districts is generally
only permitted between the hours of 9:00 AM and 4:00 PM. Business Districts include the
following areas:
x University Ave District (Downtown):
bounded by Alma St, Webster Ave, Lytton Ave, and Forest Ave
x California Ave District:
bounded by El Camino Real, Caltrain corridor, Sherman Ave, and Cambridge Ave
32. No closure of any lane within 200’ of signalized intersection will be permitted between 7 A.M. to
9 A.M. and between 4 P.M. to 6 P.M. In addition, work will not be allowed at or within 200' of
signalized intersections between 11:30 A.M. and 1:00 P.M.
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 6
30.33. If work will impact transit stops or transit routes, contractor shall be required
to contact Santa Clara County Transit District, Samtrans and other affected transit companies to
address relocation of facilities or rerouting of buses prior to submitting traffic control plan. Traffic
control plan should indicate what actions are being taken with regard to transit services.
31.34. Any work within 150 feet of any signalized intersection shall be coordinated
with the City of Palo Alto Traffic Signal Supervisor at (650) 496-6991.
32. No closure of any lane within 200’ of signalized intersection will be permitted between 7 A.M. to
9 A.M. and between 4 P.M. to 6 P.M. In addition, work will not be allowed at or within 200' of
signalized intersections between 11:30 A.M. and 1:00 P.M.
33.35. Traffic shall be fully restored outside the permitted work hours, unless
approved Traffic Control Plan modifies work time limitations. Violation of any of the above listed
restrictions will lead to a penalty charge to the Contractor at the rate of $200/hour.
34.36. Any work in vicinity of a signalized intersection within Caltrans R/W shall be
coordinated with Caltrans Signal Operation Division and performed in accordance with the
conditions of and encroachment permit.
35.37. Except in emergency situations, any traffic detour requires five (5) working
days advanced notice in order to insure proper advanced planning.
36.38. The contractor shall place barricades 50 feet on center at the gutter joints
and provide one working flasher for each barricade and shall insure that each flasher is
maintained in working condition while in use. The Contractor shall not remove the barricades in
the street at any given location until the asphalt concrete patching adjacent to the gutter and/or
gutter overlay has been done and the hazard to bicyclists and motorists no longer exists.
37.39. Flaggers shall be equipped with a hard hat, an orange vest, and a C28
“STOP/SLOW” paddle on a 5-foot staff. Additional advance flaggers may be required when
traffic queues develop. Flagger stations for work at night shall be illuminated as noted in
Section 5-04.6 of the Manual of Traffic Control for Construction and Maintenance Zones.
38.40. The Contractor may be required, at Contractor’s own expense, to hire City
of Palo Alto Police Officers to direct traffic if the traffic signals at an intersection or crossing
become inoperable due to the Contractor’s work, traffic control setup does not conform to the
approved traffic control plan, or if the Project Manager determines that Police Officers are
necessary to safely guide traffic through the intersection.
1.03 SAFETY
All work shall be conducted in a safe manner and in strict accordance with the rules of the State Division
of Industrial Safety (Cal OSHA). The Contractor shall take all reasonable precautions necessary to
protect from personal injury all workers and other persons who may be in or about the construction area
and to prevent damage to both public and private property. Workers in the public right-of-way shall wear
orange safety vests and hard hats at all times.
The Contractor shall assume sole and complete responsibility for job site conditions during the course of
construction of this Project, including safety of all persons and property; that this requirement shall apply
continuously and not be limited to normal working hours; and that the Contractor shall defend, indemnify
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 7
and hold the City harmless from any and all liability, real or alleged, in connection with the performance
of work on this Project.
The Contractor shall notify the City in writing of all accidents arising out of work performed under this
Contract and shall submit to the Engineer a detailed report of each such accident within 24 hours of the
event.
The Contractor shall protect open excavations, trenches, manholes, and such during construction with
steel plating, fences, covers, and/or railings, together with adequate barricades with at least one working
flasher each, signs, lights, and other warning devices, sufficient to maintain safe pedestrian, bicycle and
vehicle traffic. The warning devices shall not be removed until the asphalt concrete patching adjacent to
the gutter and/or gutter overlay has been completed and the hazard no longer exists.
If, in the opinion of the Engineer, some portion of the work is being done in an unsafe manner, the
Engineer may order that portion of the work stopped until proper methods have been adopted by the
Contractor to make it safe.
The duty of the Engineer is to conduct construction review of the Contractor's performance and is not
intended to include review of the adequacy of the Contractor's safety measures on or near the
construction site. Nothing in this Section shall operate or be construed to impose any text or contractual
liability on the City or its employees for the Contractor's safety responsibilities.
The above requirements are a minimum and do not limit the Contractor's responsibility of doing all that
is practical and necessary to ensure the safety of workers, pedestrians, bicyclists and motorists.
1.04 SANITATION FACILITIES
Temporary Sanitation facilities, required for construction personnel, shall be provided by the Contractor.
Temporary Sanitation facilities shall be on a trailer and transported to-and-from the active jobsite daily.
The Contractor shall apply for an encroachment permit where a Temporary Sanitation facility remains
unhitched and left at the jobsite beyond the defined work hours. Contractor shall maintain sanitation
facilities on a weekly basis or more frequently if required. If there are any odor complaints, the
Contractor shall clean and move sanitation facilities to another location.
1.05 STORAGE OF EQUIPMENT AND MATERIALS
A. Contractor Off-Site Storage Area
The contractor is required to secure an offsite storage area suitable to store equipment, structures,
pipe and granular material. The cost associated with securing an off-site storage area must be
included in one or more of the contract bid items.
Furthermore, contractor access and work at the offsite storage area within Palo Alto City limits shall
meet County of Santa Clara and/or City of Palo Alto’s best management practices including but not
limited to: tarping new material piles; wetting down storage area to mitigate dust; tarping
spoils/offhaul material piles; and off hauling spoils dailyat least once per week. Unless in a
commercially zoned area, work hours for access to the storage area shall be limited to 8:00AM-
5:00 PM Monday through Friday. Saturday access shall be from 9:00AM to 5:00PM. No site access
shall be permitted on holidays or dates that the City cannot provide inspection coverage as stated
in the Special Provisions.
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 8
B. Policy for Storage of Equipment, Pipes, Structures and Granular Materials in the Public
Right-of-Way
All storage in the public right of way shall be performed in strict compliance with City of Palo Alto
Public Works Policy for storage of equipment, pipes, structures and granular materials in the public
right-of-way.
Contractor shall adhere to all of the City’s on-site storage policies. The City has the right to revoke storage of materials and equipment within the City’s Right-of-Way for non-compliance with the City’s storage policies.
Within the City’s Right-of-Way, the Contractor is only permitted to store up to four (4) construction
vehicles or equipment (excavators, backhoes, wheel loader, skid steer, etc.) beyond the work hours defined for the project, regardless of crew size or location. Paving rollers will only be allowed
to be stored within the City’s Right-of-Way every two weeks for a maximum duration of two days and only when paving is scheduled.
Trench plates and backfill material that is planned to be used for the current week’s scheduled
work may be stored within the Public Right-of-Way beyond the work hours defined for this project. Contractor shall coordinate with the City’s inspector(s) to identify a suitable location to temporarily
store material and equipment.
All equipment and material temporarily stored at the construction site, within the Public Right-of-Way, shall be relocated to the active job sites and cannot remain at any given jobs sites where
after the work is completed. In addition, all granular material shall be removed at the end of each work week and before rainfall starts. If a complaint from the public is received by the City regarding the Contractor’s equipment or materials, the contractor shall may be directed to relocate or remove all equipment and/or material
from the City’s Right-of-Way.
Prior to storage of any equipment or material, Contractor shall notify the City Inspector(s) of the
proposed equipment or material storage sites and request the City Inspector(s) to take pictures
and/or video of the storage sites. If Contractor fails to provide this notification, Contractor shall be
held liable for any damage sustained by the storage site and be responsible for site restoration to
preconstruction conditions as directed by the Inspector(s).
C. General Storage Requirements
It is the Contractor's responsibility to locate a site for the storage of equipment, materials, and office
facilities and to obtain and pay for all permits and fees necessary to make the site legal for storage.
The Contractor shall not store any equipment or material on private property zoned for residential
use. This includes commercial and industrial lots adjacent to residential property.
Any commercial or industrial property being considered as a storage site will require proper permits
from Planning & Development Services Department.
Equipment and materials, which are part of the Contract, shall be protected and stored in
accordance with the recommendations of the manufacturer. The Contractor shall assume the risk
of loss or theft of or damage to all equipment and materials delivered to or accepted by him or her
until such equipment and materials have been completely installed and accepted by the Engineer.
Storage in public right of way will not require an Encroachment Permit, but will require the prior
approval of the appropriate authority.
1. Additional Requirements
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 9
a. Equipment, pipe, structures, and granular materials shall be placed within one block of
the location where it is to be used, but no less than three blocks or 1000 feet from an
adjacent non-related project. Alternate locations may be determined by the appropriate
authority if construction and traffic conditions warrant.
b. Equipment, pipe, structure, and granular materials shall not block access to or visibility
of any fire hydrants, driveways, traffic signs, utilities, intersections, sidewalks, bike
lanes, crosswalks or drainage paths.
c. A minimum pavement width of 24 feet shall be maintained for traffic purposes.
d. No equipment, pipe, structures, or granular materials shall extend more than eight feet
into the street from the face of the curb and in no other case shall extend more than
one third of the roadway.
e. Two (2) type II barricades, with working flashers, shall be placed at each end of the
storage area.
f. One (1) type II barricade, with working flasher, shall be placed at 25-foot intervals along
the street side of the storage area.
g. Only the amount of pipe and structures that can be installed and back-filled in five (5)
consecutive days shall be stored in the public right-of-way.
h. Pipe or structure that can be easily lifted by hand and weighing less than 200 pounds
shall not be stored in the public right-of-way.
i. Steel deck plates shall not be stored in the public right-of-way.
j. Contractor shall hand deliver advance notice door hangers to businesses, residents, or
others, at locations where equipment, pipe, structures, and granular materials will be
stored, at least seven days in advance of the storage date. City will provide required
notices.
2. Trucks and Equipment
a. Equipment is defined as, but not limited to, backhoes, trenchers, loaders, rollers, self-
propelled pavers, and graders.
b. Only equipment in good mechanical condition shall be stored in the public right-of-way.
c. Any equipment that can not be repaired by the end of the day shall be removed
immediately from the public right-of-way.
d. Fluid leaks shall be repaired prior to the end of the day.
e. Spilled fluids shall be cleaned-up and disposed of in accordance with applicable
hazardous waste laws.
f. All equipment and materials shall be removed at the request of the Engineer for reasons
related to weather, job shutdown, safety or reasonable complaints and requests from
residents, and/or business owners.
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 10
g. Trucks and portable equipment, such as generators, compressors, and arrow boards,
shall be removed at the end of the day.
3. Granular Material
a. Granular material, such as backfill, bedding and cutback shall be placed against an
appropriate portable barrier, such as k-rail, to protect the curb and improvements
behind the curb.
b. The barrier shall be located a minimum of one foot in front of the face of the curb, so as
not to obstruct the drainage of water, unless otherwise directed by the Engineer.
c. No more than the amount of granular material that can be used in two (2) consecutive
days shall be stored at any time.
d. No granular material shall be stored within ten (10) feet of any catch basin or curb
return.
e. Granular material shall not be allowed to enter the storm drain or sanitary sewer
systems.
f. A tarp covering the granular material and sandbag berms placed around the granular
material shall be used as required by the Engineer during rainy periods.
g. The job site shall be swept clean at the end of the workday. An Athey Mobile Street
Sweeper Model AHL M9 or an approved equal shall be used.
1.06 CLEANUP
A. Daily
The Contractor shall not allow the job site to become littered with trash and waste material but
shall maintain the site in a neat, orderly, and dust free condition on a daily basis, or as required
by the Engineer, throughout the construction period. The Contractor shall conduct his or her
operations and schedule cleanup so as to cause the least possible obstruction and
inconvenience to vehicle, bicycle or pedestrian traffic, and adjacent property owners.
All work areas shall be kept in a dust-free state. A mobile street sweeper shall be used daily to
maintain a dust-free condition. At the end of each working day all work areas shall be swept
clean by an Athey Mobile Street Sweeper Model AHL M9 or an approved equal, subject to the
approval of the Supervisor of the Public Works Inspection Group.
All landscaped areas shall be left with a neatly graded surface, conforming to the adjacent
existing ground. All sidewalks should be manually swept to maintain a dust-free condition.
Spilled fluids shall be cleaned up and properly disposed of immediately, using an appropriate
absorbent material, by the Contractor at the Contractor's expense.
Spillage resulting from the Contractor's hauling operations along or across any public traveled
way shall be removed immediately by the Contractor at the Contractor's expense. All hazardous
materials shall be cleaned up per the Fire Department’s and Public Works Department’s policies,
and all applicable hazardous waste laws and regulations.
B. Final
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 11
Execute final cleaning prior to final inspection.
1. Clean all furnished equipment to insure proper operation; remove temporary labels, stains,
and foreign substances.
2. Clean site; sweep paved areas.
3. Remove waste, surplus materials, and rubbish from project sites to proper legal disposal
areas selected by Contractor so that the entire job site and all areas that were occupied by
Contractor during the project are restored to pre-job conditions.
4. Existing buildings, street furniture, equipment, piping, pipe covering, paving, sewer laterals,
sewers, trees, curb and gutter, sidewalks, landscaping, sprinkler systems, bridge abutments,
gas and water services, etc., and other public and private property damaged by the
Contractor during the course of his work shall be replaced and/or repaired either by the City
or the Contractor at the Contractor’s expense.
5. The Contractor shall completely remove all remaining USA markings and all other markings
associated with this project from pavement, sidewalk, curbs, driveways, etc.
1.07 SIGNAGE
At the beginning of each workday, the Contractor shall provide project signs for the ends of each
location/street where work is being performed. Signs shall include name of Contractor, Contractor
contact information, name of project, dates of work, and work hours (may vary depending on the
project location). It is the Contractor’s responsibility to move the signs as the project progresses. All
costs of project signs, and the associated labor costs to place and move the signs as the project
location changes, must be included in one or more of the Bid items. No additional compensation shall
be paid to the Contractor for project signs.
Sign Specifications:
Size: 3’ X 5’
Color: black letters on white reflective background w/ black border.
Letters: black, 1" min height, 1/4" thick Arial font, spacing approx. as shown below.
Dates or work and work hours shall reflect the correct information at each project location.
Each sign shall be attached to a barricade which can be moved from one construction site to the
next. An information box (see attached .gif file) shall also be attached next to the sign. The City will
provide the information letters. The Contractor shall provide the box.
Sample Sign:
SITE AND TRAFFIC CONTROL SECTION 1500
CITY OF PALO ALTO Section 1500 PAGE 12
Project Name
Month Year – Month Year
Monday- Friday 8 am to 5 pm
Contractor’s Name
Contractor’s Local Phone Number
Project Website: https://www.cityofpaloalto.org/Departments/Utilities/Utilities-Services-Safety/Utilities-Projects
END OF SECTION
City of Palo Alto
Utilities Department
(650) 566-4501
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 1
SECTION 2200
EXCAVATION, BACKFILL, AND RESTORATION
PART 1 - GENERAL
1.1 DESCRIPTION
Excavation, backfill, and restoration shall conform to the City of Palo Alto Department of Public
Works Standard Drawings and Specifications, and as specified on the project plans. Excavation
and backfill shall conform to the safety requirements of the Contract and the approved traffic control
plans.
1.2 WATER AND WASTEWATER MAINS OR SERVICES INSTALLED BY DEVELOPMENT
SERVICES APPLICANTS
For applicant-installed water and wastewater mains or services (gas shall only be installed by Palo
Alto Utilities crews or City Contractor), the applicant shall submit the following to the WGW
engineering section of the Utilities Department:
A. Electronic copy of the installation of water and wastewater utilities off-site improvement plans
in accordance with the Utilities Department design criteria. All utility work within the public right-
of-way, or the public portion of the utilities, shall be clearly shown on the plans that are
prepared, signed and stamped by a registered civil engineer.
B. A complete schedule of work.
C. Method of construction including abandonment details.
D. The manufacturer's literature on the materials to be used for approval by the Utilities
Engineering Department.
E. PE pipe fusion certification by City-authorized testing company or personnel.
The applicant's contractor will not be allowed to begin work until the improvement plan and other
submittals have been approved by the Water, Gas and Wastewater Engineering Department.
WGW inspections shall be scheduled at least five (5) days in advance.
After the work is completed, but prior to sign off, the applicant shall provide record drawings (as-
builts) of the installation of water and wastewater utilities to be owned and maintained by the City.
PART 2 - BACKFILL AND RESTORATION MATERIALS
Contractor shall prepare submittals for sand, 1/2" crushed rock, 3/4" aggregate base, and controller density
fill (CDF), for Engineer's approval. The Contractor shall also prepare all submittals required by Public Works
Department per Public Works Standard Drawing and Specifications.
2.1 BACKFILL
All backfill materials shall comply with the drawings and be in accordance with the latest edition of
the California Department of Transportation, Standard Specifications. Excavated material shall not
be used for pipe bedding or trench backfill.
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 2
2.2 SAND
Sand shall conform with Section 19-3.02FE(2) of the latest edition of the Caltrans State Standard
Specifications and shall be imported clean natural sand, free from clay, salt, sea shells, or organic
material, suitable for the purpose intended and shall conform to the following gradation:
No. 4 sieve…………… 90% - 100%
No. 200 sieve………… 0% - 5%
Dredged sand from San Francisco Bay is not acceptable.
2.3 Class 3 Permeable Material (1/2" CRUSHED ROCK)
1/2" crushed rock will be designated by nominal size and shall conform to the following gradation
when tested in accordance with sections 6 and 68-2.02F(4) of the latest edition of the Caltrans
State Standard Specifications
Class 3 permeable base:
Passing a 1-1/2” sieve………….............. 100%
Passing a 1” sieve………………………. 88% - 100%
Passing a 3/4” sieve…………………….. 52% - 85%
Passing a 3/8" sieve............................... 15% - 38%
Passing a No. 4 sieve............................ 0% - 16%
Passing a No. 8 sieve............................ 0% - 6%
This material shall contain at least 75% of the particles having one or more fractured faces. Not
over 25% shall be particles showing no such faces.
Crushed rock shall meet the test grading requirements of ASTM C 131 test grading B.
2.4 Class 2 Aggregate Base (3/4”)
Class 2 (3/4") will be designated by nominal size, shall conform to the following gradation, and shall
meet the requirements of Sections 6 and 26-1.02B of the latest edition of the Caltrans State
Standard Specifications:
Passing a 1” sieve………………………...100%
Passing a 3/4" sieve............................ 87% - 100%
Passing a No. 4 sieve.......................... 30% - 65%
Passing a No. 30 sieve.......................... 5% - 35%
Passing a No. 200 sieve...................... 0% - 12%
2.5 CONTROLLED DENSITY FILL (CDF)
A. Materials:
1. Cement: ASTM C150, Type II or V, 1-1/2 to 2 sack mix.
2. Aggregate: Mixture of clean sand and pea gravel, 3/8 inch maximum size.
3. Fly Ash: ASTM C-618 Class F.
4. Water: Potable water or water of similar quality which is free of deleterious impurities.
5. May use suitable admixture(s).
B. Mix Design and Performance:
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 3
1. CDF shall be non-segregating, flowable, self-consolidating, low-shrink material that flows
into place without leaving voids and cures into a stiff non-plastic material.
2. Compressive strength: 28 day strength between 50 psi and 200 psi.
3. CDF shall be supplied by a concrete manufacturing plant.
4. Place CDF so as not to float the pipes.
C. Submittals:
1. Mix design.
2. Samples of the material to be used.
3. Results of laboratory trial mix compressive strength testing using 6” diameter by 12” test
cylinders with cylinder breaks at 7 and 28 days (28 day test shall be average of 2 or more
cylinder breaks).
PART 3 - EXECUTION
3.1 EXISTING UTILITIES AND USA
The Contractor shall comply with IFB Part 5 General Conditions 3.28 and additional requirements
in this section for Underground Service Alert (USA). For Utilities projects, it is the Contractor's
responsibility to notify Underground Service Alert (USA at 811) a minimum of ten (10) Working
Days in advance of starting excavation. The Contractor shall delineate the areas of work with white
paint. Contractor shall only request utility markings at those locations where underground work will
occur during the following month.
Prior to excavation, the Contractor shall verify that all utilities shown in the contract documents or
observed in the field from existing aboveground utility features, have been USA-marked. Notify
USA and schedule a meet and mark at least three (3) working days prior to excavation, if any utility
has not been marked, has been marked differently than what’s shown in the project plans, or the
marking appears to be inaccurate judging by the existing aboveground features for the utility. If the
Contractor is unable to locate identified underground utilities while excavating, based on USA
marks or information provided in the contract documents, the Contractor will contact the responsible
utility owner to locate those facilities.
Where underground utility mains such as water, gas, wastewater, electric, telephone, or cable
television are shown on the project plans, the Contractor shall assume that every property parcel
adjacent to or on the same street as the underground utility mains has an underground service for
each type of utility present. In addition, the Contractor shall assume that each property parcel with
either an above ground or at grade facility, such as a water meter box, gas meter, or sanitary sewer
clean out, has an underground service for the respective utility. If a service is not shown on the
project plans for any parcel, not marked, or marked in the incorrect location according to the project
plans, the Contractor shall bring it to the attention of the WGW Utilities Inspector at least three
working days prior to digging to allow time to resolve the conflict.
If USA re-marking is required due to any reasons, the Contractor shall anticipate up to two (2)
working days turn-around time. No additional compensation for standby or waiting time shall be
paid to the Contractor, subject to the limitations set forth in Public Contract Code section 7102, if
applicable.
The Contractor shall completely remove all USA markings and all other markings associated with
this project from pavement, sidewalk, curbs, driveways, etc. The method used for removal of the
markings shall be approved by the City. The cost to remove the USA markings shall be included in
one or more Bid items and no extra compensation shall be paid to the Contractor.
Methods of protection of existing utilities shall be approved by the Engineer prior to the start of
crossing the existing utilities. All utilities crossing or lying along the trench shall be supported. The
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 4
work of bracing and the care of all encountered utilities below grade shall be considered a part of
excavation and backfill.
If it is necessary to relocate or temporarily remove and replace existing underground utilities, the
Contractor shall first obtain permission from the utility concerned and comply with its requirements
in performing the necessary work. Gas and water line relocations shall be performed by the City.
All costs incurred shall be paid by the Contractor. Property owners shall be notified at least 24
hours before the planned disruption of any utility service.
Shut down of City WGW Utilities shall be performed by City of Palo Alto Utilities WGW Operations
Division. The Contractor shall not disconnect or shutdown any part of the existing City of Palo Alto
WGW Utilities System except by expressed written permission of the Engineer. Notify the Engineer
five (5) working days in advance of required shutdowns and submit a schedule of the estimated
shutdown time to obtain said permission.
The contractor shall pothole all crossing and nearby parallel utilities both public and private within
the work area. The Contractor shall proceed with caution during the trenching operation to avoid
damage to the existing underground utilities. Caution must also be exercised when installing new
pipe by directional boring methods. All existing utilities crossing the proposed bore path must be
prospected prior to establishing the pilot bore path. Locator devices, careful probing, vacuum, and
hand methods of excavation shall be employed to determine the exact horizontal or vertical
alignment of underground facilities. All exposed gas lines and electric facilities shall be inspected
for damage by the WGW Utilities and Electric Utilities Inspectors prior to backfill. The Contractor
shall immediately notify the Engineer if any Underground Facility is disturbed or damaged.
Repairs to existing City wastewater utilities shall be performed by the Contractor, unless otherwise
directed by the Engineer. City forces shall repair, relocate, or replace all other City utilities. The
Contractor shall accommodate City forces in his or her operations. The Contractor shall pay for
the full cost to repair the existing utility mains or services, public or private, damaged by
his or her operations and any other damages resulting from the damaged utilities when the
damage is due to the Contractor’s failure to exercise reasonable care with utilities that are
indicated in the plans and specifications with reasonable accuracy.
The Contractor shall take extreme caution when excavating adjacent to electrical conduits/wires,
fiber optic conduits/wires, and traffic signal loops/conduits/wires. The Contractor is expected to
carefully crack the concrete and hand-dig when excavating around traffic signal conduits, as they
may be shallow and often embedded in concrete and/or asphalt road surface. When a conduit cut
or dig-in occurs, the Contractor shall postpone excavating around the conduits to avoid further
damage until Electric Operations assesses their condition and repairs are performed. Any damage
to electrical conduits, fiber optic conduits, or traffic signal loops and conduits shall be repaired by
the contractor at no cost to the City. Any damage to electrical substructure/cable/wires, gas lines,
or water mains will be repaired by the city and the cost will be paid by the Contractors. An electrical
Inspector shall be present while the contractor repairs electrical, fiber optic, or traffic signal
conduits. The Contractor shall contact Electric Operations Dispatch at 650-496-6914 to schedule
electrical inspection.
The cost of repairs performed by City crews will be billed to the Contractor by the WGW or Electric
Operations Division and shall be paid independently by the Contractor to the City's WGW or Electric
Operations Division. Payment must be made when submitting monthly progress payment request.
Final project approval or payment will not be made until these bills have been paid.
Wrapping on any exposed steel gas lines shall be inspected by the City prior to backfill. Repairs of
customer-owned sprinkler systems shall be made by the Contractor at their own expense.
Contractor shall repair customer-owned portions of water and gas services damaged by the
Contractor, at the Contractor’s sole expense. The repair work must be performed by a licensed
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 5
plumber in accordance with the requirements of UPC and City of Palo Alto Building Inspection. The
Contractor will be responsible for coordinating access to private property with the owners.
3.2 POTHOLING
The contractor shall locate and pothole all existing crossing utilities and parallel utilities within 5
feet of the proposed designed pipe alignmentutility in the work area. For parallel utility potholing,
the Contractor shall pothole at least every XX ft or if the parallel run is less than that value, one
pothole shall be performed. The Contractor shall pothole and confirm there is sufficient vertical or
horizontal separation between the existing utilitiesy and the designed pipe alignment at least three
(3) working days prior to performing any construction activities for the proposed pipe.
x ies beyondIf the existing crossing or parallel utility is at a higher elevation than the designed
pipe elevation, the Contractor shall daylight and expose the bottom of the existing
pipe/conduit/duct/duct bank.
x If the elevation of the existing crossing or parallel utility is at a lower elevation than below the
designed pipe elevation, the Contractor shall expose the top of the existing utility or expose to
the bottom of the existing utility for non-City of Palo Alto owned utilities.
x For parallel utilities, the Contractor shall pothole every 100 feet until the utility is beyond the 5-
foot parallel zone.
x The Contractor shall allow the Inspector or Engineer to have clear visual of the existing utility
in each pothole as the drilling or bursting head passes through the existing utility. This is to
ensure that the existing utility/structure is not damaged by the drilling/bursting operation.
x at a higher elevation thanFor third party utilities such as PG&E’s high pressure gas mains, the
Contractor shall comply with the utility owner’s potholing requirements.
The Contractor is required to fully examine and inspect the project site and have full knowledge of
the physical conditions of the project area prior to submitting the bid. For public or private utilities
that are not shown on the project drawings but can be anticipated from the presence of other visible
features or facilities, the Contractor should include the cost under one or more bid items to locate
and pothole these utilities in the project area. The Contractor shall pothole as required to determine
the exact locations and elevations of existing utilities at least three (3) working days prior to any
construction activities for the proposed pipe at the subject location to allow sufficient time to resolve
potential issues. Using the USA markings as a guide and/or in agreed-upon locations with the City
Inspector, the Contractor shall make at least two (2) potholes to locate each utility, public or private,
before the City will consider additional compensation for extra work or delays. The Contractor shall
anticipate a 2-day turn-around time for re-marking of public or private utilities. See Part 3.01
(Existing Utilities and USA) of this Specification for additional information on USA marking
requirements.
For trenchless construction, all potholed existing crossing and parallel utilities shall remain exposed
and visible throughout the boring or pipe-bursting operation and shall be inspected by the WGW
Utilities Inspector and/or Public Works Inspector during the trenchless operation or prior to backfill.
It is the Contractor’s responsibility to investigate any unknown or conflicting utilities and to contact
any the public or private utility agency or owner to resolve the conflicts if conflicts are found
identified during potholing activities. The City is not responsible for any delays or additional costs
associated with unmarked third-party utilities.
3.3 Gas Main Replacement Projects
Pre-Installation CCTV Inspection
Prior to installing new gas pipelines by trenchless methods, the Contractor is required to use a
CCTV camera through any sewer main meeting the criteria listed below, to accurately document
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 6
and mark all lateral connection points and identify the alignment of all sewer laterals on public and
private properties.
x Sewer mains with any connecting sewer lateral that will be crossed by the proposed gas
pipelines.
x Sewer mains with any connecting sewer lateral that is serving the same property as the
proposed gas pipeline or stub.
x Sewer mains with any connecting sewer lateral that is on an adjacent property, but within 10
feet of a proposed gas pipeline.
Contractor shall submit the CCTV logs and video footage for each sewer main with the monthly
progress payment request.
If the Contractor’s CCTV inspection of the sewer pipelines show the pipeline is blocked by roots or
debris, Contractor shall clean the sewer pipeline by flushing until CCTV inspection can be
completed. See Section 2739 “Cleaning and Video Inspection of Sewer Pipe” for requirements. If
there are any obstructions in the sewer main that deemed by the Engineer as unable to be
addressed by cleaning, Contractor shall provide City Operations crew 10 business day notice to
schedule time to assist Contractor with removal of obstructions.
Post-Installation CCTV Inspection
On natural gas main and service replacement projects using trenchless installation methods, post-
installation cross-bore CCTV inspection must be performed on public and private sewer pipelines
when:
x The newly installed gas pipelines cross sewer pipelines.
x The sewer pipelines are serving the same property as the newly installed gas pipeline or stub.
x The sewer pipelines, on an adjacent property, are within 10 feet of a newly installed gas
pipeline.
See Section 2741 “Legacy Cross Bore Inspections Guidelines” and Section 2739 “Cleaning and
Video Inspection of Sewer Pipe” for requirements.
Once installation of the new gas pipelines has been completed using trenchless installation
methods, the Contractor shall perform CCTV inspections to positively verify and document that no
sewer pipelines were damaged during installation. City and private sewer clean-outs may not
always be accessible or present; therefore, the Contractor shall use lateral-launch and push
camera equipment to inspect all sewer pipelines, including sewer pipelines that were not USA
marked or shown on the project plans. All sewer pipelines must be CCTV-inspected and cleared
of a cross-bore, per Specification Section 2741, prior to the City performing gas tie-ins. The
Contractor is also required to perform CCTV inspection of sewer pipelines at all properties where
reconnection is specified, regardless of length of newly installed gas service.
The video inspection must include entire length of the sewer lateral from the wastewater main to
the foundation of the structure or extend three (3) feet beyond the furthest gas riser, whichever is
furthest. Inspection must include sewer lateral branches and cleanout risers. Inspection length will
be determined by the City Inspector assigned to the project. For each sewer pipeline inspection,
the Contractor shall make at least two attempts using the push camera and at least two attempts
using the lateral-launch camera. If using push camera or lateral launch equipment is not successful
following the repeated attempts, the Engineer may request the Contractor to pothole to clear the
sewer lateral from a cross-bore.
If the Contractor’s CCTV inspection of the sewer pipelines show the pipeline is blocked by roots or
debris, Contractor shall clean the sewer pipeline by flushing until CCTV inspection can be
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 7
completed. In the event a portion of the sewer pipeline is not cleared and all efforts to CCTV inspect
the sewer pipeline have been exhausted:
x If the sewer pipeline and newly installed gas pipeline crosses, the Contractor will be directed
to excavate the crossing and have the City Inspector visually verify the separation between the
pipelines.
x If the sewer pipeline and newly installed gas pipeline do not cross, a proximity clearance may
be determined by the City Inspector assigned to the project. If a proximity clearance cannot
be determined, Contractor may be instructed to excavate and expose the entire length of the
gas pipeline for visual inspection.
If the Contractor is unable to find an existing City or private sewer clean-out and inspection efforts
have been exhausted, the City may direct the Contractor to expose the sewer lateral and install a
sewer cleanout per City Utility Standard Details WWD-02A and WWD-02B to facilitate video
inspection. The newly installed sewer cleanout must be inspected and approved by the City
Inspector. The Contractor will be compensated for this Work based on the applicable unit pricing.
If the sewer pipeline is blocked by existing damage or protruding taps, Contractor must provide an
image and location of each section for City Operations to investigate. In the event City Operations
is unable to address the sewer pipeline repair, Contractor may be directed to make the repair on
the sewer pipeline to facilitate the video inspection. Contractor shall receive approval from the City
prior to attempting to repair, clean or cut roots from the sewer pipelines. The Contractor will be
compensated for this Work based on the applicable unit pricing.
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 8
3.4 SAWCUTTING, DEMOLITION, AND REMOVAL FOR UTILITIES CONTRACTS
Trenching shall include the removal of all materials or obstructions of any nature, including asphalt
and concrete pavement. Areas in which sawcutting is performed shall be wet vacuum cleaned
to remove the cutting residual, inclusive of the sawcutting fluid. Sawcut slurry shall not be
permitted to enter storm drains. Areas in which sawcutting is performed shall be cleaned to
remove the cutting residual, inclusive of the sawcutting fluid, at the end of each workday or more
often as required by the Engineer.
Existing street sections shall be removed in such a manner so as not to destroy or damage the
structural integrity of the adjacent street section. Trench cutting shall be accomplished by using a
pavement saw, cutting through the full pavement thickness of the pavement section. No equipment
mounted pavement breakers shall be used. The top portion of the trench (i.e. the pavement
thickness) shall be twelve inches wider than the portion extending to the bottom. Lines shall be
marked along each side of the trench 6" beyond the edge of the trench and the pavement cut along
these lines. To achieve the "T" section required by the City of Palo Alto Public Works Standard
Drawings and Specifications "Typical Trench Sections" detail, generally four (4) parallel sawcuts
are necessary for any given trench. Removal of concrete sidewalks, driveways, curbs, and gutters
shall be to existing joints or to sawcuts made at existing score marks. Tunneling under street,
sidewalk, curb and gutter is not permitted except with directional or percussion bore devices and
as noted on the construction plans.
All pavement broken out of the trench will be removed by jackhammer, ripper teeth or backhoe. No
equipment mounted pavement breakers will be allowed due to the minimal cover over some
existing utilities. Valve boxes over abandoned utility main valves shall be removed from the street
sections, the risers filled with jetted sand, and the street section restored to match the existing
section.
Where the trench is to be located in a Portland cement concrete or asphaltic-concrete paved street,
lines shall be marked along each side of the trench and the pavement cut along these lines with a
concrete saw to the full thickness of the concrete. Only concrete saws for PCC-based pavement
shall be used to remove PCC pavement.
It is the Contractor’s responsibility to locate a suitable disposal or recycling site for all material
removed from the trench. Asphalt concrete and Portland cement concrete must be disposed of at
an inert solids recycling facility, approved by the Engineer. Documentation of each load recycled is
required for payment.
3.5 SUBSURFACE CONDITIONS
Please refer to Invitation for Bid (IFB) Package Part 2 – Instructions to Bidders Section 18.0
(Subsurface Conditions) for information for Bidders regarding subsurface conditions.
3.6 EXCAVATION
It is the Contractor’s responsibility to fully examine and inspect the project site and documents
pertaining to the physical conditions of the project area, prior to submitting the bid, as further
specified in Instructions to Bidders Section 6.0 (Pre-Bid Investigation). The Contractor shall include
all necessary cost in one or more bid items to perform excavation and complete the work
successfully. It is the Contractor’s responsibility, prior to construction, to contact all outside
agencies or owners if the Contractor becomes aware of any actual or potential discrepancies
between existing field conditions and conditions shown on the project plans. Some utilities may be
identified from the presence of visible facilities, such as building, meters, junction boxes, manholes,
etc. Private irrigation pipes are typically not marked or shown on project plans. The Contractor
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 9
shall anticipate sprinkler/irrigation pipes to be encountered on private properties and near
landscaped median/island/planting strip, The Contractor is responsible to repair in kind if damaged
by the Contractor during the construction project.
The Contractor is required to exercise reasonable care when working around any existing utilities
at no additional cost to the City. If conflicts are found during construction activities, Contractor shall
also contact the responsible agencies or owners to locate their utilities or resolve the issues. The
City is not responsible for any delays or additional costs associated with third party utilities.
A. Trench Excavation (Ref. the City of Palo Alto Public Works Standard Drawings and
Specifications). The bottom of the trench shall be a minimum of 8 inches wider than the outer
diameter of the pipe. The depth of trench shall be at least the minimum depth of cover (30" for
gas main and 36" for 8” water main) plus 4" for pipe bedding plus the outer diameter of the
pipe. The Contractor shall support all existing utilities within the excavation or trench as
required to avoid damage to the existing utilities. A plan for supporting the existing utilities shall
be submitted for approval by the Engineer. The Contractor may not start work prior to approval
of the utility support plan.
For Utilities contracts, the cumulative paved surface area opened at any given time due to
potholing and/or excavations shall not exceed 500 linear feet. Potholes shall be classified as
open until final pavement resurfacing has been completed.
For CIP projects no more than one crew installing mains or services/laterals, unless approved
by the Engineer. Other work such as alignment layout, saw-cutting, potholing, trench plate
grinding, excavating, backfilling/restoration, cleaning, or GPS surveying can be performed
simultaneously.
For Utilities contracts, no excavation shall be left open during nonworking hours. All open
trenches and excavations shall be steel plated with non-skid type steel plates (nominal
Coefficient of Friction shall equal 0.35 as determined by California Test Method 342) or
backfilled and paved with temporary asphalt concrete (cutback) at the end of each workday.
Steel plates shall be shimmed with wooden wedges to prevent rocking and 2” of cutback shall
be used at the edges to provide a smooth transition from the pavement surface to the top of
the plates (one-foot wide minimum ramp with 24:1 slope). Steel plates subject to turning
vehicles or vehicle acceleration and de-acceleration shall be welded together and/or anchored
to prevent movement. Additionally, steel plates shall not have any protrusions above the top
surface of the plate.
Plates shall be checked for proper placement at the end of each work day and
adjusted/leveled/shimmed as required. Steel plating shall be avoided in designated bicycle
lanes by backfilling and in installing temporary pavement at the end of each day. Plating
installed along bike boulevards, arterial roadways, or along roads with a posted speed limit of
35 MPH or greater shall be set flush with the surrounding asphalt concrete surface. Plating
installed in Class II bike lanes or bike boulevards shall be skid resistant and have a reflective
thermoplastic coating for additional safety and shall be set flush with the surrounding asphalt
concrete surface. Additional warning signage shall be posted on Type II flashing barricades All
temporary steel plates shall be removed within 14 calendar days after placement. Refer to the
City of Palo Alto Public Works Standard Drawings and Specifications for additional
requirements.
B. Handling of Pipes and Materials into the Trench. All fittings, valves, hydrant buries, manholes
and pipe lengths shall be carefully lowered into the trench by means of suitable tools and
equipment, in such a manner as to prevent damage to materials. Under no circumstances
shall utility main materials be dropped or dumped onto the work area or into the trench.
Pipe support stands shall be utilized to support pipe during fusion joining, directional boring pull
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 10
in, lining sewer mains, and while lowering of the pipe into the trench. Pipe support stands shall
not be spaced greater than 15' for directional boring pull in and lining sewer mains.
Throughout the duration of the job, the Contractor shall have a crew available to promptly backfill
and repair paving at trench and manhole locations where settlement or cave-ins have occurred.
The Contractor shall make periodic inspections of the trench at least once a week as well as
immediately after rain to repair any defect at once.
Sufficient pumping equipment shall be provided to maintain the bottom of the trench dry during
placement of the pipe bedding and other backfill material. The pump discharge water shall be
pumped into sewer or as otherwise directed by the Engineer. The pump discharge water shall not
be routed to natural drainage channels or storm sewers (Refer to Public Works Department Storm
Water Pollution Prevention policy).
All crossing pipelines shall be protected from damage during excavation by using hand tools or
Hydro-Vac to expose them. All exposed gas lines shall be inspected for wrapping damage by the
WGW Utilities Inspector prior to backfill. It is the Contractor’s responsibility to inform the WGW
Utilities Inspector when gas lines are exposed to facilitate an inspection.
Contractor is responsible for disposal of all excavated soils associated with the project during
construction. It is the Contractor’s responsibility to characterize all excavated soils for disposal by
sampling and testing it in accordance with landfill operation requirements. All samples shall be
taken in the presence of the City Inspector. The City will not pay for disposal of excavated soils that
were not sampled and approved by City Inspector prior to disposal. Once testing has been
completed, it is the Contractor’s responsibility to identify suitable landfill facility, and to transport
and dispose the excavated soils.
3.7 HIGH PRESSURE GAS AND HIGH VOLTAGE ELECTRIC
Extreme caution shall be used when working around PG&E high pressure gas mains and CPA high
voltage electric duct bank.
PG&E’s transmission pipelines can be reviewed in PG&E’s website
https://www.pge.com/en_US/safety/how-the-system-works/natural-gas-system-overview/gas-
transmission-pipeline/gas-transmission-pipelines.page. When potholing or working within 10 feet
of PG&E mains, the Contractor shall reach out tocontact PG&E twenty (when the Notice of Award
is issued20) business days prior to start of work to coordinate and schedule standby inspection.
Hand digging is required within 2 feet (tolerance zone) on either side, of the outermost edge, of the
PG&E mains. The Contractor shall include the cost in one or more bid items and adequate lead
time to comply with PG&E requirements such as obtaining applicable permits, scheduling for
inspection, , locating, hand-excavation, restoration, etc.
When parallel boring or trenching is performed outside of the tolerance zone but within 5 feet of the
outermost edge of the PG&E facility, then pothole the edge of the PG&E facility, at 50 feet intervals,
on the same side of the bore or trench. The Contractor shall contact PG&E to confirm the latest
requirements.
When potholing or working within 10 feet of CPA electric duct bank(s) containing energized 60kV
cables, the Contractor shall notify Utilities Electric Operations at (650) 496-6914 at least five (5)
working days in advance of construction activities to schedule standby inspection. Hand digging is
required within 2 feet on either side of 60kV duct bank. The Contractor shall include the cost in
one or more bid items to comply with all Electric Utility requirements, including but not limited to:
observing the path of the bore-head, supporting thermal sand surrounding 60kV duct bank to
preserve as much of it as possible, hand-excavation, backfilling around 60kV conduits with new
thermal select backfill, restoration, etc.
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 11
3.8 ALIGNMENT AND GRADE CONTROL
The grade and alignment of new pipe shall be maintained by use of laser survey equipment. The
proposed equipment shall be submitted for approval prior to commencing the work. The Engineer,
at any time during the course of the work, may require alterations of the grade control method to
conform to the required conditions of the work.
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 12
3.9 SHORING FOR UTILITIES CONTRACTS
Pursuant to Section 6705 of the California Labor Code, for any contract over $25,000 involving a
trench or trenches five feet or more in depth, the Contractor shall submit a detailed plan showing
design of bracing, sloping or other provisions to be made for worker protection from the hazards of
caving ground. Such plan shall be submitted for acceptance at least five (5) days before the
Contractor intends to begin work on the trenches or shoring pits. If such plan varies from the shoring
system standards established by the Construction Safety Orders, the plan shall be prepared and
signed by a registered civil or structural engineer. Said plan shall be accepted by the Engineer prior
to any excavation.
When shoring is required at locations other than those specified in the bid items, the Contractor
shall, at no additional expense to the City, furnish, put in place, and maintain such sheeting and
bracing as may be required to support the sides of all excavations (whether above or below pipe
grade) and to prevent any movement which could in any way diminish the required trench section,
or otherwise damage or delay the work.
The Contractor shall support all existing utilities within the excavation or trench as required to avoid
damage to the existing utilities. Nothing herein shall be deemed to allow the use of a shoring,
sloping or protective system less effective than that required by the Construction Safety Orders of
the Cal. OSHA.
3.10 GROUNDWATER FLOW CONTROL
It shall be presumed that the presence of groundwater will require dewatering operations.
Contractor shall furnish, install, maintain, and operate all necessary pumping and other equipment
for dewatering all excavations, including well-points or wells containing submersible pumps. At all
times, the Contractor shall have on the project sufficient pumping equipment for immediate use,
including standby pumps for use in case other pumps become inoperable.
Dewatering devices must be adequately filtered to prevent the removal of fines from the soil.
Provide discharge sampling locations for each pump and sample and test groundwater pumped
from dewatering devices daily during the first week and weekly thereafter. The results shall be
transmitted to the Engineer upon receipt of the lab reports. If soil fines are being pumped, revise
dewatering operations to prevent the removal of fines from the soil.
The Contractor shall be responsible for any damage to the underground utilities, roadwork, and/or
adjacent structures caused by the Contractor's negligence or willful misconduct, including any
failure of any part of the Contractor's protective works. After temporary protective works are no
longer required for dewatering purposes, they shall be removed by the Contractor.
If pumping is required on a 24-hour basis, engines shall be equipped in a manner to keep noise to
a minimum. Noise level shall conform to the requirements of the City's noise ordinance as stated
in the City of Palo Alto Municipal Code.
Prevent disposal of sediments from the soils to adjacent lands or waterways by employing whatever
methods are necessary, including settling basins. See latest project drawings and the City’s Public
Works Standards for additional requirements for groundwater treatment and disposal.
3.11 BACKFILL
A. Pipe Bedding
All excavated material shall be removed from the site. It is the Contractor's responsibility to
locate a suitable disposal site for all material removed from the trench. Asphalt concrete and
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 13
Portland cement concrete must be disposed of at an inert solids recycling facility, approved by
the Engineer. Documentation of each load recycled is required for payment. No shoring or
bracing shall remain in the trench after backfilling. No wedging or support of the pipe with wood
or any other type of material other than the pipe bedding material shall be permitted.
1. Soil Stabilization: Pipe bedding shall not be placed on unsuitable material. Any unsuitable
material encountered at the base of a fully excavated trench for the pipes or below the
grades shown for manhole excavation shall be removed as directed by the City Inspector.
The unsuitable material shall be replaced with subgrade stabilization material (Class 3
Permeable Material)) wrapped in geotextile fabric. The Contractor shall remove such
unsuitable material to a minimum depth of 12 inches below the bedding to a maximum of
24 inches below the bedding. Subgrade stabilization material shall be compacted per
requirements of Section 26-1.02B of the latest edition of the Caltrans Standard
Specifications to the satisfaction of the City Inspector. Geotextile fabric shall be Mirafi 600x
or equal. Overlap the seam running along the trench 12 inches minimum; overlap the seam
perpendicular to the trench 24 inches minimum.
Trench bed shall be smooth, uniform, and free of debris, sharp rocks, etc. before adding
the pipe bedding.
2. Pipe Bedding For Wastewater Plastic Pipe Construction: The bedding material shall be
washed, ½" crushed rock from 4" to 6" below the pipe to the spring line of the pipe and
compacted per requirements of Section 68-2.02F(4) of the latest edition of the Caltrans
Standard Specifications.
3. Pipe Bedding For Water and Gas Construction: The bedding material shall be sand
bedding 4" to 6" deep below the pipe compacted to a density of at least 90% of the
maximum density as determined by the California Test Method 216.
After compaction, bell holes (if required) shall be cut in the material so that the pipe, when
laid, will have a uniform bearing under the full length of the barrel. The depth of compacted
select material shall be at a minimum of four (4) inches under the barrel, bell or couplings
of the pipe, and maximum of six (6) inches.
After the pipe has been properly laid in the trench, select material shall be placed on both
sides of the pipe and forced under the haunches of the pipe.
B. Initial and Subsequent Pipe Backfill
Initial backfill shall be placed uniformly on both sides of the pipe and in such a manner as to
avoid damage or movement to the placed pipe. Initial backfill shall be placed to a compacted
depth of 12 inches above the top of the pipe and compacted to 90% of maximum density per
ASTM D-1557. When sand is selected the Contractor may elect to “jet” and provide a location
where excess water can be collected at the low points and removed by pumping. Jetting and
vibration shall be at intervals not to exceed six (6) feet, in accordance with Public Works
Standard Drawing (401).
Subsequent backfill shall be placed in 8 inch lifts or less compacted to 90% of maximum density
per ASTM D-1557, with the final twenty four (24) inches mechanically compacted to 95% of
maximum density per ASTM D-1557.
C. Controlled Density Backfill (CDF)
CDF Backfill shall only be used as approved by the Engineer. A twelve (12) inch sand layer
shall be installed above the gas or water pipe before installation of CDF.
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 14
3.12 COMPACTION TESTING FOR UTILITIES CONTRACTS
Compaction testing will be performed by the City's contract soils laboratory under the general
direction of either the WGW Inspector or the Public Works Inspector. The Contractor shall
cooperate, by adjustment of his operation, in order to permit soils compaction testing on all backfill
materials. The City will pay for the initial compaction test; all subsequent compaction tests required
will be at the Contractor's expense.
One (1) full day advance notice will be required for any soil compaction test request. The City
Inspector will schedule the compaction testing according to the date and time provided by the
Contractor. If the Contractor is unprepared at the scheduled time, the Contractor shall pay for
delaying the soil compaction testing.
All other testing required by the Contract shall be provided at the expense of the Contractor.
3.13 PLAN MODIFICATIONS
Field conditions may necessitate minor revisions to the details shown on the project plans. The
Contractor shall obtain the Engineer's approval of any changes necessary for proper crossing of
existing utilities. The revisions will be directed by the Engineer and will not be the basis for a Change
Order Request unless the revisions necessarily increase the cost or time to perform the work.
3.14 INSPECTION
All work shall be subject to inspection by the appropriate City departments at all times, and as
further specified in the Contract Documents, including the General Conditions. Any work concealed
before it has been inspected by the Engineer shall, at the request of the Engineer, be reopened or
uncovered at the Contractors expense. If deficiencies are found, these deficiencies shall be
corrected at the Contractor's expense. In addition to the payment provisions in Article 9 of the
General Conditions, the Contractor shall meet with the City Inspector at the end of each billing
period to quantify the work performed for each bid item.
The City reserves the right to inspect all materials or equipment during the production,
manufacturing or fabricating process, before shipment, or when delivered to the site.
Neither acceptance of the work, nor final payment, shall relieve the Contractor of the responsibility
for performing the work in accordance with the contract requirements. The Contractor shall remedy
any work not conforming to the contract without expense to the City.
Contractors working on City CIP projects shall pay for the City Inspector’s overtime at 1.5 times the
Council approved inspection rate if work is performed beyond the established construction hours,
unless the overtime work is requested by the City. Construction hours for Utilities CIP projects are
8 AM to 5 PM, Monday through Friday, unless otherwise specified.
Contractors working on private development projects shall pay all inspection costs including the
City’s WGW Utility Inspector’s overtime at 1.5 times the Council approved inspection rate for
inspections scheduled outside the hours of 8:00 AM to 3:00 PM Monday through Thursday
excluding City holidays.
3.15 LICENSES, PERMITS AND FEES
The Contractor shall apply, procure, and pay for all licenses and permits, including but not limited
to CPA street-work permit, encroachments permits (including but not limited to the following
agencies: Caltrans, VWD, SFPUC, Caltrain, Santa Clara County, PG&E, Stanford, VTA, and etc.),
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 15
water use, electricity, building permit, noise exception permit, storage of materials, office trailer,
erection of construction shack, etc. required by the City or other government jurisdictions or
agencies. The City will pay for other agency’s inspection fees, unless the fees are related to
damage caused by the Contractor.
The Contractor is responsible for obtaining, at its sole expense, any licenses required by the
contract documents, including the Special Provisions in the Invitation for Bid package. Prior to
submitting the bid, the Contractor shall conduct research of each agency’s specific requirements
to perform work within the agency’s right-of-way or near the agency’s utility; Contractor’s bid will be
deemed to include sufficient costs in the bid to comply with all applicable permit requirements. The
Contractor shall include all associated costs and anticipate potential long lead time to comply with
each agency’s requirements. The Contractor shall provide the City with copies of permits and
licenses.
For any work in railroad’s right of way, the Contractor shall pay for the costs incurred by the railroad
company such as inspectors’ wages, safety flagman’s wages, safety training, and rail supports if
necessary.
Contractor’s bid is deemed to include all costs and expenses for such licenses and permits. No
other compensation shall be paid to the Contractor for these items or for delays caused by non-
City inspectors or conditions set forth in the licenses or permits issued by other agencies.
3.16 PROTECTION OF TREES, PROPERTY, AND SERVICE STRUCTURES
Trees, shrubbery, fences, poles and other property and service structures shall be protected,
unless their removal is shown on the drawings or authorized by the Engineer. Trees shall be
protected per the City of Palo Alto Tree Protection Manual.
Where the City (street) trees obstruct the Contractor's equipment, the Contractor shall be
responsible for all trimming necessary to create clearance for his or her operations. Trimming shall
be done by a certified tree worker or a qualified tree care specialist in accordance with the City of
Palo Alto Public Works Standard Drawings and Specifications. The City Arborist shall be notified
in advance of all branch and tree roots greater than 2 inches in diameter which need to be trimmed
or removed. The trimming or removal of these limbs or tree roots shall be approved by the Arborist
prior to removing.
When performing boring operation below a tree with a tap root, the minimum depth of boring shall
be 5' below the ground elevation.
The Contractor will be assessed charges for any damage to City trees including, but not limited to,
broken limbs and damaged trunks. Charges will be determined by the City Arborist. Any damage
to private trees including, but not limited to, broken limbs and damaged trunks shall be remedied
to the homeowners’ satisfaction.
3.17 ASPHALT CONCRETE PAVING
Place asphalt concrete in accordance with the City of Palo Alto Public Works Standard Drawings
and Specifications, and Caltrans Standard Specifications. Section 17 (Boring, Trenching and
Potholing) of the Public Works Standard Drawings and Specifications lists the requirements for
street restoration for both open cut and directional drilling/pipe-bursting installation in streets,
restoration for both improved and unimproved areas, and required limits of trench restoration. The
minimum pavement section restored shall be two (2) inches asphaltic concrete on eight (8) inches
of Class 2 aggregate base, or the existing pavement and base section, whichever is greater. Class
II aggregate base shall be compacted to 95% compaction.
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 16
Prior to asphaltic concrete pavement installation, all debris (leaves, twigs, trash, etc.) laying on the
top of the compacted trench shall be removed and paint binder (RS-1) shall be applied to all vertical
edges of the surrounding pavement around the perimeter of the trench at a rate of 0.05 to 0.10
gallons per sq. yd. Do not commence placement of asphaltic concrete materials when the
atmospheric temperature is below 50o F, or during fog, rain, or other unsuitable conditions.
The new asphalt concrete shall be placed to the same grade as the surrounding asphalt concrete
grade, such that the originally designated cross-sectional geometry of the road is maintained.
Excess asphalt shall be removed from the working area and not rolled into the mat. Asphaltic
concrete shall be placed with an asphaltic paving machine. A paving box may be used only with
the approval of the Engineer. A maximum of a 3 inch lift is allowed for asphalt concrete pavement.
Final lift of asphalt for trench restoration shall be 3/8" fine.
Upon completion of all asphalt paving, a seal coat (fog seal or sand seal) shall be applied to all
restored surfaces. On streets with slurry seals, the restored trench shall receive a slurry seal coat
in accordance with Section 37-2 of the California Specifications.
Unless otherwise authorized by the Engineer, all construction and restoration shall be completed
within fifteen (15) working days from start of work at any specific location, and final surface
restoration shall be completed within ten (10) working days from the last day pipe was installed on
any particular continuous section. No more than 1,000 feet of temporary pavement will be allowed
before the contractor must install permanent paving prior to proceeding with new trenching
operations.
3.18 PCC PAVEMENT, CURBS, GUTTERS, SIDEWALKS, AND DRIVEWAYS
Place Portland cement concrete and PCC pavement in accordance with the Public Works Standard
Drawings and Specifications, and Caltrans Standard Specifications.
The PCC plug shall be placed to the same grade as the surrounding PCC pavement grade, such
that the originally designated geometry of the roadway is maintained. Excess concrete shall
immediately be removed from the working area and disposed of properly. After placing, the
concrete shall be consolidated sufficiently to produce a dense mass, struck off and floated.
All concrete shall be placed against existing sawcut concrete or 2" thick wood forms. If a gutter
exists, twelve inches of AC will have to be removed at the lip of gutter for the placement of these
forms. No concrete shall be placed against asphalt or spalled/broken concrete.
Forms shall be checked by the WGW Utilities Inspector and Public Works Inspector before any
pouring of concrete. PCC shall not be poured when air temperature is below 40 Deg. F or during
rain or within two hours before sunset. No on-site mixing of PCC shall be allowed.
All new PCC (at sidewalks, curb and gutter, and concrete roads) shall be doweled into existing
PCC using #4 rebar 12" long dowels spaced at a maximum of 2' centers. Dowel holes shall be
drilled in the vertical section center. Dowel holes shall be drilled 6" into the existing concrete without
causing damage. Dowels shall be epoxied into the existing concrete.
Concrete shall be placed and compacted in forms without segregation. After placing, the concrete
shall be consolidated sufficiently to produce a dense mass, struck off and floated. Final finishing
operations shall not proceed until all bleed water has evaporated from the surface. Sprinkling of
dry cement to absorb excessive surface moisture shall not be allowed. The surface texture of
finished concrete shall conform to adjacent concrete. Forms shall not be removed less than twenty-
four hours after the concrete has been placed. In no event shall forms be removed while the
concrete is sufficiently plastic to slump.
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 17
If any portion of sidewalk is sawcut or damaged during the course of work, the Contractor will be
required to remove and replace the entire width of sidewalk from the planting strip or property line
edge of the walk to the curb edge between the nearest undamaged joints.
As soon as the concrete is set, it shall be cured for a period of at least 72 hours by spraying with
an approved pigmented impervious membrane-curing compound.
The Contractor shall protect from damage all completed Work. All discolored concrete shall be
cleaned to a uniform color. Repairs and cleaning of new concrete shall be at the expense of the
Contractor.
3.19 PAVEMENT STRIPING AND LEGENDS
Contractor shall replace all pavement striping, legends, signs, and curb painting damaged due to
the Contractor’s activities in kind unless a redesign is ordered by the Engineer. Place pavement
striping, legends, signs, and curb painting in accordance with the Public Works Standard Drawings
and Specifications, and Caltrans Standard Specifications.
Temporary traffic striping and legends shall be placed on the newly paved street prior to the release
of the street to the public. These materials shall be either pop-up temporary markers (for arterial
streets) or tape (for residential streets). The proposed materials must be submitted to the Engineer
for approval prior to use. Permanent striping must be installed within seven (7) days.
Alignment lines shall be established by the application of cat tracks or dribble lines, the use of laser
guidance devices or a combination of both, as detailed in the Caltrans Standard Specifications.
Pavement markers and Stimsonite fire hydrant markers shall be placed in accordance with the
Caltrans Standard Specifications and manufacturer's installation procedures.
Tape striping, legends, signs, markings, or other facilities removed or damaged during construction
shall be repaired or replaced in kind at no expense to the City within ten (10) working days of the
last day pipe was installed on any given continuous section.
All materials, equipment and labor required to perform surface restorations shall be included in one
or more of the bid items and no further compensation will be allowed for surface restoration.
Thermoplastic material and paint for traffic stripes and pavement markings shall be applied in
accordance with the California Standard Specifications, Section 84, and manufacturer's installation
procedures.
Tape shall be applied using a mechanical applicator furnished by the tape vendor. Installation shall
be in accordance with the manufacturer's recommended installation procedures.
3.20 TRAFFIC LOOPS
In the event the Contractor severs any part of a traffic loop, the Contractor is responsible for
replacing the entire traffic loop at the Contractor's expense, in accordance with the following
standards:
A. The Contractor shall replace the affected loop within 72 hours following the completion of the
surface restoration on the affected street. If this replacement is not done by this deadline, this
work will be done by the City at the Contractor's expense.
B. The Contractor shall coordinate all signal loop work with the City Traffic Signal Division.
EXCAVATION, BACKFILL, AND RESTORATION SECTION 2200
CITY OF PALO ALTO Section 2200 PAGE 18
C. Loops shall conform to City of Palo Alto wiring diagram quadrupole detector loops, Drawing K-
1184. Each loop shall be identified in the pull box as to location, I.E. "2WR" or "2WL".
D. No separate bid item is made for the cost of replacing or repairing any traffic loop. It is the
contractor’s responsibility to determine the expense of potential damage to traffic loops and
include cost in the bid items.
E. Diagrams for City owned traffic detection loops are available from the City of Palo Alto
Transportation Division of the Planning Department. For non-City owned traffic detector loops,
contact the appropriate agencies (Caltrans, Santa Clara County, etc.)
3.21 LANDSCAPING AND MISCELLANEOUS
All monuments within the project site shall be preserved as required by the State and local
regulations. Damaged or destroyed monuments shall be replaced by a California licensed Land
Surveyor hired by the Contractor. The Contractor shall submit the method and procedures of tying
out the monuments for the City Surveyor’s approval. The Contractor shall also provide a recorded
copy of the “corner record” to the City Surveyor. No separate bid item was made for the cost of any
surveying or monument replacement work. The cost shall be included in one or more of the bid
items.
The Contractor shall restore any special surface treatments encountered in the execution of this
Work to an equivalent or better condition than existed prior to the commencement of this Work.
After each site has been completed, the Contractor shall restore landscaping and areas abutting
the work to the condition existing at the start of work. All materials, equipment and labor required
to perform surface restorations shall be included in one or more of the bid items and no further
compensation will be allowed for surface restoration.
END OF SECTION
POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 1
SECTION 2300
POLYETHYLENE PIPE INSTALLATION
FOR WATER, GAS AND WASTEWATER
PART 1 – GENERAL
1.01 DESCRIPTION
Work includes fusion and installation of 1” and greater medium and high density polyethylene
services and mains, all appurtenances and all related equipment and fittings in accordance with the
requirements of the Contract Documents.
1.02 RELATED WORK
A. Section 2200: Excavation, Backfill and Restoration
B. Section 2660: Water Design and Construction Standards
C. Section 2685: Natural Gas Distribution System
D. Section 2735: Polyethylene Sewer Pipe
E. Section 2737: Sanitary Sewer Lateral
1.03 POLYETHYLENE PIPE
A. Gas: 2708 medium density polyethylene (MDPE), uniformly yellow in color. Pipe wall thickness
shall be 0.099” minimum for 1” CTS, SDR 11 for 2” IPS pipe, and SDR 11.5 for 3” through 8” IPS
pipe. Refer to Section 2685 of these Standards for additional requirements. 1” CTS and 2” IPS
pipe shall be supplied in coils. The coils shall be furnished in either 500 or 1,000-foot lengths
specified at the time of order (2” straight 20’ or 40’ lengths can be used for shorter services and
connections).
B. Water: 4710 high density polyethylene (HDPE). Pipe wall thickness shall be SDR 9 for 2” IPS
pipe and SDR 11 for 4” and greater IPS pipe. All water main pipes shall be black with four (4)
longitudinal blue single stripes evenly spaced. Solid blue pipe may be acceptable if the pipe
meets Standard Specifications Section 2660 and with prior approval. Refer to Section 2660 of
these Standards for additional requirements. 2” IPS pipe (water services) shall be supplied in
straight lengths only.
C. Wastewater: 4710 high density polyethylene (HDPE). All wastewater main pipes shall have
white, grey, or light-colored interior. The exterior color can be black or grey with four (4)
longitudinal green single stripes evenly spaced. Solid green exterior color is acceptable if the
pipe meets Standard Specifications Section 2735 and with prior approval. Pipe wall thickness
shall be SDR 17. Refer to Section 2735 of these Standards for additional requirements.
Pipe 4” IPS through 18” IPS shall be supplied in 40 foot or longer straight lengths. Straight lengths
shall consist of a single length of pipe without couplings or any intermediate joints.
Pipe markings shall be in a color that contrasts with that of the pipe and space at intervals not
exceeding two (2) feet. All required markings shall be legible and so applied as to remain legible
under normal handling and installation practices. These markings shall consist of the Utility (GAS,
WATER or SEWER), the designation (ASTM D2513 (gas), cell classification confirming to the latest
ASTM D3350 234373E (gas), 445574C (water), indicate listing under ANSI/AWWA C906 (water),
the manufacturer's name or trademark, the nominal pipe or tubing size (including the sizing system
used, such as, IPS, CTS or OD), the type of material, SDR number, the month and year of
POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 2
manufacture, and identification of resin supplier (if other than pipe manufacturer), and manufacturer
(P for Performance Pipe, or I for Ineos, etc.).
All pipe shall be made of virgin quality material and be homogeneous throughout and free of visible
cracks, holes, foreign inclusions, blisters, dents, and other injurious defects. No reworked material
shall be allowed. The pipe shall be as uniform as commercially practicable in color, opacity, density,
and other physical properties.
Black polyethylene water pipe, yellow polyethylene gas pipe, and black or grey polyethylene sewer
pipe (inner wall shall be white or light in color) shall be no older than six (6) months from the date of
manufacture to the date of arrival to CPA. All pipes shall be packaged in standard commercial coils
or bundles that provide protection from shipping injuries and shipped with pipe caps. When storing
the pipe on site, the Contractor shall protect pipe from direct sunlight by UV resistant cover. All pipe
must be installed within 3 years of the manufactured date.
1.04 POLYETHYLENE FITTINGS
All polyethylene fittings shall have butt end outlets. Molded and fabricated fittings shall have a
pressure rating equal to the pipe. Minimum pipe wall thickness for fitting butt outlets shall be equal to
the pipe wall thickness.
All fittings shall be made of virgin quality material and be homogeneous throughout and free of visible
cracks, holes, foreign inclusions, blisters, dents, and other injurious defects. No reworked material
shall be allowed. The fittings shall be as uniform as commercially practicable in color, opacity,
density, and other physical properties.
Fittings shall be molded, except fittings larger than 12”, which are allowed to be factory fabricated
(unless molded fittings are available). Fabricated fittings shall be fabricated on machinery specifically
manufactured for that purpose. Fabricated fittings shall be manufactured using Data Loggers
recording heating iron face temperatures, fusion pressure and a graphic representation of the fusion
cycle. The Data Logger printout shall be part of the required submittal for the fabricated fitting.
Fabricated fittings shall be manufactured by ISCO or approved equal. All fabricated fittings must be
approved by the Engineer prior to installation.
Gas fitting marking shall be in compliance with ASTM F2897-14 Standard Specification for Tracking
and Traceability Encoding System of Natural Gas Distribution Components (Pipe, Tubing, Fittings,
Valves, and Appurtenances) and consist of 16-digit alpha-numeric code and scannable code 128
barcode, or QR code, which standardizes encoding of pipe specifications as described in the
referenced Standard.
In addition to the compliance with the requirements of ASTM F2897-14, gas fitting markings shall
also comply with the marking requirements for all polyethylene fittings specified in this Section as
stated below.
Fittings shall be marked with the following: ASTM D3261 (Butt type); manufacturer's name or
trademark; material designation; date of manufacture or manufacturing code; size (including the
sizing system used, such as, IPS, CTS or OD). Where the fitting size does not allow complete
marking, marking may be omitted in the following sequence: size, date of manufacture, material
designation, and manufacturer's name or trademark.
PART 2 – MATERIALS AND INSTALLATION
2.01 POLYETHYLENE PIPE JOINING EQUIPMENT
POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 3
All polyethylene pipe joining equipment to be used shall be certified by the City of Palo Alto to be in
good working condition and suitable for the intended purpose prior to being brought on site. Any
equipment without a City issued certification tag shall be removed from the site. The Contractor shall
have all equipment necessary to install the pipe and appurtenances referred to in the Plans and
Specifications, including but not limited to:
A. Pipe Trailer: Contractor shall provide a trailer capable of transporting 40' or longer lengths of
polyethylene pipe without damaging pipe.
B. Pipe Spool: Contractor shall provide a reel type spooling device capable of dispensing 500' long
2" polyethylene pipe coils. Spool can be trailer mounted or suspended from a truck or backhoe
(SpeedReel).
C. Pipe Support Stands: Pipe support stands shall be utilized to support pipe during fusion joining,
directional boring pull in, and while lowering of the pipe into the trench. Pipe support stands shall
not be spaced greater than 15' apart for directional boring pull in. Pipe shall be supported with
stands at all times and not placed on pavement to avoid scratching the pipe surface.
Additionally, manufactured pipe support stands outfitted with rollers shall be used at the
pavement or plate edge where pipe is pulled into the trench/bore hole to avoid scratching of the
pipe.
D. Pipe Cutter: Pipe cutter for polyethylene pipe shall be:
x For 2” – 12” diameter pipe guillotine style pipe cutter outfitted with a ratchet drive or power
driven designed to cut medium/ high density polyethylene pipe. For 6”-12” diameter pipe
PLAS In-line Rotary cutters manufactured by Reed Pipe Tools & Vises
(www.reedmfgco.com), or approved equal.
x For pipe larger than 12” PLAS In-line Rotary cutters manufactured by Reed Pipe Tools &
Vises (www.reedmfgco.com), or approved equal.
No other cutting tools will be allowed unless approved by the Engineer.
E. Butt Fusion Machine: Contractor shall provide McElroy or approved equal butt fusion
machine(s) capable of fusing the range of pipe sizes required in the contract/plans with the
following features:
1. Butt Fusion Machine: Machine shall be the hydraulic fusion machine with built-in hydraulic
pipe lift to assist with the pipe handling and incorporating centerline guidance system and
DataLoggerTM compatible, and capable of butt fusion of most fittings without special holders
or removal of jaw.
2. Facer: Pipe facer that attaches to the butt fusion machine. Facer shall have sharp properly
aligned blades.
3. Heating Iron: Electrically powered heating iron with unscratched clean Teflon coated faces.
Heating iron shall have a thermometer and temperature set screw for calibration.
F. Electrofusion Machine: The Contractor shall provide a Friatec universal electro fusion control
box or approved equal, capable of storing a minimum of 100 fusion records, pipe alignment
POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 4
clamp, tapping tee alignment clamp, tapping wrench, pipe scraper, and all other tooling specified
by the electro fusion machine manufacturer installation procedures.
G. Electric Generator: Contractor shall provide the necessary power supply to meet the power
requirements as specified by the manufacturer of the fusion equipment. Generator shall be in
new condition and have a minimum rated capacity of 5 kW for 8” and smaller and 10 KW for 10”
and larger.
H. Pyrometer: The Contractor shall provide a pyrometer capable of testing the temperature of the
heating iron, while at fusion temperature, to an accuracy of 0.5% (r3qF). The fusion temperature
of the heating iron shall be verified each morning in the presence of the WGW Inspector. More
frequent testing may be required at the discretion of WGW Inspector.
Note: The Contractor shall keep a binder on site containing the fusion procedures, names of
approved fusers and serial numbers of the approved fusion equipment. All equipment must be in
good working order and properly maintained during project installation. The City will inspect the
preceding items and reject those not in compliance. The City shall have the right to reject any or
all equipment judged inadequate to properly fuse polyethylene pipe and its fittings.
2.02 POLYETHYLENE PIPE INSTALLATION PARAMETERS
The City will test to qualify all person(s) intending to make polyethylene joints by fusion. The persons
will be allowed to perform fusion only for the utility (water, gas or wastewater) they were qualified.
The fusers must be requalified at the start of any new project, regardless of whether or not the fuser
was certified previously on another project. A minimum of two certified fusers shall be on-site at all
times during fusing operations and all fusions must be conducted in the presence of or with the prior
approval of the City's WGW Inspector.
Applicants for testing will need to demonstrate a working knowledge of PE fusion and equipment
without any guidance, including setting up the equipment, verifying the proper settings, and
completing a test fusion sample. All testing procedures are based on the ASTM F2620 current
revision standard. Applicants will have one opportunity to pass the test per day. If the test is failed,
another test will not be administered for a minimum of 5 days.
At the Contractor’s expense, the Contractor’s employees who perform fusion on the projects will be
required to attend a fusion class conducted by a certified pipe or equipment manufacturer. Proof of
attendance will be required when scheduling fusion testing with the City-authorized testing company
or personnel. If construction is expected to last more than one year, the Contractor’s employees who
perform fusion will also be required to attend annual fusion training classes. Proof of attendance shall
be submitted to the Engineer within one year of the original certification date. See Section 2400
(HDPE Water and Sewer Pipe – Fusion Training Procedures and Certification) and Section 2500
(Polyethylene Gas Pipe Fusion Training Procedures and Certification) for additional testing
requirements.
The Contractor’s employees will perform the qualification testing at the yard of City-authorized testing
location. The Contractor shall bring his own equipment and materials to be used on the project for
testing (including but not limited to generator, fusion machines, scrapers, etc.). The Contractor will be
required to schedule fusion testing four (4) weeks prior to the start of Work. The Contractor shall
coordinate testing schedule with City-authorized testing company or personnel and provide them with
two (2) weeks advance notice.
The City will test the Contractor’s fusers once at no cost to the Contractor. Contractor shall send all
POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 5
potential fusers for the project to the test at the same time. If any of Contractor’s fuser fails to pass
the first qualification test, the City may charge the Contractor for time spent retesting each fuser. The
Contractor is responsible for any delays in meeting Contract requirements that is attributed to
retesting of the Contractor’s fusers. No additional contract days, or monies, will be given due to
retesting.
A. Underground Clearance: Unless otherwise specified on the Project Drawings or approved by
CPA Utilities Engineering, the Contractor shall maintainproposed pipe shall have at least 18”
vertical clearance to crossing sewer mains, a minimum clear separation of 12” vertical clearance
(outside wall to outside wall of fittings/pipe/structure) ly to other crossing utility lines or structure,
and 48” horizontal clearance ly to parallel utility lines, duct banks or adjacent foreign structures.
The clearance should be measured from outside wall to outside wall of fittings/pipe/structure. ,
except iIn the case of new water construction, . Tthe distance separation between new water
mains and existing sewer lines mains shall be at least 10-feet horizontally and 1-foot vertically
per Regional Water Quality Control Board (RWQCB) requirements. If the 10-feet horizontal or 1-
foot vertical clearances are not attainable, the RWQCB will need to review and approve the
plans. For all other utilities, if horizontal separation is less than 4’, review and approval by CPA
Utilities Engineering is required.
B. LocationConfiguration: Contractor shall install mains and services as follows:
1. Mains and services shall be located configured per WGW Utilities standard drawing WGW-
01, unless otherwise specified on the Project Drawings.
2. Services shall be installed perpendicular from the main in the shortest straight line to the
meter or clean out, if possible. Water meters, services and sewer laterals shall be installed
10' minimum from trees, if possible.
Handling of Polyethylene Pipe: Extreme care must be exercised when moving plastic pipe.
POLYETHYLENE PIPE SHALL NOT BE DRAGGED ON THE GROUND OR ON PAVED
SURFACES. Support stands and rollers must always be used to keep the pipe above paved
surfaces/ground level, including but not limited to fusing, transporting, lowering pipe into the
trench or bore hole, during directional boring pull-in or pipe-bursting operations, etc.
C. Pipe Scratches or Cuts: Pipe that has scratches, notches, cuts or any other abrasions that
exceed ten percent (10%) of the gas/water pipe wall thickness, or 20 percent (20%) of the sewer
pipe wall thickness, shall be disposed of. The Contractor is responsible for the cost to replace
damaged pipe. The Contractor shall use pipe stands, rollers, spooling devices, or other means
to avoid damaging the pipe during installation. Observe pipe during installation for scratches,
gouges or other defects. If defects are present, remove and discard defective sections of pipe.
The WGW Inspector must be notified of all defects and subsequent repairs. The Contractor is
responsible for the cost to replace damaged pipe if it is a result of not using stands, rollers,
spooling devices, or other means to protect the pipe during installation.
D. Pipe Squeeze Off Tools: Manual squeeze off tools can be used for pipelines with diameter of
½”CTS – 2”IPS. Hydraulic squeeze off tools are necessary for pipelines with diameter of 3”IPS –
8”IPS. These tools should be equipped with stops for each size to prevent over squeezing of the
pipe.
E. Snaking Pipe: Polyethylene pipe shall be installed in the trench by “snaking” method and
additional pipe length shall be allowed for the possible thermal contraction of the pipe.
POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 6
F. Maximum Pull Force: A commercially available weak link approved by the Engineer for the
specific application shall be used, in accordance with manufacturer’s recommendations, between
the puller and the pipe, for water and gas construction. See Section 2.03.A.4 for maximum pull
forces.
G. Butt Fusions: All butt fusions shall be performed by the Contractor as follows:
1. All butt fusions must be performed by the person(s) qualified and certified by the City to butt
fuse in the presence of the City's WGW Inspector. Fusion qualified Contract employees
found to not be following manufacturer’s guidelines or performing fusions with inadequate or
defective equipment will have their fusion qualifications revoked and will not be allowed to
perform fusions for the remaining duration of the contract.
2. Pipe fusion shall be conducted in accordance with the manufacturer’s recommended fusion
procedure and in compliance with the most current version of ASTM F2620, PPI Technical
Report TR-33, and in accordance with the "City of Palo Alto, Polyethylene Pipe Fusion
Training Procedures". See Sections 2400 and 2500 of the City of Palo Alto Water, Gas, &
Wastewater Utility Standards.
3. Ambient temperature shall be between 55° F and 85° F prior to pipe fusion; otherwise pipe
shall be protected from direct sunlight and cooled down until the ambient temperature falls
within the above temperature range.
4. Fusion joints shall be allowed to cool for the times recommended by the pipe manufacturer
prior to any movement of the fused joint.
5. All non-manual fusions shall be made using a Data Logger recording heating iron face
temperatures, fusion pressure and a graphic representation of the fusion cycle. The Data
Logger data shall be reviewed by Inspector prior to pipe being pulled in. Data Logger
records shall be uploaded daily to a cloud server for remote viewing from any location.
H. Inspection: The following is a list of inspection duties both required of the City and Contractor:
1. The City will provide a polyethylene certified Inspector at the job site. The Inspector has the
right to reject any fusions not meeting City requirements. The Contractor shall replace all
fusions not meeting City requirements at its own expense.
2. In addition to the City certified fusers, the Contractor shall also provide a City certified
polyethylene fusion supervisor who will be present on site at all times to inspect, guide,
advise, ensure that all required procedures are adhered to, to witness the quality of each
joint, and to observe pipe fuser(s) as they work. The Contractor’s supervisor will be
responsible for inspecting all fusions performed. As with the City certified fuser, the fusion
supervisor will be tested and qualified by the City.
3. At the City's discretion the Contractor will remove fusion(s) and supply it to the City for
testing to ensure quality control.
4. Fusion records shall be downloaded and provided to the City in electronic format on a weekly
basis. Records of all non-manual butt fusions shall be uploaded daily to the cloud server.
The City may require paper record copies on a weekly basis.
Records of all non-manual butt fusions shall be uploaded daily by the Contractor to the cloud
POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 7
server, in a sub-account to be created by the City for the Contractor, under the City’s
account. City will provide Contractor login info. The City may require paper record copies of
manual fusions.
5. Any failure recorded by the fusion equipment must be immediately brought to the attention of
City’s Inspector to avoid the City requiring the contractor to remove fusions to the last
recorded acceptable fusion.
6. The fusion number corresponding to each joint shall be written on the pipe at the fusion
location with an indelible marker.
7. Fusion number(s) shall also be noted on the Contractor’s record drawing at the approximate
location(s) of the fusion for both water and gas installation.
8. The City’s Inspector will observe plastic fusions and reject all connections which are
deficient. All fusions must be conducted in the presence of or with the prior approval of the
City's WGW Inspector. The City’s Inspector will review the Data Logger or non-destructively
test plastic fusions and reject all connections that are deficient. The contractor will replace all
fusions failing non-destructive testing at his expense. The contractor will replace all fusions
failing visual inspection or non-destructive testing at his expense.
I. Sealing Installed Piping: Contractor shall seal open all water and gas piping with butt fusion
end caps at the end of each workday. No open pipe ends (or ends sealed with tape) will be
allowed at the end of the day.
J. Minimum Bending Radius: The minimum bend radius for polyethylene water pipe SDR 9 is
twenty (20) times the outside pipe diameter, for SDR 11 is twenty five (25) times the outside pipe
diameter, and for SDR 17 is twenty seven (27) times the outside pipe diameter. If fusions, fitting,
or flange are present or to be installed in the bend, the minimum bend radius shall be one
hundred (100) times the outer pipe diameter.
2.03 POLYETHYLENE PIPE INSTALLATION METHODS
A. BORING
The Contractor shall not change the installation method from direction boring or pipe bursting to
open trench without the Engineer’s approval. See WGW Utility Standards Section 2735 for
sanitary sewer projects.
The pilot bore for utility mains and services shall be a minimum of 24" clear from other
underground facilities. The Contractor shall install pipe by directional boring method only when a
minimum of 24” separation is achieved, unless otherwise approved by the Engineer.
1. Boring Machine
The contractor shall provide a utility line boring machine(s) capable of installing 1" thru 8" pipe by
directional boring.
a. Service Line Boring Machine: The contractor shall provide a boring machine or pneumatic
gopher capable of installing 1", 1-1/2", and 2" pipe.
POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 8
b. Directional Boring Machine. The Contractor shall provide a directional boring machine
capable of drilling a pilot hole along a predetermined path to a specified target location, then
enlarge the pilot hole to desired size while pulling in specified size pipe. The boring machine
shall be equipped with mechanical and hydraulic deviation equipment capable of changing
the direction of pilot drilling course. The boring machine shall also include a fluid
mixing/pumping system capable of lubricating the bore hole with drilling fluid to insure
complete consolidation of the soil after pipe installation and to minimize friction forces during
pull back.
c. Locating System. The Contractor shall provide a locating system able to monitor the location
and orientation of the drilling head assembly along a predetermined course. The locating
system shall be capable of locating the drill head both horizontally and vertically to an
accuracy of ± 1" at 10' depth, and detect the rotation angle of the head.
d. Compaction/Reaming Devices Management. The Contractor shall be responsible for
selection of the method(s) of expansion of a pilot hole, if required, and assume full and sole
responsibility for location and protection of the existing underground facilities as specified in
Subpart 3.08 of this specification.
e. Maximum diameter of the pilot drill bit shall not exceed 3.5 inches in diameter, unless
approved by the Engineer.
2. Directional Boring Method
a. Drill a pilot hole with fluid assisted mechanical cutting head along a predetermined path to a
specified target location. Drilling fluid can be a mixture of water and bentonite, polymers, or
other approved additives. No fluid shall be discharged into the streets, gutters, or sewers.
Fluid pressure and flow rate shall be minimized through the use of relief holes during the
drilling operation to prevent fracturing the subgrade material around and above the pilot hole.
Uncontrolled jetting is prohibited. Any fluid discharged onto streets, sidewalks or customer
property, shall be properly disposed of including cleaning of the affected area. Excess drilling
fluid must be removed from the surface of relief holes prior to paving.
b. Enlarge pilot hole with cutters or reamers to desired size and pull in specified size pipe while
injecting fluid mixtures to hold reamed hole open and lubricate the utility line being pulled.
Reamer sizes are listed below.
Pipe size
(in.)
Minimum Reamer Size
(in.)
2 4
4 8
6 12
8 14
10 and 12 18
>12 >50% of pipe diameter and approved by the Engineer
A commercially available weak link approved by the Engineer shall be used between the
puller and the pipe, in accordance with manufacturer’s recommendations, no matter the
material or size of the pipeline being pulled.
POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 9
c. The Contractor will be allowed to leave drill rods in the ground overnight, however pipe
pulling must be completed on the same day as it is initiated. Prior to pipe pulling, an end cap
and tracer wire must be attached.
d. The Contractor is required to protect pipe from scratching and gouging on edges of trench,
plates or pavement during pull in. Rollers shall be used at all bend points in the launching pit
and every 15’ along the pipe. Methods of protection shall be submitted for review and
approved by the Engineer prior to performing the Work. Dragging of the pipe on paved
surfaces is not allowed.
e. After the pipe is pulled in, verify the lead edge of pipe is free of gouges greater than 10% of
the pipe wall thickness. Check continuity of tracer wire to ensure tracer wire remained intact
during pull in.
f. Pressure test pipe with air or water per the respective utility.
3. Bore and Jack
At railroad and major street crossings where open excavation cannot be made, a steel
casing shall be installed by boring and jacking after permitting and coordinating with agency
having jurisdiction. The grade shall be as shown on the Plan and Profile drawings and the
casing shall be installed to permit the carrier pipe to be spaced as shown in the drawings.
The size of the casing shall be as specified in the Drawings and Specifications. Link Seals
or approved equal, shall be installed at both ends of the casing and manufactured casing
insulators shall be installed at 5 foot maximum intervals on the carrier pipe prior to insertion
as shown on the project drawings.
Joints between sections of the casing shall be welded for the entire circumference of each
joint. This weld shall be a minimum of two complete passes.
The contractor shall furnish casing for locations shown on the Plan and Profile drawings. If
for convenience of construction, the contractor should select to install casings at locations
other than those shown on the Plan and Profile drawings, he or she may do so at his/her
expense provided the Engineer approves and required permits allow installation at the new
locations.
Note: All equipment must be in good working order and properly maintained during project
installation. The City will inspect the preceding items and reject those not in compliance. The
City shall have the right to reject any or all equipment judged inadequate.
4. Maximum Pull Force
The allowable tensile load is calculated based on fY = 0.40; fT = 1 hour; TY @ 100 qF. Refer
to Section 2300.1.03 for SDRs for each type of pipe.
i. MDPE 2406 (gas pipe):
Pipe size
(in.)
Maximum Allowable Pull Force
(lb.)
POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 10
1 300
2 1,600
4 4,640
6 10,060
8 17,060
ii. HDPE 4710 (water or gas* pipe):
Pipe size
(in.)
Maximum Allowable Pull Force
(lb.)
2 2,020
4 6,090
6 13,210
8 22,390
10 34,780
12 48,930
14 59,000
16 77,060
18 97,530
*HDPE gas pipe shall only be used for special cases upon Engineer’s request and approval.
iii HDPE 4710 (sewer pipe):
Pipe size
(in.)
Maximum Allowable Pull Force
(lb.)
4 4,080
6 8,850
8 15,000
10 23,300
12 32,780
14 39,520
16 51,620
18 65,330
20 80,660
iv Steel Pipe pull forces shall be approved by the Engineer prior to pulling.
B. DIRECT BURIAL
1. Excavate to the required depth and ensure trench bottom is level and free of sharp objects,
rocks, or other materials that may damage pipe. Shade excavation with 4” to 6” sand or ½”
crushed rock bed and level sand or crushed rock as needed. Refer to Utility Standard Detail
WGW-02 for bedding requirements.
2. Install pipe in excavation, with #10 tracer wire on top, and snake pipe. Observe pipe during
installation for scratches, gouges, or other defects. Avoid dragging pipe over rough surfaces.
3. Backfill to top of pipe with sand or ½” crushed rock and haunch the sides. Continue
backfilling pipe with sand or ½” crushed rock to 12” above top of pipe and install warning
tape. Backfill remaining excavation in 12” lifts and compact to 95% compaction.
POLYETHYLENE PIPE INSTALLATION SECTION 2300
CITY OF PALO ALTO Section 2300 PAGE 11
END OF SECTION
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 1
SECTION 2400
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER)
7/19/21
TABLE OF CONTENTS
PAGE
SUBJECT NUMBER
Heat Fusion Tools 2
Manual Butt Fusion Procedure (City Staff Only) 4
Hydraulic Butt Fusion Procedure 7
Electro Fusion Procedure 7
Requirements for HDPE Fusion Testing 7
HDPE Fusion Practical Test (Sample) 9
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 2
CITY OF PALO ALTO: HDPE Water and Sewer Pipe Fusion Procedures
It is the responsibility of a fuser to verify that polyethylene pipe and fittings are in conformance
with the specifications requirements and no older than 6 months from the date of manufacture to
the date of arrival to CPA for black with blue stripe polyethylene water pipe or grey with green
stripe polyethylene sewer pipe.
A. HEAT FUSION TOOLS
1. BUTT FUSION
NOTE: The manufacturer’s operating instructions must be adhered to insure acceptable fusions.
a. Heating Iron
The heating irons are NOT EXPLOSION PROOF and shall not be used in any area with gas
present while still connected to a power source.
An electrically resistive coil in the heating iron maintains the temperature at a level sufficient for
fusion. The irons operate on 110 volts A.C. with power requirements ranging from 1200 watts
McElroy No. 14 to 1750 watts McElroy No. 28 Auto Mac. Teflon coated faces are utilized on both
sides of the iron. Extreme care must be exercised to avoid scratching the faces; only cotton cloths
should be used for cleaning. The faces are either an integral part of the iron or are detachable and
must be recoated when scratched. A dial type thermometer is placed next to the handle. The iron
temperature can be adjusted by changing the calibration set screw. The heating iron for the Auto
Mac must be connected to the proper outlet on the butt fusion machine, DO NOT attach the iron to
any other source as it does not self- regulate and it will be burned out.
b. Butt Fusion Machine
The butt fusion machine consists of mobile and stationary alignment clamps that hold the pipe
ends during the fusion process. These clamps transfer the force and associated pressure required
to fuse the pipe.
c. Alignment Clamp Inserts
Two sizes of inserts are supplied for the 4" machines (2" and 3" IPS). The No. 28 machine also
has two inserts (4" and 6" IPS).
d. Facer
Either manual or electrical facers are provided for the butt fusion machines. The electrical facers
are NOT EXPLOSION PROOF and shall not be used in any area with gas present.
2. ELECTRO FUSION
NOTE: The manufacturer’s operating instructions must be adhered to insure acceptable fusions.
a. Universal Control Box
This unit controls the fusion process. It processes information received from the optical wand that
is used to determine the fitting manufacturer and appropriate fusion times. It also stores fusion
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 3
related information, which can be downloaded for record information.
b. Barcode wand or Hand-held Scanner
This device reads the uniform product code UPC sticker on the fitting.
c. Electrofusion (E.F.) Couplings
A resistant wire embedded in the coupling provides the energy required for fusion.
i. Alignment Clamps
Only required for 2" and larger sizes. These devices align and immobilize the pipe ends and
coupling during the fusion and cool down periods.
ii. Pipe Scrapers
Three types of scrapers are used to remove oxidation and contaminants from the outside pipe
wall prior to electro fusion coupling installation. A paint scraper may be used on 1/2" and 1"
CTS sizes only. Virax type or interior anchored pipe scraper can be used on 1/2" CTS - 6" IPS
sizes. Additionally, full encirclement Scrapers can be used on 2" - 8" pipe sizes.
d. Tapping Tees
The tees also have a resistant wire coil that provides the energy for fusion. They require either a
back up under saddle or a ratchet operated clamp to fix the tee to the main during fusion. A
threaded cutter is included for tapping the main.
i. Service Line Alignment Clamp
When applying the service line to the outlet of a tapping tee an alignment clamp shall be used
to insure that the outlet and the service line are straight. This unit also immobilizes the
coupling during the fusion and cool down periods.
ii. Ratchet Clamp
All pipe sizes require the use of a hold down clamp or backing plate to secure the tapping tee
onto the main during fusion.
3. MISCELLANEOUS TOOLS
a. Pipe Cutters
i. "Plier" type cutters for use on 1/2" CTS - 2" IPS sizes.
ii. A guillotine type cutter shall be used on 3" and larger sizes.
b. Pipe Squeeze Off Tools
i. Manual squeeze off tools are provided for 1/2" CTS - 2" IPS sizes. These tools are equipped
with stops for each pipe size that prevent over squeezing of the pipe.
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 4
ii. Hydraulic squeeze off tools are necessary for the larger pipe sizes, 3" - 8". These tools are
also equipped with stops for each pipe size.
c. Pyrometer
The pyrometer is used to check the surface temperature of the heating irons. It consists of a hand
held display unit and an attached surface probe.
B. MANUAL BUTT FUSION PROCEDURES (CITY STAFF ONLY)
1. Energize the heating iron. Once the heater has reached maximum temperature, generator cycles off,
check the thermometer for 425° ± 25°F.
At the start of each day, the reading of the dial thermometer shall be checked against the surface
temperature by use of the pyrometer and the heating iron calibration set screw adjusted accordingly
(manual machines only).
NOTE: DO NOT adjust the heating iron for the AutoMac unit as it is regulated (controlled) by the
microprocessor.
2. Install the proper size alignment clamp inserts if required.
3. Inspect the pipe and/or fitting ends and cut off any damaged or flattened portions.
4. Clean each pipe/fitting end with a clean cotton cloth and place them in the alignment clamps. Pipe
ends should overlap the alignment clamps by approximately 1".
5. Place the manual or the motorized facer on the guide rods and bring the pipe ends in contact with it.
Turn the manual facer in the direction of the arrow or turn the motorized facing unit on and apply light
force on the carriage lever to advance the pipe ends. The motorized facer speed will increase when
the pipe has bottomed out.
6. Retract the carriage lever and remove the facer. Discard the strips of material from the pipe ends
taking care not to touch the clean surfaces. Check the discarded strips to insure thatto ensure that a
continuous length from the entire diameter has been removed.
7. Check alignment of the pipe ends and adjust for high-low if necessary. If an adjustment is made or a
visible gap exists between the pipe ends, repeat the procedures from Step 4.
8. Wipe heater with a non-synthetic clean dry cloth and place it on the guide rod(s) and bring the pipe
ends into contact with it. Maintain a light force on the carriage until a small melt bead forms around the
entire circumference of both pipe ends. Relax the force on the carriage but keep both pipe ends in
contact with the heater and start the melt time cycle. Refer to Table 1 for proper melt times.
9. After the melt time has been observed snap the carriage back (open) and quickly remove the heater
being careful not to hit the melt.
10. Inspect the pipe ends for complete melt. Bring the pipe ends together quickly, DO NOT SLAM,
applying only enough pressure to form a double roll back bead. The proper bead thicknesses are
shown in Table 1. Over-pressuring the melt will cause the bead to overlap itself resulting in a sub-
quality fusion due to displacement of the melt to the OD and ID of the joint leaving a cold ring in the
center. Under pressuring can result in inadequate fusion due to insufficient contact pressure in the
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 5
melt area.
11. Maintain the pressure exerted on the fusion area for one minute for 1/2"-4" sizes and for three minutes
for 6". Relaxing the pressure prior to expiration of the cooling time can result in porous fusion
joints.
12. Allow the joint to cool for additional three to four minutes (see Table 1) prior to removal from the
alignment clamps. The pipe can now be handled with care. Complete cooling requires approximately
thirty minutes.
13. Check the melt bead for uniformity and size. If the joint exhibits poor characteristics, determine the
cause, make the necessary corrections, cut out the suspect joint, and repeat the procedure from Step
4.
14. Clean the heater faces with a clean cotton cloth. DO NOT use synthetic cloths or metal implements.
TABLE 1: Manual Butt Fusion Parameters
Pipe Size
Melt Bead
Size
Heating Time
(seconds)
Hold Time
(seconds)
Cooling Time
(minutes)
2" IPS
1/16"-1/8"
15
60
4
3" IPS
1/8"
20
60
4
4" IPS
1/8"
20
60
4
6" IPS
3/16"
30
180
5
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 6
Ref: https://isco-pipe.com/wp-content/uploads/2019/10/2018-ISCO_FusionManual_final.pdf
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 7
C. HYDRAULIC BUTT FUSION PROCEDURES
Follow the appropriate manufacturer's procedures when producing butt fusions with hydraulic equipment.
Review Joint Report generated by DataLoggerTM to confirm fusion success.
D. ELECTRO FUSION PROCEDURES
NOTE: See the Universal Control Box Manufacturer’s literature for fusion information. The manufacturer’s
literature must be adhered to insure acceptable fusions.
In the event that the supply voltage varies outside of the stated limits the fusion cycle will be interrupted. A
new cycle can be started after a ten-minute cool down period has been observed. The fusion system will
automatically adjust the duration of the cycle to compensate for the previously aborted attempt. A
maximum of three attempts may be tried. If the tapping tee has already been tapped, NO retries are
allowed.
E. REQUIREMENTS FOR HDPE FUSION TESTING
Applicants for testing will need to demonstrate a working knowledge of HDPE fusion and equipment
without any assistance. The test will be given as a whole. The Contractor will be required to complete
a minimum 4” butt fusion on a hand machine, a 6” butt fusion on a hydraulic machine with a Data
Logger using a McElroy DL5 or higher, a 4” electrofusion coupling, and a 4x8 electric fusion saddle.
Each fusion applicant must bring the following to the test:
x 4” pipe (DR specific), 6’ long for hand fusion using a McElroy Pit Bull 14 (City Staff Only)
x 6” pipe (DR specific), 6’ long for hydraulic fusion on a McElroy 28, 618 or Acrobat 180 fusion machine
(Contractor and City Staff)
x Minimum of 1 each 4” electrofusion coupling and 4x8 electrofusion saddle (recommend at least 2
each, per person tested)
x 3’ of 8” pipe (DR specific)
x Proper tools required to do the work (scraper cutter, lint free cotton towels, etc.)
x Isopropyl alcohol 95% or greater (99% preferred)
x A working contact or infrared pyrometer, and working generator to power the electrofusion box (with
fuel)
x A working reciprocating saw and blades to cut the pipe
x Extension cords and any other saws or cutters you plan to use on the job. Chainsaws are not
permitted.
x McElroy 2LC fusion machine up to 2” or McElroy Pit Bull 14 – note that irons must have stripper bars
and be clean and in good condition. Facer blades must be clean and in good condition in accordance
with the Manufacturer’s specifications. Any machine not meeting these standards will need to be
repaired by an authorized service center that is recognized by the manufacturer
x McElroy 28, 618 or Acrobat 180 fusion machine– must be clean and in good condition. Facer blades
must be clean and in good condition in accordance with the Manufacturer’s specifications. Any
machine not meeting these standards will need to be repaired by an authorized service center that is
recognized by the manufacturer.
x A working electrofusion box with supporting service maintenance history. Not a rental.
The City of Palo Alto’s electrofusion test is in place to test the operator and the equipment that will be used
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 8
on the job. All equipment must meet manufacturer’s standards per latest ASTM D2657. Contractor
shall note that the fusion testing process is a separate process from the City’s project review and
acceptance process.
It is the Contractor’s responsibility to ensure that all equipment is fueled prior to the test being
administered. All equipment must have a serial number or equipment number. Any missing tools or
equipment will result in no test being conducted, or a FAIL will be given. All materials should be what will
be used on the project of which the Contractor is being certified.
See Specification 2300 (Polyethylene Pipe Installation for Water, Gas and Wastewater) for additional
testing requirements.
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 9
CITY OF PALO ALTO: HDPE Fusion Practical Test (Sample)
Applicants for fusion certification will be required to pass both a physical and written exam prior to
being certified.
Name:_______________________ Date:________________
Title:________________________ Company:____________
Individual should be tested on all procedures he/she is to be certified under. (Unmarked boxes constitute
failure in that type procedure).
□ ELECTRO FUSION COUPLINGS
□ 1. Pipe ends were cut square and even.
□ 2. Cleaned pipe ends inside and out.
□ 3. Measured and marked pipe ends.
□ 4. Scraped pipe ends.
□ 5. Took proper precautions to avoid contamination of pipe ends.
□ 6. Cleaned fitting and pipe ends with alcohol.
□ 7. Centered fitting between marks.
□ 8. Connected control box to proper 110 volt A.C. power source in correct sequence.
□ 9. Had thorough understanding of operation sequence and warning light functions.
□ 10. Noted time that FUSION START BUTTON was depressed.
□ 11. Marked time of day on pipe at end of fusion.
□ 12. Removed leads from fitting 30 seconds or longer after fusion was over.
□ 13. Allowed fitting to cool in secured position for recommended time.
□ ELECTRO FUSION TAPPING TEES
□ 1. Cleaned pipe around fusion zone.
□ 2. Scraped entire pipe surface that will fall under tee.
□ 3. Took proper precautions to avoid contamination of scraped pipe.
□ 4. Cleaned fitting and scraped area with alcohol.
□ 5. Placed tee on scraped area.
□ 6. Properly installed under-saddle/hold-down clamp.
□ 7. Connected control box to proper 110 volt A.C. power source in correct sequence.
□ 8. Had thorough understanding of operation sequence and warning light functions.
□ 9. Swiped fitting UPC with optical wand.
□ 10. Noted time that FUSION START BUTTON was depressed.
□ 11. Marked time of day on pipe at end of fusion.
□ 12. Removed leads from fitting 30 seconds or longer after fusion was over.
□ 13. Allowed fitting to cool in secured position for recommended time.
□ BUTT FUSION MANUAL (CITY STAFF ONLY)
□ 1. Pipe ends were faced properly to the facer stops.
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 10
□ 2. Removed cuttings from interior of pipe.
□ 3. Aligned pipe ends for “high-low”, refaced if needed.
□ 4. Cleaned heater face and verified heating iron surface temperature with pyrometer.
□ 5. Observed recommended melt bead prior to timing.
□ 6. Observed recommended melt time.
□ 7. Maintained pressure on fusion during recommended cool down period.
□ 8. Allowed joint to cool in machine for recommended period.
□ 9. Knowledge of rough handling time.
□ BUTT FUSION HYDRAULIC
□ 1. Completed an inspection of equipment for cleanliness and proper operation.
□ 2. Cleaned pipe ends inside and out.
□ 3. Pipe ends were faced properly to the facer stops.
□ 4. Shavings and chips removed after facing pipe.
□ 5. Pipe ends brought together under facing pressure, no visual gaps observed.
□ 6. Aligned pipe ends for “high-low”, refaced if needed.
□ 7. Checked for pipe slippage at fusion pressure and pipe ends kept closed.
□ 8. Calculated drag pressure properly. Drag Pressure __________psi.
□ 9. Theoretical Fusion Pressure Calculated. Theoretical pressure __________psi.
□ DataLogger □Fusion Pressure Calculator
□ McCalc □ Formula
Observed gauge pressure (theoretical fusion pressure + drag) used to fuse the pipe
__________psi.
□ 10. Cleaned heater face and verified heating iron surface temperature with pyrometer.
□ 11. Recommended shift sequence followed.
□ 12. Bead size against the heater meet standard before heater removal.
□ 13. Inspected pipe interfacial area after heater removal.
□ 14. Removal of heater completed in allotted time.
□ 15. Completed cooling cycle time (under fusion pressure).
□ 16. Operator proficient with Data Logger setup and operation.
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 11
JOINT EVALUATION
Visual Examination (During and after assembly. Compare to Photograph or sample of acceptable joint.)
Procedure/Joint Appearance
PROCEDURE
JOINT
APPEARANCE
ADDITIONAL
INSTRUCTION REQUIRED
IN PASS FAIL
BUTT FUSION (MANUAL) _____”
BUTT FUSION (HYDRAULIC) _____”
ELECTRO
COUPLING _____”
FUSION
TAPPING TEE _____”
□ DEFORMATION TEST ≤ 3” TENSILE TEST ≥ 4”
□ Specimen cut into test template or longitudinal straps. (Joint should be free of voids or unbonded areas
on surface.)
Joint Evaluation (Visual)(Deform joint by bending or tensile test)
PROCEDURE
JOINT
APPEARANCE
ADDITIONAL
INSTRUCTION REQUIRED
IN PASS FAIL
BUTT FUSION (MANUAL) _____”
BUTT FUSION (HYDRAULIC) _____”
ELECTRO
COUPLING _____”
FUSION
TAPPING TEE _____”
Certification obtained in the following utility (s)
FUSION PROCEDURES AND CERTIFICATION (WATER AND SEWER) SECTION 2400
CITY OF PALO ALTO Section 2400 PAGE 12
□Water □Wastewater
RECOMMENDATION:
□ Retest Required.
□ Certification Card Issued/Date _______________________
□ Re-Certification Card Issued/Date ____________________
Certified in the following application(s):
□ Butt Fusion
□ Couplings
□ Tapping Tees
_________________________________________ __________________________
Employee Signature Date
______________________________ ______________________________ _____________
Evaluator Name and Title Evaluator Signature Date
FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 1
SECTION 2500
FUSION PROCEDURES AND CERTIFICATION (GAS)
Revised 02/26/20
TABLE OF CONTENTS
PAGE
SUBJECT NUMBER
Heat Fusion Tools 2
Manual Butt Fusion Procedure (City Staff Only) 4
Hydraulic Butt Fusion Procedure 5
Electro Fusion Procedure 6
Requirements for PE Fusion Testing 6
Polyethylene Gas Pipe Fusion Practical Test (Sample) 8
FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 2
CITY OF PALO ALTO: Polyethylene Gas Pipe Fusion Procedures
It is responsibility of a fuser to verify that polyethylene pipe and fittings are in conformance with
the specifications requirements and no older than 6 months from the date of manufacture to the
date of arrival to CPA.
A. HEAT FUSION TOOLS
1. BUTT FUSION
NOTE: The manufacturer’s operating instructions must be adhered to insure acceptable fusions.
a. Heating Iron
The heating irons are NOT EXPLOSION PROOF and shall not be used in any area with gas
present while still connected to a power source.
An electrically resistive coil in the heating iron maintains the temperature at a level sufficient for
fusion. The irons operate on 110 volts A.C. with power requirements ranging from 1200 to 1750
watts. Teflon coated faces are utilized on both sides of the iron. Extreme care must be exercised
to avoid scratching the faces; only lint free cloths should be used for cleaning. The faces are
either an integral part of the iron or are detachable and must be replaced when scratched. A dial
type thermometer is placed next to the handle. The iron temperature can be adjusted by
changing the calibration set screw.
b. Butt Fusion Machine
Machine shall be the hydraulic fusion machine with built-in hydraulic pipe lift to assist with the
pipe handling and incorporating centerline guidance system and DataLoggerTM compatible, and
capable of butt fusion of most fittings without special holders or removal of jaw. Contractor to
provide hydraulic McElroy butt fusion machine or approved equal.
c. Alignment Clamp Inserts
Sufficiently sized alignment clamps must be included with the butt fusion machine for the
diameter of pipe(s) to be fused.
d. Facer
1. Electrical facers must be used with the butt fusion machines. Facer shall have sharp properly
aligned blades. The electrical facers are NOT EXPLOSION PROOF and shall not be used in
any area with gas present.
2. ELECTRO FUSION
NOTE: The manufacturer’s operating instructions must be adhered to insure acceptable fusions. All
electrofusion boxes must be calibrated at intervals not exceeding 3 years, or more often if
manufacturer recommends accelerated calibration interval.
a. Universal Control Box
The Contractor shall provide a universal electrofusion control box, capable of storing a minimum
of 100 fusion records. All previous fusions must be completely cleared from the box memory prior
to arriving for testing.
FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 3
b. Electric Generator
Contractor shall provide the necessary power supply to meet the power requirements as
specified by the manufacturer of the fusion equipment. Generator shall be in new condition and
have a minimum rated capacity of 5 kW for 8” and smaller and 10 KW for 10” and larger.
c. Barcode Wand or Hand-held Scanner
This device reads the uniform product code UPC sticker on the fitting.
d. Electrofusion Couplings
A resistant wire embedded in the coupling provides the energy required for fusion.
i. Alignment Clamps
Are required for 1" and larger diameter pipelines. These devices align and immobilize the
pipe ends and coupling during the fusion and cool down periods.
ii. Pipe Scrapers
Three types of scrapers are used to remove oxidation and contaminants from the outside
pipe wall prior to electro fusion coupling installation. Virax type or interior anchored pipe
scraper can be used on 1/2" CTS - 6" IPS sizes. Additionally, full encirclement Scrapers can
be used on 2" - 8" pipe sizes.
e. Tapping Tees
The tees also have a resistant wire coil that provides the energy for fusion. They require either a
back up under saddle or a ratchet operated clamp to fix the tee to the main during fusion. A
threaded cutter is included for tapping the main.
i. Service Line Alignment Clamp
When applying the service line to the outlet of a tapping tee an alignment clamp shall be
used to insure that the outlet and the service line are straight. This unit also immobilizes the
coupling during the fusion and cool down periods.
ii. Ratchet Clamp
All pipe sizes require the use of a hold down clamp or backing plate to secure the tapping tee
onto the main during fusion.
3. MISCELLANEOUS TOOLS
a. Pipe Cutters
i. "Plier" type cutters may be used for pipelines 1/2" CTS - 2" IPS in diameter.
ii. For 3” – 12” diameter pipe, guillotine style pipe cutter outfitted with a ratchet drive or power
driven designed to cut medium density polyethylene pipe may be used. A reciprocating saw
may be used to cut pipe, as long as all cleaning and pipe facing applications are performed.
b. Pyrometer
FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 4
The Contractor shall provide a pyrometer capable of testing the temperature of the heating iron,
while at fusion temperature, to an accuracy of 0.5% (r3qF). The fusion temperature of the
heating iron shall be verified prior to testing. A handheld display unit with infrared beam or
attached surface probe may be used.
B. MANUAL BUTT FUSION PROCEDURES (CITY STAFF ONLY)
1. Energize the heating iron. Once the heater has reached maximum temperature, generator cycles off,
check the thermometer for 425° ± 25°F.
At the start of each day, the reading of the dial thermometer shall be checked against the surface
temperature by use of the pyrometer and the heating iron calibration set screw adjusted accordingly
(manual machines only).
2. Install the proper size alignment clamp inserts if required.
3. Inspect the pipe and/or fitting ends and cut off any damaged or flattened portions.
4. Clean each pipe/fitting end with a clean lint free cloth and place the pipe in the alignment clamps.
Pipe ends should overlap the alignment clamps by approximately 1".
5. Place the manual or the motorized facer on the guide rods and bring the pipe ends in contact with it.
Turn the manual facer in the direction of the arrow or turn the motorized facing unit on and apply light
force on the carriage lever to advance the pipe ends. The motorized facer speed will increase when
the pipe has bottomed out.
6. Retract the carriage lever and remove the facer. Discard the strips of material from the pipe ends
taking care not to touch the clean surfaces. Check the discarded strips to insure thatto ensure that a
continuous length from the entire diameter has been removed.
7. Check alignment of the pipe ends and adjust for high-low if necessary. If an adjustment is made or a
visible gap exists between the pipe ends, repeat the procedures from Step 4.
8. Wipe heater with a non-synthetic clean lint free cloth and place it on the guide rod(s) and bring the
pipe ends into contact with it. Maintain a light force on the carriage until a small melt bead forms
around the entire circumference of both pipe ends. Relax the force on the carriage but keep both
pipe ends in contact with the heater and start the melt time cycle. Refer to Table 1 for proper melt
times.
9. After the melt time has been observed snap the carriage back (open) and quickly remove the heater
being careful not to hit the melt.
10. Inspect the pipe ends for complete melt. Bring the pipe ends together quickly, DO NOT SLAM,
applying only enough pressure to form a double roll back bead. The proper bead thicknesses are
shown in Table 1. Over-pressuring the melt will cause the bead to overlap itself resulting in a
subquality fusion due to displacement of the melt to the OD and ID of the joint leaving a cold ring in
the center. Under pressuring can result in inadequate fusion due to insufficient contact pressure in
the melt area.
11. Maintain the pressure exerted on the fusion area for one minute for 1/2"-4" sizes and for three
minutes for 6". Relaxing the pressure prior to expiration of the cooling time can result in porous
fusion joints.
12. Allow the joint to cool for additional three to four minutes (see Table 1) prior to removal from the
alignment clamps. The pipe can now be handled with care. Complete cooling requires
FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 5
approximately thirty minutes.
13. Check the melt bead for uniformity and size. If the joint exhibits poor characteristics, determine the
cause, make the necessary corrections, cut out the suspect joint, and repeat the procedure from Step
4.
14. Clean the heater faces with a clean cotton cloth. DO NOT use synthetic cloths or metal implements.
TABLE 1: Manual Butt Fusion Parameters
Pipe Size
Melt Bead
Size
Heating Time
(seconds)
Hold Time
(seconds)
Cooling Time
(minutes)
1/2" CTS
1/16"
3-6
60
3
1" CTS
1/16"
5-9
60
3
2" IPS
1/16"-1/8"
15
60
4
3" IPS
1/8"
20
60
4
4" IPS
1/8"
20
60
4
6" IPS
3/16"
30
180
5
C. HYDRAULIC BUTT FUSION PROCEDURES
1. Energize the heating iron. Once the heater has reached maximum temperature, generator cycles off,
check the thermometer for 425° ± 25°F.
At the start of each day, the reading of the dial thermometer shall be checked against the surface
temperature by use of the pyrometer and the heating iron calibration set screw adjusted accordingly
(manual machines only).
2. Install the proper size alignment clamp inserts if required.
3. Inspect the pipe and/or fitting ends and cut off any damaged or flattened portions.
4. Clean each pipe/fitting end with a clean lint free cloth and place the pipe in the alignment clamps.
Pipe ends should overlap the alignment clamps by approximately 1".
5. Place the motorized facer on the guide rods and bring the pipe ends in contact with it. Turn on the
motorized facing unit and advance the pipe ends into the facing unit. The motorized facer speed will
increase when the pipe has bottomed out.
6. Retract the carriage and remove the facer. Discard the strips of material from the pipe ends taking
care not to touch the clean surfaces. Check the discarded strips to insure that a continuous length
from the entire diameter has been removed.
7. Check alignment of the pipe ends and adjust for high-low if necessary. If an adjustment is made or a
FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 6
visible gap exists between the pipe ends, repeat the procedures from Step 4.
8. Wipe heater with a non-synthetic clean lint free cloth and place it on the guide rod(s) and bring the
pipe ends into contact with it. The carriage should be placed in heat soak until a small melt bead
forms around the entire circumference of both pipe ends. Refer to Table 1 for proper melt times.
9. After the melt time has been observed the carriage should be opened and quickly remove the heater
being careful not to hit the melt.
10. Inspect the pipe ends for complete melt. Bring the pipe ends together quickly until a double roll back
bead is formed. The proper bead thicknesses are shown in Table 1.
11. Maintain the pressure exerted on the fusion area until required.
12. Allow the joint to cool for additional three to four minutes (see Table 1) prior to removal from the
alignment clamps. The pipe can now be handled with care. Complete cooling requires
approximately thirty minutes.
13. Check the melt bead for uniformity and size. If the joint exhibits poor characteristics, determine the
cause, make the necessary corrections, cut out the suspect joint, and repeat the procedure from Step
4.
14. Clean the heater faces with a clean cotton cloth. DO NOT use synthetic cloths or metal implements.
D. ELECTRO FUSION PROCEDURES
NOTES: See the Universal Control Box Manufacturer’s literature for fusion information. The
manufacturer’s literature must be adhered to insure acceptable fusions.
In the event that the supply voltage varies outside of the stated limits the fusion cycle will be interrupted.
A new cycle can be started after a ten-minute cool down period has been observed. The fusion system
will automatically adjust the duration of the cycle to compensate for the previously aborted attempt. A
maximum of three attempts may be tried. If the tapping tee has already been tapped, NO retries are
allowed.
E. REQUIREMENTS FOR PE FUSION TESTING
Applicants for testing will need to demonstrate a working knowledge of Polyethylene pipe fusion
procedures and equipment without any assistance. The test will be given as a whole. The Contractor
will be required to complete a minimum 6” butt fusion on a hydraulic machine with a Data Logger
using a McElroy DL5 or higher, a 4” electrofusion coupling, and a 2”x6” electrofusion service tee
saddle. A 2” butt fusion on a hydraulic machine with a Data Logger using a McElroy DL5 or higher
may be required if 2” Polyethylene pipe will be installed.
Each fusion applicant must bring the following to the test:
x 2” pipe (DR 11), 6’ long and performed on a hydraulic fusion machine (if applicable)
x 6” pipe (DR 11.5), 6’ long and performed on a hydraulic fusion machine
x Minimum of 1 each 6” electrofusion coupling and 2”x6” electrofusion service tee saddle
(recommend at least 2 each, per person tested)
x Proper tools required to do the work (scraper cutter, lint free cloths, etc.)
x Isopropyl alcohol 95% or greater (99% preferred)
x A working contact or infrared pyrometer, and working generator to power the electrofusion box
(with fuel)
FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 7
x A working reciprocating saw and blades to cut the pipe
x Extension cords and any other saws or cutters you plan to use on the job. Chainsaws are not
permitted.
x For manual fusion only (City Staff) 2LC or up to 2” or PitBull 14 – irons must have stripper bars
and be clean and in good condition. Facer blades must be clean and in good condition in
accordance with the Manufacturer’s specifications. Any machine not meeting these standards will
need to be repaired by an authorized service center that is recognized by the manufacturer
x For hydraulic fusion only (Contractor and City Staff) 28, 618 or Acrobat 180 – irons must have
stripper bars and be clean and in good condition. Facer blades must be clean and in good
condition in accordance with the Manufacturer’s specifications. Any machine not meeting these
standards will need to be repaired by an authorized service center that is recognized by the
manufacturer.
x A calibrated and working electrofusion box. Not a rental.
The City of Palo Alto’s electrofusion test is in place to test the operator and the equipment that will be
used on the job. All equipment must meet manufacturer’s standards per ASTM F1055 and
F2620. Contractor shall note that the fusion testing process is a separate process from the City’s
project review and acceptance process.
It is the Contractor’s responsibility to ensure that all equipment is fueled prior to the test being
administered. All equipment must have a serial number or equipment number. Any missing tools
or equipment will result in no test being conducted, or a FAIL will be given. All equipment used for
Contractor certification, should be the same equipment used on the project.
See Specification 2300 (Polyethylene Pipe Installation for Water, Gas and Wastewater) for additional
testing requirements.
FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 8
CITY OF PALO ALTO: Polyethylene Gas Pipe Fusion Practical Test (Sample)
Applicants for fusion certification will be required to pass both a physical and written exam prior to
being certified.
Name:_______________________ Date:________________
Title:________________________ Company:____________
Individual should be tested on all procedures he/she is to be certified under. (Unmarked boxes constitute
failure in that type procedure).
□ ELECTRO FUSION COUPLINGS
□ 1. Pipe ends were cut square and even.
□ 2. Cleaned pipe ends inside and out.
□ 3. Measured and marked pipe ends.
□ 4. Scraped pipe ends.
□ 5. Took proper precautions to avoid contamination of pipe ends.
□ 6. Cleaned fitting and pipe ends with alcohol.
□ 7. Centered fitting between marks.
□ 8. Connected control box to proper 110 volt A.C. power source in correct sequence.
□ 9. Had thorough understanding of operation sequence and warning light functions.
□ 10. Noted time that FUSION START BUTTON was depressed.
□ 11. Marked time of day on pipe at end of fusion.
□ 12. Removed leads from fitting 30 seconds or longer after fusion was over.
□ 13. Allowed fitting to cool in secured position for recommended time.
□ ELECTRO FUSION TAPPING TEES
□ 1. Cleaned pipe around fusion zone.
□ 2. Scraped entire pipe surface that will fall under tee.
□ 3. Took proper precautions to avoid contamination of scraped pipe.
□ 4. Cleaned fitting and scraped area with alcohol.
□ 5. Placed tee on scraped area.
□ 6. Properly installed under-saddle/hold-down clamp.
□ 7. Connected control box to proper 110 volt A.C. power source in correct sequence.
□ 8. Had thorough understanding of operation sequence and warning light functions.
□ 9. Swiped fitting UPC with optical wand.
□ 10. Noted time that FUSION START BUTTON was depressed.
□ 11. Marked time of day on pipe at end of fusion.
□ 12. Removed leads from fitting 30 seconds or longer after fusion was over.
□ 13. Allowed fitting to cool in secured position for recommended time.
□ BUTT FUSION MANUAL (CITY STAFF)
□ 1. Pipe ends were faced properly to the facer stops.
□ 2. Removed cuttings from interior of pipe.
□ 3. Aligned pipe ends for “high-low”, refaced if needed.
FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 9
□ 4. Cleaned heater face and verified heating iron surface temperature with pyrometer.
□ 5. Observed recommended melt bead prior to timing.
□ 6. Observed recommended melt time.
□ 7. Maintained pressure on fusion during recommended cool down period.
□ 8. Allowed joint to cool in machine for recommended period.
□ 9. Knowledge of rough handling time.
□ BUTT FUSION HYDRAULIC
□ 1. Completed an inspection of equipment for cleanliness and proper operation.
□ 2. Cleaned pipe ends inside and out.
□ 3. Pipe ends were faced properly to the facer stops.
□ 4. Shavings and chips removed after facing pipe.
□ 5. Pipe ends brought together under facing pressure, no visual gaps observed.
□ 6. Aligned pipe ends for “high-low”, refaced if needed.
□ 7. Checked for pipe slippage at fusion pressure and pipe ends kept closed.
□ 8. Calculated drag pressure properly. Drag Pressure __________psi.
□ 9. Theoretical Fusion Pressure Calculated. Theoretical pressure __________psi.
□ DataLogger □Fusion Pressure Calculator
□ McCalc □ Formula
Observed gauge pressure (theoretical fusion pressure + drag) used to fuse the pipe
__________psi.
□ 10. Cleaned heater face and verified heating iron surface temperature with pyrometer.
□ 11. Recommended shift sequence followed.
□ 12. Bead size against the heater meet standard before heater removal.
□ 13. Inspected pipe interfacial area after heater removal.
□ 14. Removal of heater completed in allotted time.
□ 15. Completed cooling cycle time (under fusion pressure).
□ 16. Operator proficient with Data Logger setup and operation.
FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 10
JOINT EVALUATION
Visual Examination (During and after assembly. Compare to Photograph or sample of acceptable joint.)
Procedure/Joint Appearance
PROCEDURE
JOINT
APPEARANCE
ADDITIONAL
INSTRUCTION REQUIRED
IN PASS FAIL
BUTT FUSION (MANUAL) _____”
BUTT FUSION (HYDRAULIC) _____”
ELECTRO
COUPLING _____”
FUSION
TAPPING TEE _____”
□ DEFORMATION TEST ≤ 3” TENSITE TEST ≥ 4”
□ Specimen cut into test template or longitudinal straps. (Joint should be free of voids or unbonded areas
on surface.)
Joint Evaluation (Visual)(Deform joint by bending or tensile test)
PROCEDURE
JOINT
APPEARANCE
ADDITIONAL
INSTRUCTION REQUIRED
IN PASS FAIL
BUTT FUSION (MANUAL) _____”
BUTT FUSION (HYDRAULIC) _____”
ELECTRO
COUPLING _____”
FUSION
TAPPING TEE _____”
Certification obtained in the following utility (s)
□Gas
FUSION PROCEDURES AND CERTIFICATION (GAS) SECTION 2500
CITY OF PALO ALTO Section 2500 Page 11
RECOMMENDATION:
□ Retest Required.
□ Certification Card Issued/Date _______________________
□ Re-Certification Card Issued/Date ____________________
Certified in the following application(s):
□ Butt Fusion
□ Couplings
□ Tapping Tees
_________________________________________ __________________________
Employee Signature Date
______________________________ ______________________________ _____________
Evaluator Name and Title Evaluator Signature Date
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 1
SECTION 2660
WATER DESIGN AND CONSTRUCTION STANDARDS
PART 1 – GENERAL
1.01 DESCRIPTION
Work Includes installation of high density polyethylene (HDPE) water mains, water and fire services,
fire hydrants, tracer wire, water valves and boxes, mechanical joint and/or flange adapters, all
appurtenances, and all related equipment and fittings in accordance with the requirements of the
Contract Documents.
1.02 RELATED WORK
Section 2200: Excavation, Backfill and Restoration
PART 2 – DESIGN STANDARDS
2.01 PIPE SIZE
A. Minimum size of new main:
The minimum size of new HDPE water main shall be 8” (I.D. = 6.963), SDR 11.
B. Minimum size of new service:
The minimum size of new HDPE water service shall be 2” (I.D. = 1.815), SDR 9.
C. Calculating Service Size:
The service size calculation must be based on the Hazen-Williams Formula to calculate the head
loss due to pipe friction.
2.02 COVER AND CLEARANCES
A. Minimum/Maximum Cover:
1. Water mains shall be installed with a minimum and maximum cover, as measured vertically
from the top of pipe to the top of pavement. For 8” HDPE, a minimum depth of 3-feet is
required, with a maximum of 4.5-feet. For 10” and larger HDPE, a minimum depth of 4-feet is
required, with a maximum of 5.5-feet. Upon approval of the engineer, exceptions may be
allowed if existing conditions do not allow for the required minimum and maximum depths to
be maintained.
2. Water services shall be installed with a minimum cover of 24”, as measured vertically from
the top of pipe to the top of pavement. The maximum depth of installation shall not exceed
30”.
B. Underground Clearances:
1. Sewer, Recycled Water and Storm Utility Separation: For parallel construction, the distance
between new water mains and sewer, recycled water and storm drain lines shall follow the
State Water Resources Control Board’s separation requirements. Separation distances shall
be measured from the nearest edge of the facilities. Water mains and non-potable fluid-
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 2
carrying pipelines shall not be installed in the same trench. In the event that the minimum
clearances cannot be achieved, the City and the State Water Resources Control Board will
need to approve the plans. Any changes due to field conditions during construction that
decreases the separation will need to be reapproved prior to installation.
2. Gas, Electric, and other Utility Structures: For all other utilities, unless otherwise specified, a
minimum of 12-inches vertically and 48- inches horizontally shall be maintained between the
pipe surface and other utility line or structures. In the event that it is not possible to maintain
the required minimum vertical clearance from other structures, the Contractor shall encase
the water main in steel pipe or concrete at the discretion of the engineer. If horizontal
separation is between 1-foot and 4-foot, review and approval by the engineer is required.
Horizontal separation less than 1’ is prohibited.
2.03 LOCATIONS
A. Water mains shall be located 7-feet off the lip of gutter/edge of pavement on the north or east
side of streets, if possible, unless otherwise specified on the Project Drawings.
B. Water services shall be installed perpendicular from the water main, in the shortest straight line
to the water meter.
C. The minimum distance between service taps shall be 24 inches.
D. Water meters and services shall be installed 5-feet minimum from trees, edge of driveway, and
the sanitary sewer house lateral.
E. Water meters 2” and smaller in size shall be installed in the public right-of-way. The meter
location and installation shall conform to the WGW Utility Standard Details.
F. Water meters larger than two inches in size shall be installed on the customer's property,
adjacent to the customer’s property line.
G. The meter location and installation shall conform to the WGW Utility Standard Details.
2.04 METER BYPASSES
Some customers, such as hospitals, schools, beauty shops, and factories with processes requiring
uninterrupted water service, shall have bypasses installed around the meter so that tests and repairs
can be carried out without inconvenience to either the customer or the utility.
2.05 AVAILABLE PRESSURE
The water pressures in the distribution system vary with elevations of the area served. During
average demand conditions, pressures range from 40 to 125 psi, with an average of approximately
50 psi. The lowest design pressure that should be used is 40 psi. However, the City does not
guarantee a specific water main pressure, during peak hour and/or emergency conditions, as certain
areas of the City are subject to inadequate pressures. The water pressure in Foothill, west of
highway 280, may be as high as 200 psi.
For the design of fire protection systems requirements and request of Fire Hydrant Flow Data, the
service designer must consult the Palo Alto Fire Prevention Bureau at the Development Center
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 3
located at 285 Hamilton Avenue, 1st Floor, Palo Alto, CA 94301, Phone (650) 617-3184. For an
estimate of static pressure at the water supply main, contact WGW Utilities Engineering Development
Services at (650) 566-4501.
2.06 VALVES
A. Main Valves:
All main line valves shall be installed per Section 4.01A.13 of this Specification. Four water
valves shall be installed at each water main intersection or cross, and three valves shall be
installed at each water main tee at the City’s right-of-way line projection at the intersection.
Valve spacing shall not exceed 500 LF unless approved by the City. See Figure 1 below. A 2”
HDPE bypass with 2” full port ball valve (NSF 61 listed) shall be installed around each 14” and
larger gate valve to facilitate operation of the valve (standard detail WD-14). For installation
requirements in contaminated areas see Section 2.10 of this Specification.
Where no permanent road features are available in the right-of-way, the valves shall be located
by a “blue” fiberglass utility marking post, offset 5-feet from the mains, and marked with a utility
decal with the words "WATER VALVE" on both sides of the marker.
Install four valves at Install three valves at
each water main intersection each water main tee
Figure 1.
B. Blowoffs And Air Release Valves:
Water mains shall not be designed as dead-end mains. Easements shall be provided to cross-
tie water mains in cul-de-sacs, and as required by the City. Blowoffs shall be provided at all low
points and as required by the City. Temporary blowoffs shall be provided as necessary to
pressure test and chlorinate new water main. Vacuum and air release valves shall be installed at
all summits in the water main, and as directed by the City.
C. Pressure Reducing Valves:
Pressure reducing valves (PRVs) are used in mountainous and hilly areas to control the
downstream pressure and protect the property owner’s plumbing from excessive pressure when
his building is located in the lower elevations of the pressure zone. These are installed by the
customer at the meter or at a suitable location in the customer’s plumbing system to permit
reduced pressure to the house fixtures. PRV’s must be installed to leave maximum pressure at
outside hydrants. It is customer’s responsibility to install and maintain all PRVs.
2.07 FIRE HYDRANTS
Fire hydrants shall be located no more than 500 feet apart in residential areas and no more than 300
feet apart in the downtown areas. Locations and usage shall comply with City of Palo Alto Utilities
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 4
Rule and Regulation 21.
2.08 ELEVATION OF THE CUSTOMER’S SYSTEM
Customers on hillsides or in high-rise buildings will be affected by the difference in elevation between
the utility’s water main and customer’s outlet. If the customer is at an elevation less than that of the
water main, then he can anticipate a higher pressure than that in the main, and conversely, the
homeowner at a higher elevation than the main will encounter lower water pressure. Multistory
buildings will often be too high to use the available main pressure, and pumping will be necessary. It
is the responsibility of the customer’s engineer to design the system from the meter outlet to
determine the pressure that will be available to meet their demand.
2.09 MAXIMUM VELOCITY OF FLOW
A. For water main: The maximum design flow velocity in any water main shall not exceed 7 feet per
second, based on the maximum calculated loads. Maximum distribution pipeline velocity for
maximum day demand plus fire flows shall not exceed 12 feet per second.
B. For water services: The maximum design flow velocity in any residential or commercial water
service shall not exceed 10 feet per second, based on the maximum calculated loads. Maximum
design flow velocity for dedicated fire services shall not exceed 12 feet per second, based on fire
flow demands.
2.10 INSTALLATION IN CONTAMINATED AREAS
For areas of known contamination or where contaminated soil is found the following materials must
be used:
A. Mains: Ductile iron water pipe (DIP) per Section 4.01A.2 of this Specification.
B. Gaskets: NBR or FKM gaskets, depending on the contamination type/levels. Submittals shall be
approved by the Engineer. Gasket lubricant shall be as specified by the pipe manufacturer.
C. Gate Valves: Gate valves per Section 4.01A.13 of this Specification.
D. Services: 2 CTS inch diameter, Type K copper tubing meeting ASTM B88 copper tubing
specification. If the existing service is not copper, the service shall be replaced with new copper
tubing. All services shall be replaced or reconnected in the original size, or 2” copper, whichever
is larger. Four inch and larger services shall be installed using DIP pipe. All services shall be
installed and/or reconnected in accordance with AWWA C800.
E. Service Saddle: Shall be Mueller BR2B series.
2.11 TEMPORARY WATER MAIN BYPASS SYSTEM (REPLACE-IN-PLACE METHOD)
In order to eliminate water service disruptions to customers who require 24 hour a day service, a
temporary water main bypass system will be required. Temporary water main shall be a minimum of
2-inch diameter unless otherwise specified. Temporary water main is required to be disinfected,
flushed, and sampled prior to any service connections being made. The temporary water main shall
also be tested at static main pressure for a period of 2-hours.
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 5
Bypass piping required for an extended period of time, if directed by the Engineer, shall be buried or
covered by granular material ramps where the pipe crosses bike trails, sidewalks, driveways, roads,
pedestrian crossings, etc. Products used shall be manufactured from water distribution piping and
couplings and shall be NSF approved for potable water use.
2.12 NEW DEVELOPMENTS
The applicant's engineer shall provide the required plans submittals (see list in 2.12.B) including the
estimated water demand needed for the review. City of Palo Alto has developed a Domestic Water
System Hydraulic Model of the entire water supply and distribution system. This model will be
utilized by City of Palo Alto Utilities staff and/or a City consultant to verify the size of the domestic
water system facilities required for each development at the developers cost. When the City deems it
necessary, the Developer will be required to provide a water model of the on-site development,
showing that the development can operate under the provided pressure and load parameters
identified by the City.
A. The recommendations for the new development water system improvements shall include a cost
estimate and suggested design criteria. Development Services staff reserves the right to
determine the system design criteria for each water system based upon conditions that may exist
for a particular location, anticipated level of development, planned use or other criteria.
B. Plan Check Submittal Requirements: All plans or inquiries should be submitted to Development
Services of the engineering department for routing to the appropriate staff for review.
1. The developer/engineer must submit a preliminary utility plan showing the proposed location
of the services (domestic, irrigation, fire service), meters, and backflow devices.
2. Expected average day, maximum day, and peak hour water demand in gallons per minute
(gpm) for domestic and irrigation of the entire development. All assumptions must be
explicitly stated and properly documented.
3. Minimum expected fire flows in gpm required by the Fire Department.
4. Documentation or written correspondence with conditions of approval from Palo Alto Fire
Marshall indicating the development’s fire flow requirements stated in gpm, duration in hours
and residual pressure in psi.
5. Information to determine number of equivalent dwelling units:
a. Raw acreage of the development
b. Number and type of residential units
c. Building square feet (SF) of commercial, retail, industrial, hotel, etc.
6. Changes to the development (units, land use, project or construction phasing, etc...) may
require the City hydraulic model be re-run at the Developers expense.
7. The service design load shall be the total present (and additional future) water demand as
presented on the Utilities Application - Load Sheet.
8. Hydraulic modeling analysis comments are for plan check purposes only. The ultimate
design responsibility resides with the developer’s Engineer-of-Record for the Project.
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 6
2.13 IRRIGATION METERS
Water service for all new and rehabilitated industrial, commercial, and institutional landscaping, and
new and rehabilitated multi-family common areas, requires a permit and/or review by the City and
shall be provided by a separate irrigation meter. This meter shall be designed as an irrigation account
and no other utilities will be billed on such accounts. The customer shall pay for the additional service
according to Utility Rate Schedule W-5.
PART 3 – REGULATORY STANDARDS
3.01 CROSS CONNECTION CONTROL
Cross Connection Control shall be installed per City of Palo Alto Utility Rule and Regulation 21
Section E "Water System Protection” in the SPECIAL WATER UTILITY REGULATION, the revised
California Administrative Code (Title 17, Sections 7583 through 7605), and WGW Utility Standards
Details WD-11 through WD-12D. For further questions contact the Utilities Cross Connection
Inspector at 650-496-6972.
A. Type of Protection Required:
The type of protection provided to prevent backflow into the public water supply will directly
correlate with the degree of hazard that exists on the consumer's premises, as determined by the
Cross-Connection Control Officer. In locations where the water service may not be interrupted
during normal working hours, two parallel backflow preventer assemblies shall be installed
(Reference: California Administrative Code, Title 17, Section 7604).
B. Testing and Maintenance of Backflow Preventers:
The Cross-Connection Control Officer will ensure that adequate maintenance and periodic
testing is provided. Backflow preventers will be tested by a certified tester. Backflow preventers
will be tested at least annually or more frequently if determined to be necessary by the Cross-
Connection Control Officer. When a backflow preventer is found to be defective, it shall be
repaired or replaced within 30 calendar days. Backflow preventers will be tested immediately
after installation, relocation, or repair prior to being placed into service. The Cross-Connection
Control Officer will notify the water user when testing is needed. Reports of testing and
maintenance will be maintained by the City of Palo Alto for a minimum of three years. These
regulations are to be reasonably interpreted. It is the intent of these regulations to recognize that
there are varying degrees of hazard and to apply the principle that the degree of protection
should be commensurate with the degree of hazard. It is recognized that the control of cross-
connections requires cooperation between the City of Palo Alto, the water consumer, and the
Water Resource Control Board. The City of Palo Alto has the primary responsibility to prevent
water from unapproved sources, or any other substance from entering the public water supply
system. The Water Resource Control Board has the overall responsibility for preventing water
from unapproved sources from entering either the potable water system within consumer's
premises or the public water supply (Reference: California Administrative Code, Title 17, Section
7605).
C. Parallel Reduced Pressure Principle Assemblies:
Parallel reduced pressure principle assemblies shall be installed at all locations where the water
cannot be interrupted during normal working hours. Only backflow assemblies approved for the
State of California by USC Foundation for Cross-Connection Control and Hydraulic Research
may be used.
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 7
PART 4 - MATERIALS
4.01 WATER DISTRIBUTION SYSTEM MATERIALS
“Wetted surfaces” of all materials, piping, or plumbing fixtures intended for conveying or dispensing
potable water, supplied under these specifications, must contain less than 0.25% lead by weight in
compliance with AB 1953.
A. Polyethylene (HDPE) Pipe and Fittings:
1. Pipe: All potable water polyethylene pipe supplied under this Specification shall be High
Density Polyethylene Pipe (HDPE) PE 4710 with IPS dimensions conforming to the latest
edition of ANSI/AWWA C901 and C906 and ANSI/NSF Standard 61. Resin used in the
extrusion of water polyethylene pipe shall conform to the latest edition of the ASTM D 3350
Cell classification 445574C, or 445574E, with the specifications stated herein, and shall have
an oxidative resistance category of CC3.
a. All water main pipes shall be black with four (4) equally spaced, single longitudinal blue
stripes. Solid blue pipe may be used, but require prior approval. All water service pipes
shall be black with four (4) equally spaced, single longitudinal blue stripes. Solid blue
pipe may be used, but require prior approval. Both main and service piping shall have
AWWA specification stamp embedment or permanent blue-line print.
b. PENT test values of 2,000 hours min.
c. Pipe dimensions and tolerances: The outside diameter and wall thickness shall be within
the limits specified in Table 1.
Approved Manufacturers: The City of Palo Alto approved PE pipe manufacturer is CP CHEM
Performance Pipe, CSR Poly Pipe Industries, WL Plastics, JM Eagle. Any other PE pipe
manufacturer must receive prior approval.
Table 1: Dimensional Standards for IPS 4710 High Density Polyethylene Pipe
Nominal
IPS Size
Actual
Outside Diameter
(inches)
Minimum
Wall Thickness
(inches)
Average
Inside Diameter
(inches)
Standard Dimension Ratio
(SDR)
(unitless)
2" IPS 2.375 0.264 1.815 9
4" IPS 4.50 0.409 3.633 11
6" IPS 6.625 0.602 5.349 11
8" IPS 8.625 0.784 6.963 11
10" IPS 10.750 0.977 8.679 11
12" IPS 12.750 1.159 10.293 11
14" IPS 14.00 1.273 11.301 11
16" IPS 16.00 1.455 12.915 11
18” IPS 18.00 1.636 14.532 11
2. Fittings: All potable water polyethylene fittings supplied under this Specification shall be high
density 4710 polyethylene manufactured by the injection molding process, pressure class
200 or greater, and conform to the latest edition of ANSI/AWWA C901 and C906 and
ANSI/NSF Standard 61. Fabricated fittings may be installed with prior approval from the City
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 8
Engineer. Resin used in the molding shall conform to the latest addition of the ASTM D 3350
Cell classification 445574C (HDPE 4710) with the specifications stated herein.
a. All fittings shall have the AWWA specification stamp embedment or permanent line print.
All fittings shall be pressure class 200 or greater. Additional pipe thickness required for
saddle fusion fittings and other fittings to reach pressure class 200 shall be on the
outside of the pipe so flow is not constricted.
b. Approved Manufacturers: The City of Palo Alto approved PE pipe manufacturers are
CP CHEM Performance Pipe and Integrity Fusion Products Inc. Any other PE fitting
manufacturer such as CSR Poly Pipe Industries, Central Plastics/Georg Fischer, ISCO,
or equal must receive prior approval.
B. Ductile Iron (DI) Pipe and Fittings:
Upon approval of the Engineer, DI pipe and fittings will be accepted to facilitate water main tie-ins
and valve replacement, or at locations where HDPE cannot be used. For material requirements
in contaminated areas, refer to ‘Installation in Contaminated Areas’ in this Section.
All DI water pipe shall be Class 52 push-on type, in standard lengths to conform to ANSI/AWWA
C151/A21.51, ANSI/AWWA C111/A21.21 and ANSI/AWWA C150/A21.50. DI water pipe shall be
asphalt coated in accordance with ANSI/AWWA C151/A21.51 and shall be lined with cement
mortar lining of 1/16-inch minimum thickness, conforming to ANSI/AWWA C104/A21.4.
Mechanical joint fittings, joint restraints, shall be ductile iron Class 350, and shall be produced in
strict accordance with ANSI/AWWA C104/A21.4, ANSI/AWWA C153/A21.53 and shall conform
to details and dimensions published therein. Mechanical joint offsets shall conform to
ANSI/AWWA C110-82 and offset joints shall conform to ANSI/AWWA C111/A21.11. Push-on
joint ductile iron and cast iron fittings shall be in strict accordance with all applicable terms and
provisions of ANSI/AWWA C110/A21.10 and ANSI/AWWA C153. Joints shall be in accordance
with ANSI/AWWA C111/A21.11.
All DI pipe and fittings shall be encased in blue polyethylene tubing, 8 mil thick minimum, in
accordance with ANSI/AWWA C105/A21.5.
C. Polyvinyl Chloride (PVC) Pipe (DI Fittings):
Upon approval of the Engineer, PVC pipe and ductile iron fittings will be accepted to facilitate
water main tie-ins and valve replacement.
All PVC pipe supplied shall be class 200 meeting the requirements of ANSI/AWWA C900. PVC
pipe shall be no older than 1 year from the date of manufacture to the date of shipment to CPA,
provided the pipe is stored indoors in suitable containers; otherwise the pipe shall be no older
than 6 months from date of manufacture to date of shipment to CPA.
Mechanical joint fittings, joint restraints, for PVC pipe shall be ductile iron in accordance with
ANSI/AWWA C153/A21.53 and ANSI/AWWA C111/A21.11 with a rated working pressure of 350
psi. All tees, crosses, and elbows used with PVC pipe shall have mechanical joint ends.
Reducers shall have mechanical joint by mechanical joint (MJxMJ) ends. All ductile iron fittings
shall have an asphaltic coating in accordance with ANSI/AWWA C153/A21.53 and shall be
cement lined and seal coated with an asphaltic material in accordance with ANSI/AWWA
C104/A21.4. Mechanical joint ductile iron fittings shall be in accordance with ANSI/AWWA
C110/A21.10 and joints shall be in accordance with ANSI/AWWA C111/A21.11.
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 9
Joining standard lengths of PVC pipe shall be with bell ends consisting of an integral wall section
with a locked-in solid cross section elastomeric ring which meets the requirements of ASTM
F477 or couplings supplied by the manufacturer meeting the requirements of AWWA C900.
Additional Outside Agency Approvals: All PVC fittings for use with AWWA C900 pipe shall have
the approval of Factory Mutual (FM) and be listed by Underwriters Laboratories, Inc. (UL).
D. Main Tapping Hardware: All hardware must be ANSI/NSF 61 listed.
1. Tapping Sleeve
a. HDPE Main: For HDPE main connections, saddle shall be HDPE 4710, class 200
electrofusion branch saddle (IPS to IPS), NSF 61 listed and meet or exceed applicable
ANSI/AWWA requirements manufactured by Georg Fischer Central Plastics, or
approved equal. The fittings shall be provided with bottom underclamps or installed
using a loading tool as specified by manufacturer’s installation procedure.
b. Non-HDPE Main: All tapping sleeves shall be epoxy coated with 304 stainless steel
washers, nuts and bolts. Tapping sleeves shall be as follows for Non-HDPE main
connections:
i. CIP/DIP/PVC: Tapping sleeve shall be JCM 6432 all 316 stainless steel, or approved
equal.
ii. ACP: Tapping sleeve shall be JCM 6432 all 316 stainless steel, or approved equal.
iii. CCP: Tapping sleeve shall be JCM 415, or approved equal.
2. Tapping Valves: Tapping valves shall be Mueller A-2361 class 250 ductile iron resilient
wedge gate valve with flange inlets and outlets, EPDM disc and O-rings, and be supplied
with 316 stainless steel washers, nuts and bolts.
E. Main Joining Hardware: All hardware must be ANSI/NSF 61 listed.
1. Electrofusion Couplings (HDPE to HDPE): Electrofusion couplings shall be Georg Fischer
Central Plastics, Integrity IntegriFuse, or approved equal for HDPE 4710, IPS DR 11 (4” and
greater) and DR 9 (2”), Class 200 or greater, and ANSI/NSF 61 listed. HDPE pipe to HDPE
pipe shall be joined by butt or electro fusion.
2. Mechanical Joint (MJ) HDPE Adapter Kit (HDPE to PVC/DIP): Mechanical Joint (MJ) adapter
kit shall be pressure class 200 or greater, designed for fusion to HDPE pipe, and mechanical
connection to DIP or PVC pipe. Glands, material assembly and bolting shall be in
accordance with ANSI A21.11 (AWWA C111); full face rubber gasket shall be included in the
kit. The MJ adapter connection shall provide a fully self-restrained joint and shall not require
additional restraint. MJ adapters shall have AWWA C110 heavy-weight metal glands and
stainless steel stiffeners.
3. Mechanical Couplings: All mechanical couplings (parts) shall be NSF 61 listed and pressure
class 200 or greater and in accordance with ANSI/AWWA C153/A21.53. HDPE pipe shall
have a pipe stiffener at each mechanical coupling joint. Outside pipe diameter shall be
confirmed in the field prior to ordering mechanical couplings.
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 10
a. HDPE to HDPE: Mechanical coupling for joining HDPE when a complete water shutdown
is not possible, and electrofusion couplings cannot be used, shall be a Romac Industries
Alpha Restrained Joint, EBAA Iron Mega-Coupling Series 3800, or approved equal.
b. HDPE to ACP (asbestos cement pipe): Mechanical couplings shall be Smith & Blair 462
Quantum Coupling, Romac Macro HP, EBAA Iron Mega-Coupling Series 3800, or
approved equal, meeting the following minimum requirements:
i. Sleeve: Ductile Iron ASTM A-536 designed for high strength/weight ratio. Ends shall
have smooth inside taper for uniform gasket seating.
ii. Gaskets: Nitrile (Buna N)
iii. Follower Flanges: Ductile Iron ASTM A-536 designed for high strength/weight ratio.
Thickness determined by coupling size.
iv. Bolts & Nuts: 304 Stainless.
v. Finish: Fusion bonded epoxy coating in accordance with AWWA C213.
c. HDPE to CIP (cast iron pipe) or DIP (ductile iron pipe): Mechanical coupling shall be
Krausz Hymax Grip, Smith & Blair 462 Quantum Coupling, Romac Macro HP, EBAA Iron
Mega-Coupling Series 3800, or approved equal.
d. HDPE to PVC (polyvinyl chloride pipe): Mechanical coupling shall be Smith & Blair 462
Quantum Coupling, EBAA Iron Mega-Coupling Series 3800, or approved equal. HDPE
pipe shall be restrained by electrofusion flex restraints, and PVC pipe shall be restrained
using a tapered gripping ring.
e. CCP to DIP or other pipe: Mechanical coupling or coupling adaptor shall comply with
AWWA C219. Confirm the thickness of the steel cylinder pipe. For pipe less than ¼”
steel cylinder thickness use adaptors with a welded buttstrap. Follow manufacturer’s
recommendations for both couplings and adaptors. The coupling or adaptor shall be
Romac 400 series or approved equal.
4. Joint Restraints: All joint restraints shall be EBAA IRON 2000PV for PVC pipe and EBAA
IRON MEGALUG 1100 series for ductile iron pipe, or approved equal.
5. Mechanical Joint Bolts: Bolts for mechanical joint glands shall be Central Steel Services, Inc.
Corten T-Bolts, or approved equal, and shall be high strength, low alloy steel bolts only,
meeting the requirements of ANSI/AWWA C111/A 21.11 for rubber gasket joints for cast iron
or ductile iron pipe and fittings.
6. HDPE to Flange Connection: HDPE flange adapter shall be pressure class 200 or greater
and used to join HDPE pipe to an existing flange or gate valve. A backup ring for flange
adapter shall be pressure class 200 or greater and stainless. HDPE flange adapter shall
meet requirements specified in Subsection 7 and 8 for bolts, nuts and gaskets. the following
minimum requirements:
a. Bolts & Nuts: 304 stainless.
b.a. Gasket: Garlock Blue-Gard 3000 gasket, blue, nitrile rubber, full face gasket designed to
be used with water systems.
7. Bolts and Nutsing For Buried Flanged Joints: Bolting for buried flanged joints shall be Type
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 11
304 stainless steel, Grade B8 Hex Head bolts with Grade B8M Hex Head nuts, and shall
comply with all requirements of ASTM A193 and A194, respectively. Nuts shall be 304
stainless steel.
8. Gaskets for Flanged Joints: Gaskets for flanged joints shall be 1/8” full face gasket designed
to be used with water system, conforming to AWWA C207 and NSF 61 standards. Gasket
shall be US Pipe Full Face Flange-Typte gasket. Gaskets by other manufacturers need
approval by the Engineer. 1/8” thick cloth inserted rubber, one-piece, full-face type,
conforming to AWWA C207. For gasket installation requirements in contaminated areas, see
Section 2.10 02 of this Specification.
9. Flexible Restraint Devices: Electrofusion HDPE pipe flex restraint device, encased in
concrete, shall be attached to HDPE pipe near all transition connections to prevent pull out of
HDPE pipe and/or movement of existing pipe. Flex restraint device shall be ISCO Georg
Fischer Central Plastics or approved equal, designed for installation after a pipe is in place,
and be rated at min. 7000 lbs of force per fitting. Resin used to make this fitting shall meet
the requirements of ASTM 3350 with a cell classification of 345464C.
The electrofusion HDPE pipe flex restraints shall be installed in accordance with
manufacturer’s recommendations. Approximate Poisson effect pull force (Ib.), calculated per
AWWA M55 manual, for selected sizes of ANSI/AWWA C906 pipe operated at full rated
pressure, plus maximum allowable occasional surge pressure as follows:
Pipe size
(in.)
Approximate Pull Force
(lb)
Calculated Number of Flex
Restraints (each)
6 7,553 2
8 13,428 2
10 20,981 3
12 30,213 5
14 41,124 6
16 53,712 8
The Thrust Block Table and Valve Tie-Back Detail (Standard Details WD-13 and WD-18)
shall be used to size concrete encasement.
F. Service Hardware and Appurtenances: All hardware must be ANSI/NSF 61 listed.
1. HDPE Water Main Connection
a. HDPE Service: Service saddle shall be electrofusion IPS, HDPE 4710, Class 200
Electrofusion Branch Saddle manufactured by Georg Fischer Central Plastics, SA
Branch Saddle manufactured by Friatec, IntegriFuse manufactured by Integrity, or
approved equal. The fitting shall be NSF Standard 61 listed and meet or exceed
ANSI/AWWA applicable requirements. Pneumatic top-loading tool is required for proper
installation. Alternate installation methods may be used with prior approval from the City
Engineer.
b. Ball Valve (HDPE Service): Ball valve shall be 2” IPS DR 911, HDPE 4710 Class 200
Poly-Water Valve Full Port Polyethylene Ball Valve manufactured by Polyvalve Georg
Fischer Central Plastics, or approved equal.
c. Copper Service: Service Saddle shall be electrofusion IPS, HDPE 4710, Class 200
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 12
Electrofusion Branch Saddle manufactured by Georg Fischer Central Plastics, VA
Branch Saddle manufactured by Friatec, IntegriFuse manufactured by Integrity, or
approved equal, with brass 360 Alloy outlets and Stainless 304 compression rings. The
fittings shall be NSF Standard 61 listed and meet or exceed ANSI/AWWA applicable
requirements. Pneumatic top-loading tool is required for proper installation. Alternate
installation methods may be used with prior approval from the City Engineer. The fittings’
outlets shall be designed for AWWA straight iron pipe thread.
d. Flare Nut Transition (Copper Service): Flare nut transition shall be Poly–Cam Series 914
female swivel flare nut, lead free, transition designed for connecting 2” IPS HDPE 4710
potable water services directly to Mueller angle meter stops H-14255N (1” and smaller)
or H-24277N (1-1/2” and larger), and 2” Mueller corporation stops B-25025N, or
approved equal.
The HDPE portion of the transition fitting shall be HDPE 4710 SDR 9, IPS size
conforming to the latest edition of ANSI/AWWA C906, and have legible marking
indicating word “Water”, type of material (HDPE 4710), cell classification 445574C,
ANSI/AWWA C906, the manufacturer’s name or trademark, IPS size, OD, SDR, resin
supplier identification, and year of manufacture. All flare nut transition fittings shall
conform to NSF 61 standards.
e. Corporation Stops (Copper Service): Corporation Stops for connection to non-HDPE
mains shall be Mueller B-25000N or AY McDonald 74701B with AWWA taper thread and
copper flare straight connection outlets, or approved equal.
f. Three Part Unions (Copper Service): Three part unions shall be Mueller H-15400 with
copper flare nut on both ends, or approved equal.
2. Non-HDPE Water Main Connection (DIP, ACP, or PVC C-900 main/copper services):
Services Saddle shall be Class 200 NSF 61 listed Mueller BR2B bronze series with double
strap, or approved equal.
3. Angle Meter Stop: Angle meter stop shall be AY McDonald 74602B (FLR x Meter) for 1” and
smaller services and AY McDonald 74602B (FLR x Oval Flange) for 1-1/2” and 2” services,
or approved equal.
4. Ball Straight Meter Valve: Ball straight meter valve shall be Mueller B-20287N, or approved
equal.
5. Meter Boxes: Meter boxes shall be supplied by the Contractor when box replacement is
required or a new service is installed. The boxes shall be the following sizes:
Armorcast 11” x 21” x 12” Polymer Concrete Box (Part No. A6000492), Cover (Part No.
A6000489T-H7), Assembly with Drop-In Lid (Part No. A6000487T) and Plug (Part No.
A60000H7-PLUG-CPA)for 5/8”, 3/4" or 1” meters (Box Assembly Part No.
A6000492TACPA).
Armorcast 17” x 30” x 12” Polymer Concrete Box (Part No. A6001640PCX12), Cover (Part
No. A6001947TDZ), Assembly with Drop-In Lid (Part No. A6000482T-H7) and Plug (Part No.
A60000H7-PLUG-CPA) for 5/8” meters with 3/4" double headers (Box Assembly Part No.
A6001640TAPCX12CPA).
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 13
Armorcast 24” x 36” x 12” Polymer Concrete Box (Part No. A6001974PCX12), Cover (Part
No. A6001975TDZ), Assembly with Drop-In Lid (Part No. A6000482T-H7), and Plug (Part
No. A60000H7-PLUG-CPA) for 1” meters with 1” double headers (Box Assembly Part No.
A6001974TAPCX12CPA).
Armorcast 30” x 48” x 18” Polymer Concrete Box (Part No. A6001430PCX18), two (2)
Covers (Part No. A6001470TDZ) with two (2) Drop-In Lids (Part No. A6000482T-H7) and two
(2) Plugs (Part No. A60000H7-PLUG-CPA) for 1” quadruple headers and 1-1/2” and 2”
double and triple headers (Box Assembly Part No. A6001430TAPCX18CPA).
Armorcast 48”x96”x48” Polymer Concrete Vault with three (3) piece cover and two plugs for
4” and 6” water meter sets with 2” by-pass, and where combination fire/domestic water
services are installed (Box Assembly Part No. A6001449TAPCAX48CPA. Oldcastle
Precast/Christy B48 Box with two (2) self-closing, reading lids may also be used, as needed,
if approved by the Engineer.
Box assemblies include box, covers, reading lids, and plugs. Box and lid shall have a
minimum 20K rating (Tier 22) for all applications. Meter boxes shall not be installed in driving
lanes of public or private streets. Lids shall have “Water” marked on them and magnet
imbedded in cover.
All new water meter boxes shall be installed at standard depth (water meters shall be
installed at a depth of 10” from existing grade to the center of the meter per City standard
details). No additional extensions will be allowed to accommodate existing deep meters. If a
meter is found to be deeper than the standard 10”, Contractor will be required to raise the
meter to the standard depth of 10”.
G. Fire Hydrant Assemblies: Fire Hydrant assemblies shall use wet barrel type hydrants meeting
AWWA C503 standards. The fire hydrant assemblies shall be constructed using the following
materials:
1. Hydrants: Hydrants shall be AVK Series 24 Wet Barrel Hydrant in residential, commercial,
and heavy industrial areas. Any other hydrant manufacturer such as Clow or equal must
receive prior approval. AVK Series 24 Wet Barrel Hydrant shall be supplied with two (2) 2-
1/2” and one (1) 4-1/2” outlets conforming to AWWA C503, and shall be painted Safety
Yellow.
2. Hydrant Risers: Hydrant Risers shall be AVK Series 24/88X Flowguard II Hydrant Check
Valve conforming to the latest edition of ANSI C110/A21.10 standards and AWWA C503,
and as shown on WGW Utility Standards detail drawing WD-15.
3. Hydrant Bury: Hydrant Bury shall be 6” mechanical joint ductile iron conforming to the latest
edition of ANSI C110/A21.10 standards and AWWA C503, and as shown on WGW Utility
Standards detail drawing WD-15.
4. Hydrant Valves Locations: Hydrant valves shall be placed as close as practical to the water
main. For information on hydrant valves, see Section 2.01A.8 of this Specification.
5. Hydrant Valve Boxes: Hydrant Valve Boxes shall be Oldcastle Precast/Christy G05TBox
Traffic Valve Box with G05CT non-locking type metal traffic lid marked “Water”. Valve box
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 14
risers shall be solid 8” C-900 PVC pipe (Pressure Class 200) as shown on WGW Utility
Standard Detail WD-19.
H. Gate Valves (Hydrants and Mains):
1. 12” or Smaller (Installed with New HDPE Main): Gate valves 12” or smaller that are installed
on HDPE pipe shall be 250 psi, ductile iron ASTM A536 body, resilient-seated, tight closure
gate valves with non-rising stems, and have IPS HDPE 4710 DR 11 polyethylene pipe ends.
The valve shall be NSF 61 listed and meet or exceed AWWA C515 applicable requirements.
All gate valves shall have protective interior/exterior electrostatically applied fusion bonded
epoxy-resin coating in accordance with AWWA C550 requirements, stainless steel A2-Grade
304 bonnet and stuffing box bolts, and shall open counter clockwise. All gate valves shall be
American AVK 66/EEN (PE x PE), or approved equal.
2. 12” or smaller (Installed on Existing Non-HDPE Main): Gate valves 12” or smaller that are
installed on non-HDPE pipe shall be 250 psi, ductile iron ASTM A536 body, resilient wedge
gate valves with four point wedging mechanism, EPDM discs and O-rings, and non-rising
stems. The valve shall be NSF 61 listed and meet or exceed AWWA C515 applicable
requirements. All gate valves shall have protective interior/exterior fusion epoxy coating in
accordance with AWWA C550 requirements, and shall open counter clockwise. All bonnet
and stuffing box bolts shall be stainless steel 316. Valves shall have flange joint ends (FL x
FL), mechanical joint ends (MJ x MJ), or both flange and mechanical joint ends (FL x MJ).
Joints shall be in accordance with ANSI/AWWA C110/A21.10 (FL) and ANSW/AWWA C111
(MJ) requirements, as applicable. All gate valves shall be Mueller A-2361 Series, or
approved equal.
3. 14” or Larger: Gate valves 14” or larger shall be 250 psi, ductile iron ASTM A536 body,
resilient wedge gate valves with four-point wedging mechanism, EPDM discs and O-rings,
and non-rising stems. The valve shall be NSF 61 listed and meet or exceed AWWA C515
applicable requirements. All gate valves shall have protective interior/exterior fusion epoxy
coating in accordance with AWWA C550 requirements, and shall open counter clockwise. All
bonnet and stuffing box bolts shall be stainless steel 316. Valves shall have flange joint ends
(FL x FL), mechanical joint ends (MJ x MJ), or both flange and mechanical joint ends (FL x
MJ). Joints shall be in accordance with ANSI/AWWA C110/A21.10 (FL) and ANSW/AWWA
C111 (MJ) requirements, as applicable. All gate valves shall be Mueller A-2361 Series, or
approved equal.
I. Butterfly Valves (Transmission Mains):
Butterfly valves shall 250 psi rated, with ductile iron body conforming with ASTM 536 standards.
The valve shall be NSF 61 certified and shall meet requirements of ANSI/AWWA C504 Standard
Class 250B. The valve shall have ductile iron disc conforming with ASTM 536 standards. The
valve shall have seat-in-body design and nonmetallic bearings. All butterfly valves shall be
coated in accordance with AWWA C550 and C504 standards. All valve hardware shall be 304
stainless steel. Butterfly valves shall have a 2” bypass per Standard Detail WD-14. All butterfly
valves shall be Mueller, Lineseal Series or approved equal.
J. Valve Stem Extensions: Valve stem extensions shall be fusion coated and furnished with an
AWWA brass wrench; top of AWWA brass wrench nut not to exceed two (2) feet below finished
grade. The valve stem extension shall have a six inch (6”) diameter, ¼-inch thick, fusion-coated
black iron guide plate welded six inches (6”) below the AWWA brass wrench nut. Stem
extensions are to be installed on valves four (4) feet and greater in depth.
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 15
K. Valve Boxes: Valve boxes shall be Oldcastle Precast/Christy G05TBox Traffic Valve Box with
G05CT non-locking type metal traffic lid marked “Water”. Valve box risers shall be corrugated 8”
HDPE (smooth inner pipe). The riser outside diameter shall be between 9.0” to 9.4” and closely
match the valve box inside diameter at the point of insertion. See WGW Utility Standard Detail
WD-14.
L. Air Release and Air/Vacuum Valves:
1. Air Release Valves: Air release valves shall be APCO, Crispin-Multiplex Mfg. Co., or
approved equal, and shall conform to the latest edition of AWWA C512. For 8” through 12”
HDPE mains, air valve assemblies shall be a minimum of 1”, and for 14” and larger HDPE
mains, air valves assemblies shall be a minimum of 2”. All assemblies shall have stainless
steel floats.
2. Air/Vacuum Valves: Air/Vacuum valves shall be APCO, Crispin-Multiplex Mfg. Co., or
approved equal, and shall conform to the latest edition of AWWA C512. For up to 10” HDPE
mains, air/vacuum valve assemblies shall be a minimum of 1”, and for 12” and larger HDPE
mains, air/vacuum assemblies shall be a minimum of 2”. All assemblies shall have stainless
steel floats. Air Release/Vacuum valve vents shall be placed above flood plain.
M. Line Stopping:
Line stopping is used when existing distribution valves do not exist, have failed, or if line stops
are called out on the plans. The line stopping shall be performed following written approval of
the engineer. All line stopping equipment must be disinfected prior to use per ANSI/AWWA
C651/B301. Line stop types shall be utilized in the following order:
1. Permanent Insertion Valves (for pipes with smooth interior walls): valve box and operational
permanent insertion valve line stops shall be installed similar to a gate valve for future
operability. Insertion valves shall be class 250. Insertion valves shall be Insta-ValveTM by
Hydra-Stop, or an approved equal.
2. Temporary Internal Line Stops (for all pipe types): Saddles shall be bolted with stainless
steel bodies and components. Saddles shall be class 250 and compatible with the main
(asbestos cement, PVC, ductile iron, or cast iron pipe, fused (HDPE) or welded (concrete
cylinder pipe)) and line stop equipment. Saddles shall be manufactured by Hydra-Stop, JCM
or an approved equal.
3. HDPE Squeezing: HDPE pipe, up to 8” diameter and not exceeding an operating pressure
of 100psig, may be squeezed-off per the manufacturer’s recommended procedures.
Squeeze-off tools shall be designed for use on HDPE pipe in accordance with AWWA
F1563. The tools and procedures shall be approved by the City prior to use. Squeeze-off
tool shall be manufactured by Footage or an approved equal.
N. Thrust Blocks:
Thrust blocks shall be Class B Portland cement concrete, Type II, meeting Caltrans Standard
Specification Section 90 requirements and sized according to the detail shown on the WGW
Utility Standard Detail WD-13.
O. Shell Cutter:
Shell cutters shall be Mueller, or approved equal, for tapping HDPE 4710, C900 PVC, asbestos
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 16
cement (AC), ductile iron (DI), or cast iron (CI) pipe. A shell cutter for both plastic pipe and/or
AC/DI/CI pipe shall be approved by the engineer prior to use. Shell cutters shall be tungsten
carbide tipped, designed for an easy fit through valves, and shall have large slots for debris
removal. "Drill-bit" type cutters shall not be used.
P. Tracer Wire and Connections:
Tracer wire shall be Agave Wire, LTD 10 AWG solid copper wires coated with .45 mils Type
HMW - PE insulated conductor, blue in color, or approved equal. The wire shall meet all
requirements of the latest version of ASTM D1351 and ASTM B8 and shall be UL listed as direct
burial wire for temperatures between -20o C and 80o C for circuits not exceeding 600 volts. The
surface of the insulation shall be durably marked, at intervals not exceeding 24 inches, with only
the following information: maximum working voltage "600 VOLTS", wire type, manufacturer's
name or trademark, AWG size, and UL required markings. Tracer wire shall be installed on all
HDPE pipe mains and services.
One tracer wire shall be installed with the pipe. All tracer wire connections shall be made using
the Nicotap connector system T1-102-D, wrapped with aqua seal and electrical tape. All Nicotap
fittings must be installed with tooling specified by the manufacturer. The use of pliers or other
crimping devices will not be allowed.
Anode boxes, and 5 to 10 lb. Mg anode bags (provided by City), shall be installed at fire hydrants
as directed by the City, with tracer wire extending as shown on WGW Utility Standard Detail WD-
15. For single service installations that are not part of a Capital Improvement Project, anode
boxes, and 1 lb. Mg anode bags (provided by City), shall be installed at water meter, with tracer
wire extending as shown on corresponding WGW Utility Standard Details. The wire configuration
shall be as follows: North tracer wire – terminal 1, no knot, East tracer wire – terminal 2, with one
knot, South tracer wire – terminal 3, with two knots, and West tracer wire – terminal 4, with three
knots.
Q. Warning Tape:
Warning tape shall be Northtown Pipe Protection Products Hytech Non-Detectable Tape, or
approved equal, 3 inches wide, blue and carry the inscription: “Caution Buried Water Line
Below”. Warning tape shall be installed 12 inches above the top of the new water main (initial
backfill zone).
R. Anode Boxes:
Anode boxes shall be Oldcastle Precast/Christy G05TBox Traffic Valve Box with G05CT non-
locking type metal lid marked “Anode Water”.
4.02 MANUFACTURER'S TESTING
A. Health effects evaluation:
All materials in direct contact with potable water, including but not limited to, pipe and fittings
must comply with ANSI/NSF Standard 61.
B. Long-term hydrostatic strength:
Materials must be tested to establish that their minimum long-term hydrostatic strength is in
compliance with the requirements of the applicable AWWA product standard (AWWA C906).
C. Material cell classification:
PE materials must have a cell classification 445574C per ASTM D3350.
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 17
4.03 SUBMITTALS AND QUALITY CONTROL
A. The Manufacturer shall submit a written quality control procedure conforming to requirements of
ANSI/AWWA C901 (up to 4”) and C906 (4” and larger), which shall be subject to approval by
engineer.
B. The Manufacturer shall permit City representatives to tour extrusion facilities for the purpose of
evaluating manufacturer's capabilities. The tour shall be during extrusion of a City order or if prior
to order placement during the extrusion of a similar material.
C. The Manufacturer shall certify that the plastic pipe and or fittings supplied meet all the
requirements of this Specification. When requested by the City, the Manufacturer shall supply
certification for all items ordered. Failure to do so shall be cause for order rejection.
4.04 MATERIAL INSPECTION
City reserves the right to inspect all material and may reject any items not meeting these
Specifications.
PART 5 - EXECUTION
5.01 HDPE WATER MAIN SYSTEM INSTALLATION
A. Valve Boxes/Valve Pits:
Main line valve boxes shall be installed per Section 4.01A.16 of this Specification.
B. Line Stopping:
1. Internal Line Stops (All pipe types): In order to minimize potential traffic hazards, all
excavation and necessary preparation, prior to line stopping and new line valve installation,
shall be done one (1) day in advance prior to the actual plumbing work. Each line valve
installation shall include two (2) line stops, one upstream and one downstream of the line
valve to be replaced, complete with all necessary equipment (i.e., bypass, sawcutters,
backhoes, deck plates, traffic control, etc.) and materials (i.e., piping, disinfectant, couplings,
concrete, AC, backfill, restraint, etc.), needed to assemble and complete installation of the
new line valve.
2. HDPE Squeezing: Squeezing and releasing rates are key elements in squeezing off HDPE
correctly. Squeeze pipe slowly to close, no faster than 2 inches per minute (2ipm) based on
the pipelines outside dimension, release squeeze tool at a rate, no faster than 0.5ipm based
on the pipelines outside dimension, and allow the pipe to naturally rebound. Do not squeeze-
off pipe within 12” or 3x the pipe diameter, whichever is greater, from other fittings or
previous squeezes. After squeeze-off is complete wrap vinyl tape at the squeeze off location
to 6 inches on each side and mark the pipe “Squeeze Off” for future reference.
C. Main Filling:
All main filling shall be done in the presence of the Engineer and/or field inspector, and field
operations personnel. Corporation stops shall be installed on the main so as to remove trapped
air prior to pressure testing.
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 18
D. Maximum Pull Force:
A commercially available weak link approved by the Engineer shall be used, in accordance with
manufacturer’s recommendations, between the puller and the pipe during directional drilling
operations. See Section 2300 for maximum allowable pull force for PE 4710 HDPE.
5.02 HDPE WATER SERVICE INSTALLATION
Transfer or reconnection of a water service from the existing main to a new main may cause an
interruption in the customer's service. The contractor must notify the customer via door hanger
notices, 24 hours in advance of the service interruption with the approximate time (8 am -12 pm or 1
pm - 5 pm) and duration of the service interruption. At the time of service interruption, the customer
shall be notified by ringing the door bell or knocking. The customer's main water valve will be closed if
it can be located. After the service has been transferred/reconnected the customer's main water valve
will be opened, and customer's service pipe flushed through a hose bib to remove air, sand, chlorine,
shaving material, etc.
5.03 WATER METER REPLACEMENT
A. Work Materials to be Furnished by the City: The City will provide new water meters for
replacement where designated by the engineer. All other materials shall be provided by the
Contractor. All meters to be obtained from the City of Palo Alto Water Operations Department.
B. Work Materials to be Furnished by the Contractor shall include, but are not limited to:
1. All materials and equipment needed to complete installation of new HDPE mains, services,
and small/large meter vaults including by-passes.
2. Expendable Concrete Materials: Materials required to install and finish Portland cement
concrete, such as form lumber, tie-wire, nails, etc.
3. Concrete: All Portland cement concrete including reinforcing steel, wire mesh, etc.
4. Temporary and Permanent Fencing: All fencing including traffic barricades required to
provide a barrier between vehicular/pedestrian movements and excavations.
5. Trench Backfill Sand: All backfill sand shall be clean, imported sand, rock and salt free. Bay
sand will not be accepted.
6. Paving Material: All materials required for temporary and permanent street repairs including
base materials.
7. Landscaping Materials: All landscaping materials, plants and surface materials that are
damaged due to Work.
8. Traffic Control Materials: All materials required to direct vehicular/pedestrian traffic, including
striping, loop detectors, reflectors, etc. that may be damaged by the Work.
9. Drilling fluids and bentonite for directional drilling operations.
10. Non-skid trench plates.
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 19
11. Project notification signs.
5.04 HDPE HYDRANT ASSEMBLIES AND FIRE SERVICES
Hydrant Assemblies shall be installed and field tested according to the requirements of AWWA M17,
ANSI/AWWA C503, and as shown on the Project Drawings.
Prior to reconnection, all existing fire services shall be potholed by the Contractor to avoid possible
conflicts. Existing fire service pipe shall be joined with new HDPE pipe, connected to a new HDPE
water main by MJ adapter, or as shown on the WGW Utility Standard Details. Contractor may be
required to furnish shop drawings of how re-connection will be constructed and shall inform the
nearest City Fire Station, City Communications Center, and Customers regarding the fire service
work. The Contractor will be required to make all necessary schedule arrangements to accommodate
the customer's needs.
5.05 Testing and Inspection
The Engineer or Inspector shall have access to the Work area at all times, and the Contractor shall
provide proper facilities for such access and inspection. If the Specifications, the Engineer's
instructions, law, ordinances, or any other public authority require any work to be specially tested or
approved, the Contractor shall give the Engineer 24-hour notice of its readiness for inspection. If the
inspection is by an authority other than the Engineer, the Contractor shall make special arrangements
for the outside authority to make its inspection. Work covered up without approval or consent of the
Engineer or Inspector, shall, if required by the Engineer or Inspector, be uncovered for examination
and properly restored at the Contractor's expense.
Authorized Inspectors are considered to be representatives of the City, limited to the duties and
powers entrusted to them. It will be the Inspectors' duty to inspect materials and workmanship of
those portions of the Work to which they are assigned, either individually or collectively, under the
instructions of the Engineer, and to report any and all deviations from the Project Drawings,
Specifications and other Contract provisions which may come to their notice. An Inspector will order
the Work entrusted to his/her supervision stopped if in his opinion such action becomes necessary.
The Engineer will be notified and will determine if the Work is proceeding in due fulfillment of all
Contract requirements.
All pipe and accessories shall be laid, jointed and tested under pressure for defects and leakage the
manner specified, in the presence of and as approved by the Engineer or Inspector.
A. Connection to Existing Main: The Contractor shall make connections to existing mains where
indicated on the Drawings. All necessary preparation (not limiting to traffic control and
excavation) for system connections shall be done one (1) day prior to actual materials
installation. All new water mains shall be kept isolated from the City system until they are
flushed, bacteriologically tested, and accepted. New system isolation by a closed valve
will not be permitted. The Engineer will review the Contractor's method and sequence of
connecting to existing mains to minimize contamination danger. Connections to existing valves
prior to obtaining satisfactory leakage and pressure tests of the new facilities will not be allowed.
The City assumes no responsibility for the water tightness of existing valves. If necessary, the
Contractor must work with the City to accomplish water tightness. All costs and expenses for
obtaining water tightness shall be included in the bid price for various bid items, and no special
compensation shall be allowed.
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 20
Service interruptions on existing mains impacted by a shutdown shall be coordinated with the
Engineer, who will specify time and duration of the interruption. The Contractor shall notify all
affected users in writing at least 48 hours in advance of service interruption. The Contractor shall
notify the City's Water-Gas-Wastewater Operations Division (496-6967) at least 5 days in
advance to schedule valve closures for service interruptions. Manipulation of existing valves
shall only be done by or under the direction of City Water Division personnel.
After the new water system has been flushed, bacteriologically accepted, pressure and leak
tested, and placed into service, all valves in the system shall be maintained in an "on" position
unless otherwise directed by the Engineer.
B. Hydrostatic Pressure and Leak Testing: Installed main shall be adequately anchored with a
covering of at least 6” of initial backfill, if installed by open trench method. The joints and fittings,
particularly flange connections, shall be left uncovered for visual leak inspection.
Leak tests of the new HDPE water system shall be conducted in accordance with ASTM F2164.
The pipeline should be slowly filled with potable water and all trapped air bled off. The main
should undergo a hydrostatic pressure test using a pressure of 150 psi. The pressure shall be
maintained constant for a 4-hour period by adding makeup water. After 4 hour period is
completed, the pressure shall remain steady within 5% (7.5 psi) of a target 150 psi test pressure
for one hour. The total test time should not exceed 8 hours. If the pipeline has to be retested –
the pipe must be depressurized and allowed to “relax” for at least 8 hour period before the next
testing sequence.
In fused polyethylene water piping system, no leakage shall be present. If leakage is observed at
a fusion joint, complete rupture may be imminent. The Contractor shall move all personnel away
from the joint and depressurize the main. Leaks, failure, or defective construction shall be
promptly repaired by the Contractor, at the Contractor’s sole expense. Payment for pressure and
leakage testing shall be considered included in the price paid per linear foot for water main
installation.
C. Disinfection and Bacteriological Testing: Newly installed potable water pipelines (mains and
services) require disinfection in accordance with ANSI/AWWA C651/B301. Disinfection shall take
place after the initial flushing, and after the completion of the pressure testing. Individual new
water services will be flushed through the angle meter stop after connection to the new water
main. The new pipe, connections, and fittings must be kept clean and swabbed with a 5%
solution of hypochlorite before installation.
Injection of liquid chlorine solution shall be used to disinfect HDPE water pipes. With this method,
the main is filled to remove air pockets and chlorine is injected continuously until a concentration
between 25mg/L and 50 mg/L is obtained throughout the main. The chlorinated water in all
portions of the main shall have a residual of not less than 10 mg/L of free chlorine after a 24-hour
period. Contractor shall note that prolonged exposure to highly concentrated disinfection
chemicals may damage the inside surface of HDPE pipe and shall be avoided. Air is to be
exhausted from each high point, dead end, branch run and hydrant run. The chlorinated water
shall be removed prior to samples being collected for bacteriological testing.
Before bacteriological testing samples are taken, each hydrant run, branch run and dead end
shall be thoroughly flushed to clear highly chlorinated water and until the residual chlorine
concentration reaches normal distribution system levels. If discharging to storm drainage system,
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 21
Contractor shall first obtain approval from the City. The Contractor shall measure residual
chlorine concentrations by using a color comparator test that is witnessed and approved by the
Inspector. Samples shall be gathered and tests conducted according to the provisions of AWWA
C651-14, at the expense of the Contractor, by a laboratory approved by the Engineer. Samples
shall be taken at representative points as required to thoroughly test the installed pipe. Fire
hoses and fire hydrants shall not be used to gather samples. The Contractor will be required to
perform two consecutive Coliform tests at a minimum of 16-hours apart. The testing laboratory
used by the Contractor shall be State Certified and provide QA/QC reports.
The new facilities shall remain isolated and out of service until satisfactory test results have been
obtained that meet the requirements of the State Water Resource Control Board, and the
Engineer has accepted the results as indicative of the bacteriological condition of the new water
pipe. If unsatisfactory or doubtful results are obtained from the initial sampling, the pipe (mains
and services) shall be flushed and the chlorination process shall be repeated until acceptable
test results are obtained. The bacteriological test takes at least 48 hours for results to be
conclusive.
Disposal of chlorinated water shall comply with all federal, state, and local regulatory
requirements. Disposal directly to the storm drain system without removal of chlorine is strictly
prohibited. No discharge into the storm drain system shall be allowed during rain. Upon
termination of the flushing, any standing water in the gutter shall be removed by sweeping it to
the nearest storm drain catch basin or sewer manhole. Flushing of chlorinated water directly into
the sanitary sewer system will only be allowed with Engineer’s approval.
If new water mains will not be tied into the water distribution system within 72 hours following the
Engineer’s acceptance of the bacteriological test results, Contractor may be required to flush the
highly chlorinated water from the main, refill the main with potable water, and maintain pressure
in the main until the tie-in is complete. If the main is allowed to sit empty for a period longer than
24 hours, the Contractor will be required to repeat flushing, disinfection and bacteriological
testing procedures at the Contractor’s expense.
D. Washing/Flushing Vehicles: All vehicles used for street washing or flushing must be equipped
with meters and have air gap separation connections to hydrants and filling tanks.
5.06 Water Service Abandonment Procedure
A. Excavate existing water service at the main.
B. Service with a corporation stop and service saddle: turn off corporation stop and check for leaks.
Cut the copper or HDPE tubing with a tubing cutter and bend both cut ends over approximately
1" from cut end (copper service) or electrofuse HDPE electro fusion end cap (HDPE service).
C. Service with a corporation stop with no service saddle: notify and coordinate with all affected
Customers, along with City Utility Operations staff, of the pending service interruption. Remove
corporation stop and install a Mueller or Ford repair clamp. Any leaks, failures, or defective
repairs shall be promptly repaired by the contractor.
D. Remove water meter and salvage to the City of Palo Alto corporation yard water meter repair
shop.
E. Remove abandoned water meter vault. Backfill and compact hole to City standards with top soil
WATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2660
CITY OF PALO ALTO Section 2660 PAGE 22
or clay dirt.
F. Backfill, compact and pave hole at the main per WGW Utility Standard Detail WGW-02.
G. Abandonment of all existing water services shall be witnessed by the City’s Utilities Inspector.
Schedule WGW utilities inspections at 650/566-4501 five working days before start of
abandonment.
5.07 Procedure for Disconnecting Large Service with Tapping Tee and Valve
A. Provide a 72-hour notification of service interruption to all affected water customers. Coordinate
water shutdown with affected customers and Utilities Engineering/Operations staff. The
shutdown plan must be approved by the City prior to shutting down the water service.
B. Shut down the main and excavate existing fire hydrant or service at the main.
C. For hydrant service or water service with tapping saddle, remove the tapping saddle and install a
Mueller repair clamp. Any leaks, failures, or defective repairs shall be promptly repaired by the
contractor.
D. For service with a tee, remove the tee and replace the section with HDPE or PVC C-900 straight
pipe. Use fully-restrained mechanical couplings for straight pipe connections to existing non-
HDPE pipe. Couplings model and manufacturer shall be approved by City.
5.08 ACP Pipe and Hazardous Material Disposal
Asbestos containing pipe must be properly disposed of per State and Federal regulations. Contractor
and subcontractors, if any, shall be in full compliance with any and all laws, orders, citations, rules,
regulations, standings and statutes in effect with respect to handling, storage and removal of
Hazardous Material. Contractor accepts sole responsibility for insuring the adequacy of any required
use of all safety practices, procedures and equipment.
END OF SECTION
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 1
SECTION 2685
NATURAL GAS DISTRIBUTION SYSTEM
PART 1 - GENERAL
1.01 DESCRIPTION
Work includes installation of natural gas mains, natural gas services, tracer wire, polyethylene valves
and boxes, polyethylene fittings, excess flow valves, anode boxes, modification of existing natural
gas house plumbing to accommodate relocation of gas meters, and all related equipment and fittings
in accordance with the requirements of the Contract Documents.
1.02 RELATED WORK
A. Section 2200: Excavation, Backfill, and Restoration
B. Section 2300: Polyethylene Pipe Installation for Water, Gas, and Wastewater
1.03 QUALIFICATION OF NATURAL GAS DISTRIBUTION SYSTEM CONTRACTOR
The Contractor performing work on the City of Palo Alto natural gas distribution system shall have
and must submit for approval by the City of Palo Alto a drug-testing program in place per Pipeline
Safety Regulations Part 199 "Drug Testing Pipeline Safety" and Part 40 "Procedures for
Transporting Workplace Drug and Alcohol Testing Programs" and Management Information
Sheets for each year requested by the City Project Manager.
PART 2 - MATERIALS
2.01 NATURAL GAS DISTRIBUTION SYSTEM MATERIALS
A. POLYETHYLENE PIPE: Polyethylene pipe supplied under this section shall be in compliance
with ASTM D2513-09a “Standard Specification for Polyethylene (PE) Gas Pressure Pipe, Tubing
and Fittings”, incorporated by reference into Code of Federal Regulations (CFR) Title 49, Part
192.7 and specifications stated herein:
1. All pipe shall be Medium Density Polyethylene (MDPE) 2708 pipe, uniformly yellow in color,
conforming to the latest edition of ASTM D3350 “Standard Specification for Polyethylene
Plastics Pipe and Fittings Materials”, cell classification 234373E. extruded from one of the
following: Performance Pipe Company Marlex HHM TR-418Q Resin or Ineos Fortiflex® K38-
20-160 Resin.
a. In special circumstances and upon approval, High Density Polyethylene (HDPE) 4710
pipe, uniformly black in color with four (4) equally placed stripes, conforming to the latest
edition of ASTM D3350 “Standard Specification for Polyethylene Plastics Pipe and
Fittings Materials”, cell classification 445574C, may be used.
2. Pipe dimensions and tolerances: The outside diameter and wall thickness shall be within
the limits specified in Table 1 for MDPE pipe.
3. Markings: All pipe markings for gas pipe shall be in compliance with the latest edition of
ASTM F2897 “Standard Specification for Tracking and Traceability Encoding System of
Natural Gas Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)”
and consist of a 16-digit alpha-numeric code and scannable code-128 barcode, or QR code,
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 2
with standardized encoding of pipe specifications as described in the referenced Standard. In
addition, gas pipe markings shall also comply with the marking requirements for all
polyethylene pipe specified in Section 2300 of these Specifications.
4. Approved Manufacturers: The City of Palo Alto approved PE pipe manufacturer is Chevron
Phillips Chemical Company (CP CHEM) Performance Pipe. Any other pipe manufacturer
such as JM Eagle or equal must receive prior approval.
Table 1: Dimensional Standards for Polyethylene Pipe and Tubing (Per ASTM D2513)
Nominal
Pipe/
Tubing
Size
Average
Outside
Diameter
(inches)
Outside
Diameter
Tolerance
(inches)
Minimum
Wall
Thickness
(inches)
Wall
Thickness
Tolerance
(inches)
Out of
Roundness
Tolerance
(inches)
Standard
Dimension
Ratio
(unitless)
1" CTS 1.125 ± 0.005 0.099 + 0.012
- 0.000
- -
2" IPS 2.375 ± 0.006 0.216 + 0.026
- 0.000
± 0.024 11.0
3” IPS 3.500 ± 0.008 0.304 + 0.036
- 0.000
± 0.030 11.5
4" IPS
4.500 ± 0.009 0.391 + 0.047
- 0.000
± 0.030 11.5
6" IPS
6.625 ± 0.011 0.576 + 0.069
- 0.000
± 0.070 11.5
8" IPS 8.625 ± 0.013 0.750 + 0.090
- 0.000
± 0.080 11.5
Note: 3” IPS PE pipe shall only be used for the repair of existing 3” PE pipe.
B. PE Fittings: All molded polyethylene fittings supplied under this section shall be in compliance
with ASTM D2513-09a “Standard Specification for Polyethylene (PE) Gas Pressure Pipe, Tubing
and Fittings”, incorporated by reference into CFR Title 49, Part 192.7 and ASTM D3261
“Standard Specification for Butt Heat Fusion Polyethylene (PE) Plastic Fittings for Polyethylene
(PE) Plastic Pipe and Tubing”, and specifications stated herein:
1. All fittings shall be Medium Density Polyethylene (MDPE) 2708 fittings, uniformly yellow in
color, conforming to the latest edition of ASTM D3350 “Standard Specification for
Polyethylene Plastics Pipe and Fittings Materials”, cell classification 234373E. molded from
one of the following: Performance Pipe Company Marlex HHM TR-418Q Resin; or Ineos
Fortiflex® K38-20-160 Resin.
a. In special circumstances and upon approval, High Density Polyethylene (HDPE) 4710
fittings, uniformly black in color, conforming to the latest edition of ASTM D3350
“Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”, cell
classification 445574C (Black), may be used.
2. Dimensions and tolerances: Butt Fusion Fittings shall conform to the dimensions given in
Table 2.
3. Approved Manufacturers: The City of Palo Alto approved PE fitting manufacturer is
Chevron Phillips Chemical Company (CP CHEM) Performance Pipe. Any other pipe
manufacturer such as CSR Poly Pipe Industries or equal must receive prior approval.
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 3
Table 2: Dimensional Standards for Polyethylene Butt Fusion Fittings
Nominal
Fitting
Size
Ave Outside
Dia at Point
of Fusion
(inches)
Outside
Diameter
Tolerance
(inches)
Minimum
Wall
Thickness
(inches)
SDR
(unitless)
Minimum
Stub
Length*
(inches)
2" IPS 2.375 ± 0.006 0.216 11.0 2.0
4" IPS 4.500 ± 0.009 0.391 11.5 3.0
6" IPS 6.625 ± 0.011 0.576 11.5 3.5
8" IPS 8.625 ± 0.025 0.750 11.5 3.5
* As defined in Figure 1 (only applicable to tees, 45° and 90° ells).
Figure 1: Definition of Stub Length for Butt Fusion Fittings
STUB LENGTH-S
S PORTIONS O.D. CONTROLLED
TO MATCH PIPE O.D.
C. Polyethylene Gas Valves: All polyethylene gas valves supplied under this section shall be in
compliance with ASTM D2513 “Standard Specification for Polyethylene (PE) Gas Pressure Pipe,
Tubing and Fittings”, CFR Title 49, Part 192.145 “Valves” and the latest editions of ANSI/ASME
B16.40 “Manually Operated Thermoplastic Gas Shutoffs and Valves in Gas Distribution
Systems”, and specifications stated herein:
1. The polyethylene portion of the gas valve shall be one-piece molded medium density PE
2708 polyethylene conforming to the latest edition of ASTM D3350 “Standard Specification
for Polyethylene Plastics Pipe and Fittings Materials”, cell classification 234373E
manufactured from Performance Pipe Company Marlex HHM TR-418Q Resin, Rigidex PC
2040Y, or FINATHENE 3802Y.
2. All polyethylene gas valves shall be manufactured within 6 months from the date of sale to
the City.
3. All polyethylene gas valves shall be full port, assembled to operate smoothly and provide a
gas tight seal(s). Polyethylene gas valves shall utilize a 2” square operating nut with positive
position indication and over-torque protection actuator. Each valve’s stem shall be equipped
with weather seal(s) protecting inner parts from ground water and foreign debris intrusion. All
polyethylene valves shall be supplied with the butt end outlets.
4. For purging at designated locations, Flowserve Corp. (Nordstrom Valves) with integral
polyethylene purge connections shall be used. These valves shall comply with all
specifications for polyethylene gas valves of this section.
5. Markings: Polyethylene gas valve markings shall be in compliance with the latest edition of
ASTM F2897 “Standard Specification for Tracking and Traceability Encoding System of
Natural Gas Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)”
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 4
and consist of a 16-digit alpha-numeric code and scannable code-128 barcode, or QR code,
with standardized encoding of pipe specifications as described in the referenced Standard.
6. Approved Manufacturers: The City of Palo Alto approved PE gas valve manufacturer is
Flowserve Corp. Polyvalve Poly-Gas (Formally Nordstrom Valves). Any other pipe
manufacturer such as Kerotest Manufacturing Corp (PolyBall), or Broen, Inc. (Ballomax)CSR
Poly Pipe Industries or equal must receive prior approval.
Table 3: Dimensional Standards for Full Port Polyethylene Valves
VALVE SIZE SDR MIN. PORT DIA.* MIN. STUB LENGTH*
2" 11 1.82" 4.2"
4" 11.5 3.62" 3.1"
6" 11.5 5.20" 3.9"
8" 11.5 6.60" 7.0"
*as defined in Figure 2
Figure 2: Definition of Dimensions for Polyethylene Valves
D. Gas Service Riser (Anodeless): Risers must meet or exceed the latest editions of the following
standards or requirements:
x Department of Transportation (DOT) Code of Federal Regulations, Title 49, Part 192.
x ASTM D2513 “Standard Specification for Tracking and Traceability Encoding System of
Natural Gas Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)”
x ANSI B1.20.1 “Pipe Threads, General Purpose, Inch”, latest edition
x ASTM G8 “Standard Test Methods for Cathodic Disbonding of Pipeline Coatings”, latest
edition
x 100% factory leak tested
x Polyethylene pigtail markings shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of
a 16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with
standardized encoding of pipe specifications as described in the referenced Standard.
1. Prebent Risers:
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 5
a. Anodeless 1"PE CTS X ¾" MPT PREBENT: The 1" casing pipe shall be fabricated
from ASTM A53 schedule 40, Grade A steel pipe. The casing shall also conform to the
following requirements: gray fusion bonded epoxy coated (8 mil minimum thickness); 46
inches long, 1.500” OD x 0.075” wall thickness; ASTM A513 mechanical tubing with ¾"
MPT nipple outlet and neoprene bushing, crimped in place, moisture seal. Additionally,
the casing pipe shall be bent to a 12-inch minimum radius resulting in a min. 16"
horizontal by 30" vertical configuration.
A minimum 10-inch-long, 1" CTS (0.099 wall thickness) PE pigtail shall extend from the
steel pipe casing. The 1" CTS carrier pipe shall be medium density PE 2708
polyethylene, uniformly yellow in color, conforming to the latest edition of ASTM D3350
“Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”, cell
classification 234373E extruded from one of the following Performance Pipe Company
Marlex HHM TR-418Q Resin or Ineos Fortiflex® K38-20-160 Resin.
The transition from steel to PE shall occur within 6 inches of the threaded end. Risers
shall include insulation between the steel casing and the PE carrier pipe by means of an
o-ring/air space configuration or using a sleeve made of non-heat conducting materials.
All exposed threads and openings shall be covered with protective caps. The riser label
shall include manufacturers name, part number, lot number and casing pipe shall have
indication of ground level.
Anodeless risers must have approved meter valves included.
b. Anodeless 1"PE CTS X 1-1/4" MPT PREBENT: The 1-1/4" casing pipe shall be
fabricated from ASTM A53 Schedule 40, Grade A steel pipe. The casing shall also
conform to the following requirements: gray fusion bonded epoxy coated (8 mils
minimum thickness); 60 inches long, 1.625” O.D. x 0.072 wall thickness; ASTM A513
mechanical tubing with 1-1/4" MPT nipple outlet and neoprene bushing, crimped in
place, moisture seal. Additionally, the casing pipe shall be bent to a 12-inch minimum
radius resulting in a 30" horizontal by 30" vertical configuration.
A minimum 10-inch long, 1" CTS (0.099 wall thickness) PE pigtail shall extend from the
steel pipe casing. The 1” CTS carrier pipe shall be medium density PE 2708
polyethylene, uniformly yellow in color, conforming to the latest edition of ASTM D3350
“Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”, cell
classification 234373E extruded from one of the following: Performance Pipe Company
Marlex HHM TR-418Q Resin or Ineos Fortiflex® K38-20-160 Resin.
The transition from steel to PE shall occur within 6 inches of the threaded end. Risers
shall include insulation between the steel casing and the PE carrier pipe by means of an
o-ring/air space configuration or using a sleeve made of non-heat conducting materials.
All exposed threads and openings shall be covered with protective caps. The riser label
shall include manufacturers name, part number, lot number and casing pipe shall have
indication of ground level.
Anodeless risers must have approved meter valves included.
c. Anodeless 2"PE IPS X 2" MPT PREBENT: The 2" casing pipe shall be fabricated from
ASTM A53 Schedule 40, Grade A steel pipe. The casing shall also conform to the
following requirements: gray fusion bonded epoxy coated (8 mil minimum thickness); 72
inches long, 2" MPT nipple outlet and neoprene bushing, crimped in place, moisture
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 6
seal. Additionally, the casing pipe shall be bent to a 24-inch minimum radius resulting in
a 36" horizontal by 36" vertical configuration.
A minimum 10-inch long, 2" IPS (0.216 wall thickness) PE pigtail shall extend from the
steel pipe casing. The 2” IPS carrier pipe shall be medium density PE 2708
polyethylene, uniformly yellow in color, conforming to the latest edition of ASTM D3350
“Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”, cell
classification 234373E extruded from one of the following: Performance Pipe Company
Marlex HHM TR-418Q Resin or Ineos Fortiflex® K38-20-160 Resin; SDR 11.0.
The transition from steel to PE shall occur within 6.5 inches of the threaded end. Risers
shall include insulation between the steel casing and the PE carrier pipe by means of an
o-ring/air space configuration or using a sleeve made of non-heat conducting materials.
All exposed threads and openings shall be covered with protective caps. The riser label
shall include manufacturers name, part number, lot number and casing pipe shall have
indication of ground level.
Anodeless risers must have approved meter valves included.
2. Straight Risers:
a. Anodeless 1"PE CTS X ¾" MPT STRAIGHT - The ¾" casing pipe shall be fabricated
from ASTM A53 Schedule 40, Grade A steel pipe. The casing shall also conform to the
following requirements: gray fusion bonded epoxy coated (8 mils minimum thickness);
60 inches long, 1.500” OD x 0.072” wall thickness; ASTM A513 mechanical tubing with
¾" MPT nipple outlet and neoprene bushing, crimped in place, moisture seal.
A minimum 10-inch-long, 1" CTS (0.099 wall thickness) PE pigtail shall extend from the
steel pipe casing. The 1" CTS carrier pipe shall be medium density PE 2708
polyethylene, uniformly yellow in color, conforming to the latest edition of ASTM D3350
“Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”, cell
classification 234373E extruded from one of the following Performance Pipe Company
Marlex HHM TR-418Q Resin or Ineos Fortiflex® K38-20-160 Resin.
The transition from steel to PE shall occur within 6.5 inches of the threaded end. Risers
shall include insulation between the steel casing and the PE carrier pipe by means of an
o-ring/air space configuration or using a sleeve made of non-heat conducting materials.
All exposed threads and openings shall be covered with protective caps. The riser label
shall include manufacturers name, part number, lot number and casing pipe shall have
indication of ground level.
Anodeless risers must have approved meter valves included.
b. Anodeless 2"PE IPS X 2" MPT STRAIGHT - The 2" casing pipe shall be fabricated
from ASTM A53 Schedule 40, Grade A steel pipe. The casing shall also conform to the
following requirements: gray fusion bonded epoxy coated (8 mil minimum thickness); 72
inches long, 2" MPT nipple outlet and neoprene bushing, crimped in place, moisture
seal.
A minimum 10-inch long, 2" IPS (0.216 wall thickness) PE pigtail shall extend from the
steel pipe casing. The 2” IPS carrier pipe shall be medium density PE 2708
polyethylene, uniformly yellow in color, conforming to the latest edition of ASTM D3350
“Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”, cell
classification 234373E extruded from one of the following: Performance Pipe Company
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 7
Marlex HHM TR-418Q Resin or Ineos Fortiflex® K38-20-160 Resin; SDR 11.0.
The transition from steel to PE shall occur within 6.5 inches of the threaded end. Risers
shall include insulation between the steel casing and the PE carrier pipe by means of an
o-ring/air space configuration or using a sleeve made of non-heat conducting materials.
All exposed threads and openings shall be covered with protective caps. The riser label
shall include manufacturers name, part number, lot number and casing pipe shall have
indication of ground level.
Anodeless risers must have approved meter valves included.
3. Approved Manufacturers: The City of Palo Alto approved anodeless gas riser manufacturer
is RW Lyall & Company, Inc. Any other anodeless gas riser manufacturer such as Elster
Perfection, Continental Industries, George Fischer Central Plastics Company, or equal must
receive prior approval.
E. Electrofusion Tapping Tees and Couplings: All electrofusion tapping tees and couplings
supplied under this section shall be in compliance with ASTM F1055-1998 “Standard
Specification for Electrofusion Type Polyethylene Fittings for Outside Diameter Controlled
Polyethylene Pipe and Tubing”, and be manufactured in accordance with ASTM D2513-09a
“Standard Specification for Polyethylene (PE) Gas Pressure Pipe, Tubing and Fittings”.
1. All electrofusion tapping tees shall be DAA designated: 1-1/4” x 1”, 2" x 1", 4" x 1", 6" x 1",
and 8" x 1" (IPS x CTS) and, 4" x 2", 6" x 2", and 8" x 2" (IPS x IPS) - main size x outlet size.
2. All electrofusion couplings 1-1/4” and larger (including coupling reducer 2” x 1-1/4”) shall be
IPS, 4710 HDPE; SDR 11 (2” x 1-1/4” and 2”) and SDR 11.5 (4” through 8”) ANSI/NSF 61
listed; 1” coupling shall be CTS, 4710 HDPE.
3. Markings: Electrofusion tapping tee and coupling markings shall be in compliance with the
latest edition of ASTM F2897 “Standard Specification for Tracking and Traceability Encoding
System of Natural Gas Distribution Components (Pipe, Tubing, Fittings, Valves, and
Appurtenances)” and consist of a 16-digit alpha-numeric code and scannable code-128
barcode, or QR code, with standardized encoding of pipe specifications as described in the
referenced Standard.
4. Approved Manufacturers: The City of Palo Alto approved electrofusion gas tapping tee and
coupling manufacturer is Friatec (Frialen Safety Fittings). Any other electrofusion gas tapping
tee and coupling manufacturer such as Kerotest (Innogaz Electrofusion Products) or equal
must receive prior approval.
F. Valve Boxes: Valve boxes for 2” through 8” valves shall be Oldcastle Precast/Christy G05TBox
Traffic Valve Box with G05CT non-locking type metal traffic type lid marked “GAS”. Corrugated
8” HDPE pipe shall be used as valve box extension for gas valve sizes 2” through 8" diameter.
Valve supports shall be supplied for 2" valve sizes only and be manufactured by C. P. Test
Services Inc., model FPKPV2.3, or approved equal.
G. Tracer Wire: Tracer wire shall be 10 AWG solid copper wire coated with 45 mils Type HMW - PE
insulated conductor, yellow in color. The wire shall meet all requirements of the latest editions of
ASTM D1351 and ASTM B8 and shall be UL listed as direct burial wire for temperatures between
-20o C and 80o C for circuits not exceeding 600 volts. The surface of the insulation shall be
durably marked, at intervals not exceeding 24 inches, with only the following information:
maximum working voltage "600 VOLTS", wire type, manufacturer's name or trademark, AWG
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 8
size, and UL required markings. Tracer wire shall be installed on all polyethylene mains and
services.
H. Meter Valve: Meter valves shall meet all applicable parts of CFR Title 49, Part 192 and
ASME/ANSI B16.33, and shall be insulated Mueller H-11179 (3/4", 1-1/4", or 2"), with a 3/4", 1-
1/4", or 2" steel plug. Bypass valves shall be non-insulated Mueller H-11175 (3/4”, 1-1/4”, or 2”)
with a 3/4”, 1-1/4”, or 2” steel plug. The City of Palo Alto approved meter valve manufacturer is
Mueller Company. Any other meter valve manufacturer must receive prior approval.
I. Anode Boxes: Anode box shall be Oldcastle Precast/Christy G05TBox Traffic Box with G05CT
non–locking type metal traffic lid marked "ANODE".
J. Warning Tape: Warning tape must be non-metallic, a minimum of 6” wide, “yellow” in color and
have the following print line” CAUTION: GAS LINE BURIED BELOW”. Warning tape must be
installed in all open excavations at 12” above the natural gas pipeline.
K. Excess Flow Valves (EFV): All EFVs supplied under this section shall be in compliance with the
requirements of CFR Title 49, Part 192.381 “Service lines: Excess Flow Valve Performance
Standards” and, where applicable, MSS SP-115 “Excess Flow Valves, NPS 1-1/4” and Smaller,
for Fuel Gas Service”. All EFVs shall be tested in accordance with the latest edition of ASTM
F1802 “Standard Test Method for Performance Testing of Excess Flow Valves”.
1. All EFVs must be manufactured within 6 months of the date of sale to the City.
2. The design of excess flow valves shall incorporate a bypass to allow the valve to
automatically reset and resume normal operation after repairs are made to the severed gas
line. Each valve shall be fixed or anchored to the interior of the fitting to preclude movement
of the valve.
3. The polyethylene portion of EFV shall be one piece molded medium density PE 2708
polyethylene confirming to the latest edition of ASTM D3350 “Standard Specification for
Polyethylene Plastics Pipe and Fittings Materials”, cell classification 234373E extruded from
one of the following: Performance Pipe Company Marlex HHM TR-418Q Resin or Ineos
Fortiflex® K38-20-160 Resin.
4. Each valve also shall have an affixed tag, identifying the EFV’s capacity range and flow
direction, and be individually packaged and supplied with the operating instructions. An
additional stainless-steel tag or washer shall be included in the package indicating the size
and flow capacity of the valve, which will be attached to the gas riser.
5. Markings: EFV markings shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of
a 16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with
standardized encoding of pipe specifications as described in the referenced Standard.
6. Approved Manufacturers: The City of Palo Alto approved EFV manufacturer is UMAC. Any
other EFV manufacturer such as Elster Perfection or equal must receive prior approval.
a. APPROVED MODELS (shall be designed for electrofusion applications):
UMAC
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 9
Model 41, 1” CTS Series 1800
Model 41, 1” CTS Series 2600
Model 41, 1-1/4” IPS Series 5500
Model 41, 2” IPS Series 5500
Model 41, 2” IPS Series 10000
Table 4: EFV Trip and Load Information
EFV Models
Inlet
Pressure
(PSIG)
Pressure Drop at
Typical Load
(PSIG)
Minimum
Trip Point
(SCFH)
Service Length
Protected
(FT)
Model 41, 1” CTS, Series 1800 10 0.44 1800 213
Model 41, 1” CTS, Series 2600 10 0.9 2600 205
Model 41, 1-1/4” IPS, Series 5500 10 1.3 5500 23
Model 41, 2” IPS, Series 5500 10 1.3 5500 1899
Model 41, 2” IPS, Series 10,000 10 0.51 10,000 667
b. DESIGNATION:
i. 1” Service (CTS):
Medium Capacity: Model 41, 1” CTS, Series 1800 – typical customer load between
250 SCFH and 1,600 SCFH.
High Capacity (I): Model 41, 1” CTS, Series 2600 – typical customer load between
1,400 SCFH and 2,200 SCFH.
High Capacity (II): Model 41, 1-1/4” IPS, Series 5500 – typical customer load
between 2,000 SCFH and 4,800 SCFH. This EFV requires transition from 1-1/4”
IPS to 1” CTS, as 1” CTS for this size is not available.
ii. 2” Service (IPS):
Medium Capacity: Model 41, 2” IPS, Series 5500 – typical customer load 4,800
SCFH or less
High Capacity: Model 41, 2” IPS, Series 10,000 - typical customer load between
4,400 SCFH and 8,800 SCFH
Pressure Drop: An average pressure drop across EFV at an inlet pressure of 10
psig shall not exceed: for 1” CTS - 0.6 psig @ 700 scfh, 1.1 psig @ 1800 scfh, 1.1
psig @ 2600 scfh, and 1.3 psig @ 5500 scfh.
Dimensions: 1” EFV shall be 1” CTS with 0.099” min. wall thickness with a
minimum length of 10”. 2” EFV shall be 2” IPS SDR 11 with 0.216” min. wall and a
minimum length of 10”. Valves shall be supplied with plain pipe ends.
iii. Installation: EVFs shall be installed in compliance with CFR Title 49, Part 192.383
“Excess Flow Valve Installation”. If EFV on a service line is not feasible due to
customer application (can interfere with normal operation) or is not commercially
available, in compliance with CFR Title 49, Part 192.385 “Manual Service Line Shut-
Off Valve Installation”, a manual service line shut-off valve near the source of gas
must be installed.
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CITY OF PALO ALTO Section 2685 Page 10
L. Meter Boxes: Curb meter installation in sidewalk or planting strip will be allowed only when there
is no above ground location on the property (the building occupies the entire property or
underground parking garage prohibits above ground installation). All meter boxes shall be
supplied and installed by the Contractor when box replacement is required, or a new service is
installed. Meter boxes and lid shall have H-20 load rating and shall not be installed in driving
lanes of public or private streets. Lids shall have “GAS” marked on them.
x Armorcast 24”x36”x18” Polymer Concrete Box Assembly (Part No. A6001974PCX18-1
Each/Assembly), Polymer Concrete Cover (Part No. A6001975TDZ-1 Each/Assembly), RPM
Drop-In Reading Lid Marked as “GAS” (Part No. A6000482T-H7-1 Each/Assembly), Polymer
Concrete Plug (Part No. A60000H7-PLUG-CPA – 1 Each/Assembly), and Box Extension (Part
No. A6001974PCX12-3 Each).
x Armorcast 30”x60”x36” Polymer Concrete Vault Assembly (Part No. A6001460PCX36-1
Each/Assembly), Polymer Concrete Cover (Part No. A6001456TDZ-2 Each/Assembly), RPM
Drop-In Reading Lid Marked as “GAS” (Part No. A6000482T-H7-2 Each/Assembly), Polymer
Concrete Plug (Part No. A60000H7-PLUG-CPA – 2 Each/Assembly),and Box Extension (Part
No. A6001974PCX12-1 Each).
M. Valve Extensions for Polyethylene Gas Ball Valves: Valve extensions shall be installed when
the valve’s actuator is 4’ or more below the finished grade. The extension shall be a telescopic
spindle designed to operate polyethylene gas ball valves (with 2” operating square actuator)
specified in Section 2.01 of this Specification. The extension design shall incorporate the
following features:
x The conical key adaptor that fits most standard T-keys.
x Lock spring preventing the telescopic part from collapsing during installation.
x Protection again penetration of impurities under key adaptor.
x Yellow indication plate with the inscription “1/4” turn, “Ball valve” and indication of “Open-Close”
positions.
x Key adaptor – cast stainless steel.
x Inner tube – galvanized steel.
x Outer tube – polyethylene.
x Actuator adaptor – stainless steel designed to operate 2” operating square actuator.
Approved Manufacturers: The City of Palo Alto approved valve extension manufacturer is
American AVK Co. Any other valve extension manufacturer must receive prior approval.
2.02 STEEL GAS MATERIAL
A. Steel Pipe - Gas Carrier: All steel pipe supplied under this Section shall conform to the
requirements stated in CFR Title 49, Part 192.55 “Steel Pipe” and shall conform to the latest
edition of ASTM A106/A53, Type E (Electric-resistance-welded) or S (seamless), Schedule 40,
Grade B steel pipe. The pipe shall contain markings in accordance with requirements of CFR
Title 49, Part 192.63 “Marking of Materials”, including pipe manufacturer’s name, material, size,
type, grade, pressure ratings, and date of pipe manufacture.
Markings: Pipe marking shall be in compliance with the latest edition of ASTM F2897 “Standard
Specification for Tracking and Traceability Encoding System of Natural Gas Distribution
Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of a 16-digit
alpha-numeric code and scannable code-128 barcode, or QR code, with standardized encoding
of pipe specifications as described in the referenced Standard.
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 11
B. Steel Pipe – Gas Carrier Coating: The external protective coating shall be in compliance with
CFR Title 49, Part 192.461 “External Corrosion Control: Protective Coating”, and NACE. The
pipe shall be coated by application of Fusion Bonded Epoxy (FBE). The coating resin shall be
virgin, high density polyethylene 30 mil extruded coatwrap. The resin color shall be yellow. The
coating shall contain markings including pipe manufacturer’s name, material, size, type, grade,
pressure rating, coating manufacturer’s name, date of pipe manufacture and date of coating.
Steel Pipe – Gas Carrier Rehabilitation Coating System minimum requirements:
x Must meet all applicable NACE standards.
x Must comply with requirements of CFR Title 49, Part 192.461 “External Corrosion
Control: Protective Coating”.
x Must not interfere with Cathodic Protection and prevent cathodic disbondment.
x Shall be designed by manufacturer for application directly on and being compatible with
the existing coating.
x Require minimal surface preparation.
x Shall be multilayer system including at min. primer, coating (wrap – wax tape), and, if
necessary, in the opinion of Cathodic Technician, outerwrap for above or below ground
application.
x Shall be able to conform to irregular shapes including pipe supports and fasteners (above
ground application attached to the bridges).
x Must resist weathering and UV (above ground application).
x Nontoxic, noncarcinogenic, minimum VOCs.
x Provide great adhesion and cohesive and tensile strength.
x Be able to withstand deformation of the substrate.
x Impact resistance per the latest edition of ASTM G14 “Standard Test Method for Impact
Resistance of Pipeline Coatings (Falling Weight Test).
x Dielectric strength per the latest edition of ASTM D149 “Standard Test Method for
Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating
Materials at Commercial Power Frequencies”.
x Puncture resistant.
x Fast drying/curing compounds.
x Must comply with all applicable Environmental Regulations.
x Must be installed in accordance with the system manufacturer’s recommendations.
Approved Coating System(s):
x Primer- Trenton Temcoat 3000, or approved equal.
x Coating – Trenton #1 Wax-Tape (below ground application) or approved equal. If in the
opinion of Cathodic Technician additional mechanical protection is required and
depending on the soil/backfill conditions apply either Poly-Ply, Guard-Wrap, Glas-Wrap,
or MC Outerwrap. No drying or curing time is required and after application the pipe can
be immediately backfilled.
x Coating – Trenton #2 Wax-Tape (above ground application) or approved equal. If in the
opinion of Cathodic Technician additional mechanical protection is required apply Trenton
MC Outerwrap. Trenton #2 Wax-Tape can be painted using an acrylic latex paint.
Depending on atmospheric conditions shall be allowed 2-14 days before paint
application.
C. Steel Valves: All steel valves supplied under this Section shall conform to CFR Title 49, Part
192.145 “Valves”, and meet the minimum requirements of the latest edition API 6D
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CITY OF PALO ALTO Section 2685 Page 12
“Specifications for Pipeline Valves”. The valve shall be ANSI class 150 (unless specified higher
during specific order), ball valve with weld ends full port only for 2”, 4”, 6”, 8”, 10” sizes; reduced
port for 12” size is allowed if full port is unavailable. Each valve shall be manufacture air tested
to ensure integrity and leak tightness. The valves shall be shipped with 2” operating squares (2”
through 6”) and gear operator (8” through 12”) with cast steel ultra-stop, unless specified
otherwise during the order. The valve shall have markings stating at minimum manufacturer,
size, pressure rating/class, and date of manufacture. The minimum end-to-end length for weld
end valves shall be as follows:
x 2” – 11.81” (full port)
x 4” – 12.80” (full port)
x 6” – 15.35” (full port)
x 8” - 18.00” (full port)
x 10” – 21.50” (full port)
x 12” – 23.50” (full port)
Markings: Gas Valve marking shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of a
16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with standardized
encoding of pipe specifications as described in the referenced Standard.
Approved Manufacturer: The City of Palo Alto approved steel valve manufacturer for 2” through
6” is Kerotest Weldball and for 8” through 12” is Cameron (T31). Any other steel valve
manufacturer such as Ballomax by Broen, Inc. or equal must receive prior approval.
D. Flanges: Each flange or flange accessory shall conform to CFR Title 49, Part 192.147 “Flanges
and Flange Accessories”, and must meet the minimum requirements of ASME/ANSI B16.5-03
“Pipe Flanges and Flanged Fittings” and MSS SP-44-10 “Steel Pipe Flanges”. Flange shall be
ANSI class 150, pressure rating 285 PSIG, unless specified otherwise. Material shall be carbon
steel and shall conform to the requirements of the latest edition of ASTM A105 “Standard
Specification for Carbon Steel Forgings for Piping Applications”.
Markings: Flange marking shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of a
16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with standardized
encoding of pipe specifications as described in the referenced Standard.
E. Non-Pressure Control Fittings: Fittings shall conform to CFR Title 49, Part 192.149 “Standard
Fittings”. All welded fittings shall be schedule 40 and shall comply with the latest editions of
ASTM A234 “Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel
for Moderate and High Temperature Service” (materials) and ASME B16.9 “Standards for Pipes
and Fittings” (dimensions). All threaded fittings shall be malleable iron, IPT, finish black (BLK),
conforming to the latest editions of ASTM A197 “Standard Specification for Cupola Malleable
Iron” (materials) and ASME B16.3 “Malleable Iron Threaded Fittings” (dimensions).
Markings: Fitting markings shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of a
16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with standardized
encoding of pipe specifications as described in the referenced Standard.
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CITY OF PALO ALTO Section 2685 Page 13
F. Pressure Control Fittings: Fittings top and bottom halves shall be forged steel and be in
compliance with the latest edition of ASTM A105 “Standard Specification for Carbon Steel
Forgings for Piping Applications”. All fittings shall have a class 150 flange and meet
requirements of ANSI B16.5 “Flanges and Bolt Dimensions Class 150 to 2500” and have a
maximum working pressure of 275psig.
Line Stopper Fittings “Low Pressure” (H-17190):
For steel pipelines 2” to 4” in diameter, low pressure stopper fittings (half pressure control
fittings), weld type, may be used to stop the flow of gas.
Line Stopper Fittings “Full Encirclement”:
For steel pipelines 2” to 12” in diameter, full encirclement pressure control fittings may be used to
stop the flow of gas. Line stopper, Bottom-out, or Side-out fittings may be used for pipeline
connections to control flow.
x 2” (H-17155, H-17160)
x 2-1/2” (H-17155, H-17160)
x 3” to 12” (H-17255, H-17260355, H-1735560)
Markings: Gas line stopper fittings shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of a
16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with standardized
encoding of pipe specifications as described in the referenced Standard.
Approved Manufacturer: The City of Palo Alto approved steel line stopper fitting manufacturer
is Mueller Co. – Gas Division. Any other steel line stopper fitting manufacturer must receive prior
approval.
G. Drilling Nipples (Sav-a-Valve – H-17490): Fitting shall be forged steel and be in compliance
with the latest edition of ASTM A105 “Standard Specification for Carbon Steel Forgings for Piping
Applications” and have a maximum working pressure of 250psig.
Markings: Drilling nipples shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of a
16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with standardized
encoding of pipe specifications as described in the referenced Standard.
Approved Manufacturer: The City of Palo Alto approved steel line stopper fitting manufacturer
is Mueller Co. – Gas Division. Any other steel line stopper fitting manufacturer must receive prior
approval.
H. Casing: Casings shall be steel pipe, Schedule 40, Grade A106. Polyethylene casings shall be
high density HDPE 4710 polyethylene pipe (DR 11) with cell classification of 345464C, D or E
per ASTM D3350 “Standard Specification for Polyethylene Plastics Pipe and Fittings Materials”.
I. Vent Pipe: Vent pipes for steel casings shall be 2-inch in diameter, Schedule 40, Grade A106
and shall terminate in a protected location, above ground, with back-to-back 90-degree elbows to
avoid water intrusion. Vent pipes for polyethylene casings shall be 2” in diameter, high density
HDPE 4710 polyethylene pipe (DR 11) with cell classification of 345464C, D or E per ASTM
D3350 “Standard Specification for Polyethylene Plastics Pipe and Fittings Materials” and shall
transition to steel schedule 40 pipe and terminate in a protected location above ground with
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 14
back-to-back 90-degree elbows to avoid water intrusion.
J. Casing Insulators: Commercially available casing insulators with a minimum of 4 plastic
runners, each runner a minimum of 1/4" high, shall be installed at 5 feet maximum intervals on
the steel gas main prior to insertion. Insulators shall be sized to center the gas main in the
casing.
K. Cable Protectors: When inserting the pipe into the casing, the Contractor shall use a suitable
cable protector on the casing end to protect the pipe and pipe coating from damage. Cable
protectors shall be left in place after pipe insertion is completed.
L. Casing End Seals: End seals shall be Link SealTM, or approved equal, capable of forming a
watertight seal at the ends of the casing. Seamless or wrap around end seals must be used in
addition to Link SealTM to perform a watertight seal between the casing and carrier pipe.
Seamless and wrap around end seals shall be made of synthetic rubber and secured with
stainless steel banding clamps.
M. Repair Clamp: Clamp shall be used as a temporary repair only and shall not remain in service
for extended periods of time. Components should be resistant to corrosion and gaskets must be
gridded, Nitrile (Buna-N) and resistant to natural gas. The clamp shall be rated for an operating
pressure greater than the system pressure it is being installed on.
a. ¾” through 1-1/4” diameter:
i. Smith Blair Redi-Clamp model 244, full circle band with gasket.
b. 2” through 12” diameter:
i. Mueller model 220, regular gasket coverage. Bolts should be torqued to
manufacturer specifications depending on size: 2”-4” (175psig), 6”-8” (100psig), 10”-
12” (75psig).
L.
2.03 PVC PIPE AND TUBING
This specification covers PVC pipe, tubing, and fitting for use only to maintain or repair existing PVC
gas piping. All PVC pipe, tubing, and fitting used under these specifications shall be in accordance
with the latest edition of ASTM F2817 “Standard Specification for Poly (Vinyl Chloride) (PVC) Gas
Pressure Pipe and Fittings for Maintenance or Repair.
A. Pressure Control Fittings: Fittings components shall have an alloy composition that
complies with requirements of CFR Title 49, Part 192.455(f) “External Corrosion Control:
Buried or submerged pipelines Installed after January 31, 1971”. The fitting must have a
maximum working pressure greater than the system pressure of which the fitting is to be
used on.
1. Line Stopper Fittings:
a. For PVC pipelines 2” in diameter, coated steel fittings or stainless-steel fittings may be
used if all components of the fitting are constructed of an alloy material not requiring
cathodic protection. Approved stopping system is Kleiss MCS60-2.
b. For PVC pipelines 3” to 8” in diameter, coated steel fittings or stainless-steel fittings may
be used if all components of the fitting are constructed of an alloy material not requiring
cathodic protection. Approved stopping system is Kleiss MCS60-38.
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 15
2. Markings: Line stopper fittings shall be in compliance with the latest edition of ASTM F2897
“Standard Specification for Tracking and Traceability Encoding System of Natural Gas
Distribution Components (Pipe, Tubing, Fittings, Valves, and Appurtenances)” and consist of
a 16-digit alpha-numeric code and scannable code-128 barcode, or QR code, with
standardized encoding of pipe specifications as described in the referenced Standard.
3. Approved Manufacturer: The City of Palo Alto approved PVC line stopper fitting
manufacturer is Kleiss. Any other steel line stopper fitting manufacturer must receive prior
approval.
2.04 WORK MATERIALS TO BE FURNISHED BY THE CITY
The City will provide all gas meters, regulators, and pipe nipples and fittings required to connect the
gas meter to the new riser.
2.05 WORK MATERIALS TO BE FURNISHED BY THE CONTRACTOR
Work materials supplied by the Contractor shall include but not be limited to:
A. All materials, equipment and appurtenances needed to complete installation of new PE mains
and services.
B. Expendable Concrete Materials: Materials required to install and finish Portland cement
concrete, such as form lumber, tie-wire, nails, etc.
C. Concrete: All Portland cement concrete including reinforcing steel, wire mesh, etc.
D. Temporary and Permanent Fencing: All fencing including traffic barricades required to provide a
barrier between vehicular/pedestrian movements and excavations.
E. Trench Backfill Sand: All backfill sand shall be clean imported sand, rock and salt free. Bay
sand shall not be accepted.
F. Paving Material: All materials required for temporary and permanent street repairs including
base materials.
G. Landscaping Materials: All landscaping materials, irrigation, plants and surface materials that are
damaged due to this Work.
H. Traffic Control Materials: All materials required to direct vehicular/pedestrian traffic including
striping, loop detectors, reflectors, etc. that may be damaged by the Work.
I. Drilling fluids and bentonite for direction drilling operations.
J. Non-skid trench plates.
K. Project notifications signs.
2.06 MANUFACTURER'S TESTING
A. Minimum burst pressure tests, conducted in accordance with the latest editions of ASTM D1599
“Standard Test Method for Resistance to Short-Time Hydraulic Pressure of Plastic Pipe, Tubing
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 16
and Fittings” and ASTM D2290 “Standard Test Method for Apparent Hoop Tensile Strength of
Plastic or Reinforced Plastic Pipe”, and as incorporated in ASTM D2513-09a “Standard
Specification for Polyethylene (PE) Gas Pressure Pipe, Tubing and Fittings”, shall be performed
by the manufacturer to determine the short term rupture strength of the pipe and fittings
furnished. The minimum short term burst pressure shall be that required to develop a minimum
tensile strength value at yield of 2520 psi. This test shall be performed on each lot of pipe
ordered, and the manufacturer shall provide all test data as requested by the City. A lot shall
mean all material covered by a single item on a City order. Fittings shall be tested at the
frequency specified in the latest edition of ASTM D2513 “Standard Specification for Polyethylene
(PE) Gas Pressure Pipe, Tubing and Fittings”, Annex A1.
B. Sustained pressure tests shall be performed to ensure that the pipe and fittings supplied have
passed the sustained pressure test outlined in the latest edition of ASTM D1598 “Standard Test
Method for Time-to-Failure of Plastic Pipe Under Constant Internal Pressure”. The minimum
sustained pressure shall be that required to produce a minimum hoop stress value of 1320 psi.
Testing frequency shall meet or exceed that called for in ASTM D2513-09a “Standard
Specification for Polyethylene (PE) Gas Pressure Pipe, Tubing and Fittings”, Annex A1.
Manufacturer shall provide test data for each lot of pipe and/or fittings ordered as requested by
the City.
C. Polyethylene Fusion Joints (Butt and Electrofusion): All joint integrity qualification tests shall
be performed by the manufacturer in accordance with the requirements of CFR Title 49, Part
192.281 (c) (1) and (3) “Plastic Pipe” and Part 192.283 (a) (1) (i) and (iii) “Qualifying Joining
Procedures”.
D. Mechanical Plastic Joints: All joint integrity qualification tests shall be performed by the
manufacturer in accordance with the requirements of CFR Title 49, Part 192.281 (e) “Plastic
Pipe” and 192.283 (b) “Qualifying Joining Procedures”.
E. Solvent Cement (PVC Repair Only): All joint integrity qualification tests shall be performed by
the manufacturer in accordance with the requirements of CFR Title 49, Part 192.281 (b) “Plastic
Pipe” and 192.283 (a) “Qualifying Joining Procedures”.
2.07 SUBMITTALS AND QUALITY CONTROL
A. The manufacturer shall submit to the City a written quality control procedure conforming to the
latest edition of ASTM D2513 “Standard Specification for Polyethylene (PE) Gas Pressure Pipe,
Tubing and Fittings”, Annex A1, or as required by CFR Title 49, Part 192.283 “Plastic Pipe” and
192.283 “Qualifying Joining Procedures”, which shall be subject to approval by the City.
B. The manufacturer shall permit City representatives to tour extrusion facilities for the purpose of
evaluating manufacturer's capabilities. The tour shall be done during extrusion of a City order, or
if prior to order placement during the extrusion of a similar material.
C. The manufacturer shall certify that the plastic pipe and or fittings supplied to meet all the
requirements of this Specification. When requested by the City, the Manufacturer shall supply
certification for all items ordered; failure to do so shall be cause for order rejection.
2.08 INSPECTION
The City reserves the right to inspect each order upon delivery and, at the option of the City, reject
any items not meeting this Specification.
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CITY OF PALO ALTO Section 2685 Page 17
PART 3 – EXECUTION
3.01 POLYETHYLENE PIPE INSTALLATION – GAS MAINS
A. Minimum Cover: Gas mains shall be installed with a minimum cover of 30", as measured
vertically from the top of pipe to the top of pavement.
B. Underground Clearance: Unless otherwise specified, a minimum of 12 inches vertically and 48
inches horizontally, unless a reduced separation is approved by Engineering, shall be maintained
between the pipe surface and other utility lines or adjacent foreign structures. If it is not possible
to maintain required vertical clearance from other structures, the Contractor shall receive prior
approval or case the gas main in steel pipe or concrete at the discretion of the City's
representative.
C. Gas Pipe Bedding: Trench shall be free of debris, sharp rocks, etc. before adding the sand bed
for the new gas main. Sandbed shall have a minimum thickness of 4" below and 12” above the
gas main.
D. Tracer Wire Connections: One tracer wire shall be installed with each section of Polyethylene
pipe. All tracer wire connections shall be made with the Nicotap T-102-D lateral splice sleeve
wrapped with 3M Scotch-Seal Mastic Tape Compound 2229 and electrical tape. All Nicotap
fittings must be installed with tooling specified by the manufacturer; the use of pliers or other
crimping devices will not be allowed. Tracer wires from the four pipelines feeding into an
intersection will be terminated at an anode box located by the “northerly” valve. Tracer wire shall
have knots tied in the wire as follows: north wire - no knot attached to terminal 1 of the anode
box; east wire - one knot attached to terminal 2; south wire - two knots attached to terminal 3;
west wire - three knots attached to terminal 4. Each wire shall extend a minimum five feet above
grade. The Drawings detail installation requirements. Tracer wires from steel gas mains inserted
into casings shall be extended to the closest “westerly” anode box with four knots tied.
E. Valves: Valves shall be installed at the marked locations. Valve supports are required for 2"
valves only. Valves shall be installed with the operating nut on top, facing vertically up. The City
will not accept valves that are cocked or oriented in any direction except up.
F. Anode Boxes: Anode boxes shall be installed at locations shown on plans or as directed by the
City Inspector. Anode boxes shall be installed in the same manner as valve boxes.
G. Pressure Test: The Contractor will conduct air pressure tests at 100 psig on the newly installed
system, including all main and service lines, for a minimum time of 25 hours. The City will provide
a pressure chart recorder to document all air tests. The pressure shall not decrease during the
test period. A digital gauge shall be supplied by the Contractor at a separate location to record
pressure at the start and end of pressure test. Tests shall be performed on each block of main
installed after service installation is completed.
H. Boring: All underground utilities shall be located and potholed prior to the start of boring. One
tracer wire shall be attached to all pipe prior to insertion into the bore hole. All pipe ends shall be
sealed with a butt fusion end cap or similar fitting prior to pulling into a bore hole.
I. Sealing Installed Piping: Contractor shall seal open piping with butt fusion end caps at the end
of each workday. No open pipe ends will be allowed.
3.02 GAS SERVICE (INSERTION INTO EXISTING PIPE)
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CITY OF PALO ALTO Section 2685 Page 18
When inserting a PE pipe into an existing (abandoned) pipe, the Contractor shall follow the
procedures listed below to minimize gas service disruption:
A. Ensure ends of steel casing are free from debris that may damage the PE pipe.
B. Install new 1” PE service by pushing the new PE pipe through casing by hand.
C. Install new riser and connect new 1”PE service to main.
D. Pressure test the entire length of inserted pipe, fittings, and appurtenances for a minimum period
of 24 hours at a minimum pressure of 100 psig with air.
E. Perform all required house plumbing modifications.
Inserting new PE pipe into an existing (abandoned) pipe is not a typical installation method performed
on the City of Palo Alto natural gas distribution system and approval must be granted prior to
insertion.
3.03 GAS HOUSE LINES
All materials and installation methods must comply with the latest City adopted version of Uniform
Plumbing Code.
3.04 INSTALLATION – GAS SERVICES
A. Tapping Tee Installation
1. Contractor shall install tapping tees at the locations marked by the City. Bell holes shall be
excavated, if installing the gas mains by boring methods, at each tapping tee installation site
to provide an adequate work area for installation and inspection of tapping tees. The tapping
tees shall be installed in accordance with Section 2500 by the person(s) qualified by the City
to install tapping tees. Tapping tee fusions must be conducted in the presence of, or with the
prior approval of, the City Inspector. TAPPING TEES SHALL ONLY BE INSTALLED ON
THE TOP OF THE GAS MAIN.
2. The main shall be tapped after the tapping tee outlet coupling has cooled for the time period
specified in Section 2500 and the service line has been soaped and pressure tested. The
manufacturer supplied tapping wrench or fitting shall be the only tool used for turning the
tapping tee cutter to avoid tapping the backside of the main or loss of the cutter into the
main. Allen wrenches shall not be used.
3. Tapping tee cutter shall be moved back to the top of the tee tower prior to seal cap
installation.
B. Service Pipe Installation with Excess Flow Valves
1. All services must be installed with boring type devices, approved by the Engineer, except in
cases where ground conditions or existing underground utility congestion precludes it. Open
cut trenching of services must be approved by the Engineer.
2. Excess flow valves shall be installed on all service lines, where commercially available, as
close as practical to the tapping tee, connected by electrofusion couplings. Care shall be
taken to ensure that the excess flow valve is installed with the arrow pointing towards the
riser (away from the tapping tee).
3. For 1” services, a 1" cap shall be attached in accordance with Section 2500 by a qualified
person(s) and in the presence of, or with the prior approval of, the City's Inspector, to the end
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 19
of the 1" service pipe, and tracer wire attached to the service pipe prior to inserting the pipe
into the bore hole. Services shall be one continuous polyethylene pipe with no fusion joints.
4. For 2” services, a 2” cap shall be attached in accordance with Section 2500 by a qualified
person(s) and in the presence of, or with the prior approval of, the City’s Inspector, to the end
of the 2” service pipe, and tracer wire attached to the service pipe prior to inserting the pipe
into the bore hole. Services shall be one continuous polyethylene pipe with no fusion joints.
Contractor shall also install 2” inline ball valve as close to the outlet of the tapping tee as
possible.
5. A qualified person shall make all connections between the excess flow valve and the service
line by electrofusion couplings in accordance with Section 2500 and in the presence of, or
with the prior approval of, the City's Inspector.
6. A qualified person shall connect by electrofusion the service line to the service riser in
accordance Section 2500 and in the presence of, or with the prior approval of, the City's
Inspector.
7. The Contractor shall install a meter valve, by-pass assembly (if indicated on construction
drawings), and end plug on each service riser. Stop cock shall be installed with operating
shut off nut facing away from structure (or facing the opening of the curb meter vault lid) with
the regulator at its left side per City Standard Specification and Details.
8. The location of all gas services shall be marked by a delta symbol, 2” in height, impressed or
chiseled to a depth of ¼” into the curb (or sidewalk if no curb line). The base of the delta
shall be parallel to the street (or curb) and its vertex shall be located on the gas service line,
pointed toward the structure in the direction of the gas meter. The marking must be placed at
the time of service installation by attaching a line locator device to the tracer wire to ensure
that the marking is located directly above the service. All old gas markings shall be removed
prior to installation of new gas meter.
9. House line: When required, Contractor must apply for plumbing permits and coordinate
approval of houseline pressure test with Building. All materials and installation methods
must comply with the latest City adopted version of the Uniform Plumbing Code.
C. Minimum Cover: Gas services shall be installed with 24" minimum cover, as measured vertically
from top of pipe to top of pavement or below existing grade.
D. Maximum Cover: Gas services shall not be installed any deeper than 42" below existing grade
unless directed by the Engineer.
E. Service Leak Testing: Prior to tapping the main, the contractor shall conduct air pressure tests,
in the presence of qualified City staff, at 100 psig on all service lines for a minimum of 15 minutes
using a digital gauge. The pressure shall not decrease during the test period. Air pressure shall
be held until after soap testing is complete. Soap test the service connection by brushing a liquid
soap and water solution around the tapping tee base at the main, both ends of the outlet
coupling, the outlet connection of the excess flow valve, the pipe to riser connection in the
customer’s yard, and at the meter valve inlet and outlet. If any leaks appear, the City’s Inspector
will direct repair procedures.
F. Surface Restoration: Once the City’s Inspector has noted the location of the service pipe in the
customer’s property, the Contractor shall restore the customer’s surface improvements to the
preconstruction condition.
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 20
3.05 STEEL PIPE INSTALLATION
A. Welding: All steel gas carrier pipe shall be welded in accordance with CFR Title 49, Part 192,
Subpart E “Welding of Steel in Pipelines”, by a welder qualified under Section 192.227
“Qualification of Welders and Welder Operators”, and certified by the City.
B. Wrapping of Welds: Primer (Royston Roybond 747, or approved equal) and a 30-mil minimum
thickness wrapping tape shall be applied over welded joints and any other bare metal surface of
the pipe. Complete wrap shall be two (2) thicknesses of cold wrap tape covering the metal in all
places (50% overlap of the cold wrap tape) and overlapping the plant coat wrap by a minimum of
2”. Manufacturer’s primer shall not be applied to polyethylene pipe.
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 21
3.06 SYSTEM PRESSURE TEST
The Contractor will conduct an air pressure test at 100 psig on all newly installed pipelines, including
services and mains, for a minimum time of 25 hours. Test shall only be performed Monday-Thursday.
The City will provide a pressure chart recorder to document the system air test. A digital gauge shall
be supplied by the Contractor at a separate location to record pressure at the start and end of
pressure test. The pressure shall not decrease during the test period.
For pressure testing newly installed service pipelines on ABS or PVC gas mains, a separate pressure
test for a minimum of 15 minutes at a minimum of 50psig shall be performed for the service
connection tee only. All other PE service piping shall be pressure tested at a minimum of 15 minutes
at a minimum of 100psig.
All customer piping shall be inspected and approved by the building department inspector before gas
service will be instituted. Gas meters will be installed within ten working days after the building
inspector approved the building gas piping and releases a set tag for the gas meters to the Utilities
Department.
3.07 OPERATOR QUALIFICATION REQUIREMENTS
A. General Conditions: The Contractor shall have qualified persons to perform covered tasks on
the project, including polyethylene pipe joining as per Section 2500 of these standards and CFR
Title 49, Part 192, Subpart F “Joining of Materials Other Than by Welding”.
B. Qualification Testing: The Contractor shall secure a software license with Industrial Training
Services (ITS) to test and maintain Operator Qualifications (OQ) for each employee assigned to
perform covered tasks on City of Palo Alto gas projects. The Contractor shall provide the City
OQ Administrator access to Contractor’s system, for retrieval of documentation on qualified
Contractor employees.
Operator testing and qualification is required for all Contractor employees performing covered
tasks on City of Palo Alto natural gas pipelines. Individual employee will be deemed the qualified
person and shall only perform the individual task they are qualified for. The City does not
recognize span of control for Contractor personnel. The Contractor will perform the qualification
testing using their own equipment and materials, equipment for qualifying shall be the same
equipment used on the project, and all testing shall be done at the Contractors expense. At the
discretion of the City, the Contractor may be required to obtain qualification through the City or
with a City approved ITS third-party evaluator. Contractor will be required to successfully
complete the training and written exam for each task and exam may be proctored by Contractor’s
approved ITS evaluator. Contractor must perform the hands-on exam with the City or with a City
approved ITS third-party evaluator. Contractor will be responsible for all labor, material, and
travel cost required to build props or stations and test, regardless of where the testing is located
(Contractors facility or offsite).
At a minimum, all fusion equipment used must be inspected by the City and receive a
certification sticker. The certified equipment must be used to obtain Operator Qualification fusion
certification and be used to perform fusions on the project. All testing and certifications must be
coordinated with the WGW Project Manager a minimum of three weeks in advance.
Below are the minimum required Operator Qualification tasks assigned to all contractors
performing work on City of Palo Alto natural gas pipelines:
x F01.1.0721 – Joining of Pipe: Threaded Joints
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 22
x F01.1.0761 – Butt Heat Fusion (Hydraulic)
x F01.4.0781 – Electrofusion
x G01.0981 – Backfilling
x G01.1321 – Damage Prevention During Excavation Activities
x G02.0641 – Visually Inspect Pipe and Components Prior to Installation
x G02.0901 – Installation of Plastic Pipe in a Ditch
x G02.0941 – Install Tracer Wire
x G04.0911 – Installation of Plastic Pipe in a Bore
x I07.00541 – Installation and Maintenance of Mechanical Electrical Connectionsof
Exothermic Electrical Connections
x L01.a.1101 – Tapping a Pipeline with a Built in Cutter
x M08.0201 – Visual Inspection of Installed Pipe and Components for Mechanical Damage
x M08.0211 – Measure and Characterize Mechanical Damage on Installed Pipe and
Components
Polyethylene fusion requirements are addressed in full detail in Section 2300 and Section 2500
of these Specifications.
The City reserves the right to add additional qualification testing based on the work being
performed. It is the responsibility of the Contractor to request what, if any, additional qualification
testing may be required.
3.08 ABANDONMENT OF NATURAL GAS FACILITIES
A. MAINS
The City’s Water-Gas-Wastewater Operations shall perform the abandonment of the natural gas
mains after the new gas main and service pipelines meet pressure tests outlined in 3.01 and 3.06
of Section 2685. The Contractor shall notify the Engineer five (5) days in advance of the pressure
test to schedule the abandonment of the natural gas main and services.
B. SERVICES AND SERVICE RISERS
Where a new gas service is to be installed or a service reconnection is to be performed, the
City’s Water-Gas-Wastewater Operations shall cut and cap the old service near the gas main or
the reconnection point after the new gas service meets the pressure tests outlined in 3.01 and
3.06 of Section 2685.
On gas services abandoned by Water-Gas-Wastewater Operations, the Contractor shall verify
the presence of gas by opening the meter valve to ensure the service is inactive and there is no
potential hazard for combustion. After verification, the Contractor shall proceed to cut the riser
flush to grade and restore the disturbed surface to match existing.
C. VALVES
The Contractor shall perform the abandonment of valves on distribution pipelines that are
inactive and disconnected from the distribution system. The Contractor shall remove the valve
box lid and cover and restore the surface to match existing.
3.09 DESIGN STANDARDS
Polyethylene piping (medium density PE 2708) is currently the only material installed in the City’s
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 23
natural gas distribution system (except at the locations where repair work is done on steel and/or
PVC segments of the natural gas distribution system).
A. LOCATION
1. Gas mains shall be located two (2) feet off the lip of gutter on the north and east side of
streets, unless otherwise specified on the Project Drawings. Gas mains shall be twenty-four
(24) inches minimum from any parallel utility line, or as determined by the City. Gas mains
and services shall have a minimum of one (1) foot vertical clearance from any crossing utility
lines or other underground facilities.
2. Gas services shall be installed perpendicular from the gas main in the shortest straight line to
the gas meter location.
3. Above ground gas meters shall be installed on private property adjacent to the building. Curb
meter installations shall only be allowed with prior approval of the Engineer. The meter
location and installation shall be as specified on the project documents.
4. No meter or regulator shall be installed inside of a building, garage, carport, crawlspace, or in
any other enclosed area with walls on more than two sides or under a roof structure. The
Owner is responsible for installing a concrete meter pad, concrete walkway for meter access,
and bollards as required by the City.
B. DEPTH OF PIPE: Minimum depths are to be provided to the finished street surfaces, unless
otherwise specified on the Drawings.
1. The depth of new gas mains shall be installed with a minimum cover of 30”, as measured
vertically from the top of pipe to the top of pavement.
2. The depth of new gas services shall be installed with a minimum cover of 24”, as measured
vertically from the top of pipe to the top of pavement.
3. If it is not possible to maintain the above minimum cover depth requirements for new gas
mains or services, City Engineering must approve additional protection devices to be
installed that adequately prevent damage to the pipe by external forces (steel plate, casing
or concrete cap).
C. MINIMUM SIZE OF NEW MAINS AND SERVICES: The minimum new gas main size is 2”
(minimum wall thickness = 0.216”, SDR 11.0). The minimum service size for new construction is
1” (minimum wall thickness = 0.099”)
D. VALVES: Four valves shall be installed at each intersection and three valves shall be installed at
each tee (at the property line extensions as shown on Figure 3), or as shown on the construction
drawings or as directed/approved by the Engineer.
Figure 3
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 24
Install 3 valves at each gas main tee
Install 4 valves at each gas main intersection
A 2” inline ball valve will be required on all gas services 2” and larger (as shown on Figure 4).
Placement of valve shall be as close to the tapping tee as practical.
Figure 4
E. LOAD: The maximum connected load shall be used for design purposes (the total shown on the
submitted load sheet plus any anticipated future load when available). Coincidence or diversity
factors shall not be used when designing gas services.
F. CALCULATING SERVICE SIZE: The sizing of gas services shall be based on the High-Pressure
Mueller Equation (applicable for 1 psi and greater) where the length of the service is doubled to
account for fittings and a factor of safety.
Note: the absolute pressure (psia) must be used when performing calculations with the Modified
High-Pressure Mueller Equation. The standard barometric pressure correction is 14.7 psia.
G. AVAILABLE PRESSURE
The typical pressure in the City’s natural gas distribution system is approximately 20 psig. The
City’s standard delivery pressure is 7" w.c. (water column). Non-standard delivery pressures
above 7" w.c. will be limited to 14” w.c., and 1, 2, 3 and 5 psig. Approval from the Engineering
Manager is required for any delivery pressures greater than 7" w.c. For sizing:
1. Residential gas services: The pressure at the main is assumed to be 10 psig, and the
pressure at the meter set riser shall be assumed to be 8 psig, or as noted on the individual
Gas Meter Set Standard Drawings. The services shall be sized based on the calculated head
loss between the main and the riser. If the head loss is too great, then the service size shall
be increased.
2. Commercial/Industrial Services: The minimum required pressure upstream of the regulator,
and pressure loss through the riser, meter valve, and filter (if applicable), or as specified in
the notes on the individual Gas Meter Set Standard Drawings, shall be considered in the
design of the service. After calculating the minimum pressure required at the meter set riser,
the service shall be sized by calculating the head loss and comparing the calculated
pressure at the main to the available pressure as projected by the Gas Model. If the head
loss is too great, then the service size shall be increased.
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 25
PART 4 - NATURAL GAS HOUSE PLUMBING
Part 4 is only for City gas main replacement projects (CIP work) where the gas meter needs to be relocated
as part of the CIP. Any other gas house plumbing (any piping downstream of the gas meter) is the sole
responsibility of the property owner.
4.01 DESCRIPTION
The work to be performed shall consist of furnishing all tools, equipment, materials, supplies,
manufactured articles, transportation and services (including fuel, power, and essential
communication), labor, and other operations necessary for the modification of existing natural gas
house plumbing to accommodate relocation of gas meters including: obtaining required permits,
installation of new house gas pipes, new shut off valves and flexes, subsequent pressure testing of
the entire house gas plumbing system, and passing required inspections for houses located in Palo
Alto, for the City of Palo Alto. The work shall be complete and performed in strict accordance with the
Contract Specifications, and in compliance with all applicable codes and standards. All work,
materials and services not expressly shown or called for in the Contract Documents, which may be
necessary for the complete and proper construction of the Work, shall be performed, furnished, and
installed by the Contractor at no increase in cost to the City.
4.02 QUALIFICATIONS OF WORKMEN
Journeyman plumbers shall be licensed plumbers completely familiar with the design and application
of the work described.
4.03 MANUFACTURER'S RECOMMENDATIONS.
All equipment, materials, devices, etc., shall be installed in a manner meeting the manufacturer's
recommendations for the particular item. Prior to the start of work, the Contractor shall obtain and
deliver copies to the Engineer of all installation manuals, brochures and procedures that the
manufacturer issues for the items supplied. The Contractor shall be held responsible for all
installation’s contrary to the manufacturer's recommendations, unless otherwise approved by the
Engineer. If any item or piece of equipment or material is found to be installed not in accordance with
the manufacturer's recommendations, or as otherwise directed by the Engineer, the Contractor shall
make all necessary changes and revisions to achieve such compliance, at the Contractor's expense.
4.04 EXISTING GAS PLUMBING
The modification of the existing gas plumbing shall be performed by the contractor only after
receiving written approval from the Engineer. With the Engineer's authorization, the Contractor shall
perform all repairs and modifications required for code compliance of existing customer owned
natural gas plumbing. The Contractor shall remove and dispose of all abandoned gas plumbing
materials. The Contractor shall not modify the existing gas plumbing until the City’s Inspector verifies
the new stub out location.
4.05 TESTING OF CUSTOMER OWNED GAS PIPING
When required, Contractor must apply and pay for all plumbing permits, testing and retesting required
showing compliance with the Contract Documents, Codes, Regulations, and all other applicable laws.
Meter sets will not be installed until all testing has been completed and the Building Department
Inspector approves the houseline work.
A. SYSTEM PRESSURE TEST: The Contractor will conduct an air pressure test in accordance with
NATURAL GAS DISTRIBUTION SYSTEM SECTION 2685
CITY OF PALO ALTO Section 2685 Page 26
the latest adopted version of the Uniform Plumbing Code and as required by the City’s Building
Department Inspector. The pressure shall not decrease during the test. Other inspections and
tests required by the City Building Inspector, codes, ordinances, or other legally constituted
authority, shall be the responsibility of and paid for by the Contractor. Testing of the existing gas
house plumbing shall be performed prior to connecting the new supply line.
B. TESTING: Testing will be in accordance with the City’s Building Department requirements.
C. CONTRACTOR'S CONVENIENCE TESTING: Costs associated with inspection and testing
performed exclusively for the Contractor's convenience shall be the sole responsibility of the
Contractor.
D. SCHEDULE FOR TESTING
1. Testing shall be scheduled with the Building Department in advance.
2. At least 48 hours’ notice shall be provided to the Engineer when testing is required.
3. Testing that involves City personnel shall not be scheduled on Fridays.
4.06 COOPERATION WITH THE BUILDING DEPARTMENT
City building inspectors shall have access to the Work at all times and in all locations where the Work
is in progress. Contractor shall provide such access to enable the Building Department to perform its
functions properly.
A. Revising schedule: When changes of construction schedule are necessary during construction,
Contractor shall coordinate all such changes with the Building Department.
B. Adherence to Schedule: When the Building Department is ready to inspect but is prevented
due to incompleteness of the Work, all extra charges for testing attributable to the delay will be
back charged to the Contractor and shall not be borne by the City.
4.07 COORDINATION WITH CUSTOMERS
The Contractor is responsible for coordinating access to private property with the homeowners. The
Contractor shall notify the property owner/ resident at least 7 days and again 24 hours in advance of
performing work. Prior to starting work at a specific location, the Contractor shall schedule the work
with the homeowner or resident, as the customer’s presence during the work is required.
City Operations staff shall relight all pilot lights the same day (before 5:00 P.M.) after the City installs
the new gas meter and regulator. No residence shall be left out of service overnight. Each residence
shall be reconnected, and all pilot lights relit before 5:00 P.M. each day.
4.08 RESTORATION
The contractor shall restore all existing improvements and landscaping at each location to the pre-
construction condition as soon as practical, after completing the work at each house location, but in
no case later than one (1) week after Work is complete. The Contractor shall include restoration in
the appropriate bid items; no separate payment will be made for restoration.
END OF SECTION
WASTEWATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2730
CITY OF PALO ALTO Section 2730 PAGE 1
SECTION 2730
WASTEWATER DESIGN AND CONSTRUCTION STANDARDS
1.01 WASTEWATER FLOW DESIGN
A. General: A capacity study report prepared by a licensed Engineer shall be submitted to the City
of Palo Alto Utilities Engineering Department by the project’s Engineer when design (or permit)
plans are submitted for review. The report shall provide the following information for the study
area:
1. For new development connections, flow monitoring data and hydraulic analysis of the
sewage drainage basin shall be submitted to assess the new connection’s impacts on the
hydraulic characteristics of the downstream pipes within the drainage basin.
2. Pipe information for each new sanitary sewer segment, including pipe diameter, slope, invert
elevations, length, roughness coefficient for Manning’s equation, design capacity, full pipe
capacity, design flow, percentage of full pipe capacity utilized (calculated by dividing the
design flow by the full pipe capacity and multiplying by 100), and pump station operation
parameters (if applicable).
3. Land use information for conditions prior to commencement of project, immediately after
completion of project, and at build-out, including category of land use, number and type of
residential dwelling units, square footage for commercial/industrial users, square footage for
industries with unusually high water requirements, number of students (for schools), and
sewer acreage.
4. Map showing location of new sewer segments (and pump stations, if applicable), proposed
connection point(s) to existing City sewers, and location of residential/commercial/industrial
users.
B. Design: Sewer segments shall be designed for a design flow 20 years from the current year. The
Design Flow (DF) for a sewer segment is composed of three components: Peak Base
Wastewater Flow (PBWF), Groundwater Infiltration (GWI), and Rainfall-Dependent Inflow (RDI).
The Design Flow shall be based on the greater of the following two formulas:
DF = (PBWF x 0.75) + GWI + RDI
DF = PBWF + GWI
Exception: If the wastewater flow is pumped, design flows downstream of the pump station shall
be based on the maximum capacity of the pump(s).
1. Peak Base Wastewater Flow (PBWF): Average base wastewater flow (ABWF) is the
average daily dry weather flow contributed from residential, commercial, and industrial users.
ABWF is calculated using unit flow rates in Table 1-1. If supporting data indicates the need,
a higher unit flow rate should be applied for commercial/industrial users. The calculated
ABWF values must be multiplied by a Peaking Factor to account for the variations that occur
hour-to-hour and day-to-day.
PBWF = ABWF x Peaking Factor
Peaking Factor = 3.15 x ABWF -0.104
where ABWF is in million gallons per day (mgd). The Peaking Factor has a maximum of 4.0
and a minimum of 1.0.
WASTEWATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2730
CITY OF PALO ALTO Section 2730 PAGE 2
2. Groundwater Infiltration (GWI): Groundwater infiltration is groundwater that enters the
collection system from defects in the pipes, pipe joints, and sewer structures. The amount of
GWI entering the collection system depends on the structural condition of the system, the
depth of the pipes, and the elevation of the groundwater table relative to the elevation of the
sewer pipes. GWI tends to decrease during the dry-weather seasons and gradually
increases as the wet-weather season progresses. GWI is calculated by applying the GWI
unit flow rate that corresponds to the tributary area. GWI unit flow rate is shown in Table 1-1.
3. Rainfall-Dependent Inflow (RDI): Rainfall-Dependent Inflow is storm water that enters the
collection system in direct response to the intensity and duration of individual rainfall events.
In addition to being dependent on rainfall events, RDI is sensitive to soil moisture, increasing
throughout the wet-weather season as the soil moisture increases. A 20-year storm event
shall be used to determine estimated RDI for new sewers. RDI is calculated by applying the
RDI unit flow rate that corresponds to the tributary area. RDI unit flow rate is shown in Table
1-1.
Table 1-1 Unit Flow Rates for ABWF, GWI, and RDI*
Average Base Wastewater Flow (ABWF)
Unit Flow Rate
Land Use Category Land Use Designation** Unit (gpd/unit)
Residential
Single Family SF Dwelling Unit 220
Multi-Family MF Dwelling Unit 160
Transit-Oriented CC Dwelling Unit 160
Commercial CS, CN, CH Building Sq. Ft. 0.15
Research/Office Park RO Building Sq. Ft. 0.10
Light Industrial LI Building Sq. Ft. 0.10
Major Institutional MISP Building Sq. Ft. 0.15
School S Student 15
Groundwater Infiltration (GWI) = 500 gpd/acre
Rainfall-Dependent Inflow (RDI) = 1,900 gpd/acre
* All rates are based on the 2004 Wastewater Collection System Master Plan.
** Land Use Designations based on Palo Alto’s Planning Land Use Designations.
1.02 PIPE CAPACITY
The theoretical capacity of new pipes shall be calculated using Manning’s equation. The "n" value
(Manning's roughness coefficient) shall be equal to 0.009 for all HDPE sewer pipes.
Manning’s Equation:
Q (cfs) = (1.49 / n) x A x Rh2/3 x S½
Q = Flow (cfs)
n = Manning's roughness coefficient
A = Flow Area (ft2)
Rh = Hydraulic Radius (ft)
S = Slope (ft/ft)
WASTEWATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2730
CITY OF PALO ALTO Section 2730 PAGE 3
1.03 PIPE SIZE, SLOPE, DEPTH, AND ALIGNMENT
A. Pipe Size: Pipes less than or equal to 10 inches in diameter shall be sized to handle peak flows
at 75% of full pipe capacity. Pipes greater than 10 inches in diameter shall be sized to handle
peak flows at 90% of full pipe capacity. The diameter for gravity sewer mains shall be 8-inches
or larger while sewer laterals shall be 4-inches but no larger than 6-inches. A sewer lateral larger
than 6-inches serving a private property shall be considered a private main, even if it crosses the
City’s right-of-way. When a smaller sewer pipe joins a large one, the top of both pipes (crowns)
should be at the same elevation.
B. Slope: All sewers shall be designed and constructed to give a mean velocity, when flowing full,
of not less than 2 feet per second. The following are the minimum slopes that should be
provided for each sanitary sewer segment:
Sewer Size Minimum Slope (Feet per 100 Feet)
4 inch (laterals) 2.00
6 inch (laterals) 1.00
8 inch 0.34
10 inch 0.25
12 inch 0.19
15 inch 0.14
18 inch 0.11
21 inch 0.09
24 inch 0.08
27 inch 0.07
30 inch 0.06
36 inch 0.04
42 inch 0.04
Where velocities greater than fifteen (15) feet per second are attained, special provisions shall be
made to protect against displacement by erosion, shock, and hydraulic jumps at changes in
velocity.
Sewers on 20 percent slopes or greater shall be anchored securely with concrete anchors,
spaced as follows:
1. Not over 36 feet on center for grades of 20 to 35 percent;
2. Not over 24 feet on center for grades of 35 to 50 percent;
3. Not over 16 feet on center for grades of 50 percent and over.
C. Depth: In general, sewers should be placed below pressure utilities and be sufficiently deep to
receive sewage from basement. Crown (top inside surface of the pipe) of any inlet pipe shall
not be lower than the elevation of the outlet main crown in the manhole, unless otherwise
approved by the Engineer.
D. Alignment: The horizontal and vertical alignment of sewers shall be maintained by the use of
laser survey equipment. Unless otherwise approved by the Engineer, all sewers shall be
constructed straight and at uniform grade between manholes.
1.04 WASTEWATER FLOW CONTROL/BY-PASS
WASTEWATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2730
CITY OF PALO ALTO Section 2730 PAGE 4
Contractor shall furnish, install, and operate pumps, plugs, conduits, temporary piping, and other
equipment to temporarily convey the sewage or to divert the flow of wastewater for pipe
replacement/rehabilitation around the sewer reach in which work is or to be performed.
A. Temporary bypass in open pits at manhole, cleanout, and lateral-connection locations:
Contractor shall maintain uninterrupted sewer service to all properties connected to the sewer
being replaced. Appropriate rigid pipe or flexible tubing shall be used, before the end of EACH
workday, to make temporary connections to convey sewage where permanent connections could
not be made at manhole, cleanout, and/or lateral to main locations. It is prohibited to leave
standing sewage overnight in manhole and cleanout excavations.
B. Flow By-Pass: It shall be the Contractor’s responsibility to provide a pumping system with
sufficient capacity to manage existing flows plus additional flow that may occur during a rain
event. The pumping system shall have automated controls. Bypassed lines larger than 18”
diameter shall automatically switch operation to the standby pumps in the event of a primary
pump failure. The Contractor shall provide personnel to observe, fuel, and maintain the bypass
pumping system at all times when it is operating. An audible alarm shall be provided to signal
high level at the bypass point.
If the City must set up flow bypass or perform bypass pumping, whether because of contractor’s
failure to set up flow bypass or to install needed pumps, the City will deduct the cost of flow bypass or
pumping from contractor’s monthly progress payments.
Temporary bypass pipe used within truck-route roadways shall be installed below the street surface
and properly plated. Plugs shall be so designed that all or any portion of the wastewater can be
released. Plugs shall be provided with a tag line.
Standby pumps and standby power shall be provided with 100 percent redundancy. If pumping is
required on a 24-hour basis in a residential or commercial area, Contractor shall get a City permit,
construct, and use a temporary power service. If pumping is required on a 24-hour basis in an
industrial area, equipment shall be sound-attenuated in a manner to keep noise to a minimum. Noise
level shall conform to the requirements of the City's noise ordinance as stated in the City of Palo Alto
Municipal Code.
Bypass pumping shall be performed in such manner as will not damage public or private property or
create a nuisance or health menace. The pumped wastewater shall be in an enclosed hose or pipe
and shall be redirected into the sanitary sewer system. It shall be adequately protected from traffic.
If applicable, the bypass hose or pipe along the sidewalk shall be covered with a ramp to protect the
pedestrians from tripping and falling. Dumping or free flow of wastewater on private property, gutters,
streets, sidewalks, or into storm sewers is prohibited. The Contractor shall not block access to
driveways, streets, or other facilities with any flow control activities.
Temporary plugging will be permitted on pipes with diameters of 6-inches or smaller. See Section
1.05, Sewage Spill Contingency Plan for monitoring the manhole upstream of the plugged pipe.
The Contractor shall be liable for all damages associated with this work, including fines imposed on
the City for spilled sewage. After the work has been completed, flow shall be restored to normal.
The Contractor shall submit a sewage bypass pumping/diversion plan to the Engineer for review as part
of the submittal process prior to the issuance of Notice to Proceed. The Contractor shall notify the
Engineer 24 hours prior to commencing the bypass pumping operation. The Contractor’s plan for
sewage bypass pumping/diversion shall be satisfactory to the Engineer before the Contractor shall be
WASTEWATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2730
CITY OF PALO ALTO Section 2730 PAGE 5
allowed to commence sewage bypass pumping/diversion.
Bypass pumping shall be performed in conformance with all applicable local, state and federal laws
and permits issued by jurisdictional regulatory agencies. Permits required by such agencies (e.g.,
Valley Water, SFPUC, California Department of Fish and Game, Regional Water Quality Control
Board, US Fish and Wildlife, Army Corps of Engineers) for by-pass pumping shall be obtained by the
Contractor. It is the Contractor’s responsibility, while preparing the Bid, to evaluate what permits
need to be obtained and estimate fees and anticipate lead time necessary to procure the required
permits to complete the Work. Payment of all costs and expenses for such licenses, permits, and
fees shall be included in one or more bid items. No other compensation shall be paid to the
Contractor for these items or for delays caused by non-City agencies or conditions set forth in the
licenses or permits issued by other agencies.
1.05 SEWAGE SPILL CONTINGENCY PLAN
The Contractor shall submit for Engineer’s approval a “Sewage Spill Contingency Plan” consisting of
secondary containment, diversion, and pumping capable of handling the flow rate in the subject
sewer line. The Contractor is also required to:
A. Notify the on-site inspector before any main is plugged to facilitate construction work.
B. Determine the release point* if the main should not be unplugged before an overflow occurs.
C. Require a job laborer to observe the flow and monitor the rise in elevation of the sewage in the
manhole at the release point.
D. The contractor is to notify the project inspector when the elevation of the sewage is within 1.5’ of
the rim at the release point manhole.
*Release point is the lowest point in the sewer collection system tributary to the plugged line. The
manhole rim and invert elevations, and the peak flow information, can be obtained from the Engineer.
1.06 WASTEWATER MAIN REMOVAL OR ABANDONMENT
Contractor shall plug existing sewer mains to be abandoned at the downstream locations. The
abandoned pipeline shall be monitored for a 48-hour period to ensure that there is no flow in the
existing main or laterals. Upon verification of abandoned pipe, the sewer main shall be completed
filled with CDF conforming to Water, Gas, and Wastewater Utility Standards Section 2200,2.5,
“Controlled Density Fill”. Cost of sewer main abandonment shall be included in one or more bid
items.
1.07 MANHOLES
Manholes shall be installed at the following locations: at the end of each sanitary sewer segment, at
any changes in grade, size or alignment, at all intersections, and at distances not greater than 500
feet between manholes. Greater spacing between manholes may be permitted as approved by the
Engineer.
The minimum inside diameter of manhole barrel sections shall be 48 inches. A minimum inside
diameter of 24 inches for concrete grade rings shall be provided to allow man-entry access. The flow
channel through the manhole shall be made to conform in shape and slope to that of the sanitary
sewer mains. All pipes entering the manhole shall be provided with a water stop within 12 inches of
the edge of the concrete base.
For drop manholes, a drop pipe should be provided for a sewer main entering a manhole at an
elevation of 30 inches or more from the flow line of the manhole (refer to standard details). Where the
WASTEWATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2730
CITY OF PALO ALTO Section 2730 PAGE 6
difference in elevation between the incoming sewer and the top of the outlet pipe is less than 30
inches, the invert should be channeled to prevent solid deposition.
Drop manholes should be constructed with an outside drop connection. the entire outside drop
connection shall be encased in concrete.
1.08 AERIAL CROSSINGS
Support shall be provided for all joints in pipes utilized for aerial crossings. The supports shall be
designed to prevent overturning and settlement. Expansion joints shall be provided between above-
ground and below-ground sewers. The impact of flood waters and debris on the pipe shall be
considered in the design of aerial crossings.
1.09 SEWERS CROSSING STREAMS
Sewer systems shall be designed to minimize the number of stream crossings. Sewer main crossing
streams shall be installed in a casing at a sufficient depth below the natural bottom of the stream bed
to protect the sewer main. If jack and bore method is used, the design of steel casing shall be
approved by the City. If horizontal directional drilling method is used, the design shall be approved
by the City. In general, the cover requirements must be met by the permitting agency:
xx One (1) foot of cover is required where sewer pipe is located in bedrock;
x Three (3) feet of cover is required where sewer pipe is located in all other material types. In
major streams, more than three feet of cover may be required.
x In paved stream channels, the top of the sewer line should be placed a minimum of one (1) foot
below the bottom of the channel pavement.
Less cover will be approved only if the proposed sewer crossing will not interfere with future
improvements to the stream channel. Sewers located along streams shall be located outside of the
stream bed and sufficiently removed providing for future possible stream widening and to prevent
pollution by siltation during construction. Sewers crossing streams should be designed to cross the
stream as nearly perpendicular to the stream flow as possible and shall be consistent in grade.
A. Materials: Sewers entering or crossing streams shall be designed and submitted to the City for
approval. Sewers shall be constructed to remain watertight and free from changes in alignment
or grade. Material used to backfill the trench shall be stone, coarse aggregate, washed gravel, or
other materials which will not cause siltation.
B. Siltation and Erosion: Best Management Practice (BMP) methods that will minimize siltation
and erosion from the site shall be employed. The design engineer shall include in the Project
Specifications the methods(s) to be employed in the construction of sewers in or near streams to
provide adequate control of siltation and erosion. Project Specifications shall require that
cleanup, grading, seeding, and planting or restoration of all work areas shall begin immediately.
Exposed areas shall not remain unprotected for more than seven (7) days.
1.10 PROTECTION OF WATER SUPPLIES
A. Water Supply Interconnections: There shall be no physical connections between a public or
private potable water supply system and a sewer collection system, or appurtenance thereto
which would permit the passage of any sewage or polluted water into the potable supply. No
water pipe shall pass through or come in contact with any part of a sewer manhole.
WASTEWATER DESIGN AND CONSTRUCTION STANDARDS SECTION 2730
CITY OF PALO ALTO Section 2730 PAGE 7
B. Storm system interconnections: There shall be no physical connections between a public or
private development storm drainage system, or appurtenance thereto which would permit the
passage of any sewage or polluted water into the storm drain system. No storm drain pipe shall
pass through or come in contact with any part of a sewer manhole.
C. Relations to Water Works Structures: Sewers shall meet the requirements of the State Water
Resources Control Board "Criteria for the Separation of Water Mains and Sanitary Sewers".
END OF SECTION
VITRIFIED CLAY SEWER PIPE SECTION 2731
CITY OF PALO ALTO Section 2731 PAGE 1
SECTION 2731
VITRIFIED CLAY SEWER PIPE
1.01 DESCRIPTION
This section covers the installation of new vitrified clay sewer pipe (VCP) for spot repairs to correct
condition defects such as broken pipe, pipe with sever cracks, protruding lateral, sag, offset joint,
missing pipe, etc. Pipe shall be as specified herein and installed at the locations shown on the
Drawings.
1.02 SUBMITTALS
A. The Contractor shall submit for approval by the Engineer the following information:
B. Manufacturer's literature on the materials identified below. Literature shall include recommended
installation procedures.
C. Certification by the manufacturer that all pipe and fittings furnished under this specification were
manufactured, sampled, tested, and inspected in accordance with ASTM C700 and ASTM C301.
1.03 MATERIALS
A. Vitrified Clay Pipe: ASTM C700 Extra Strength, unglazed; Bell and Spigot Type and Fittings per
ASTM C425. Gladding, McBean & Co., or approved equal.
B. Couplings: Rubber or elastomeric PVC flexible, shielded couplings with stainless steel screws,
nuts, housings, and anti-radial shear (ARC)bands. Mission Rubber Company "Calder Style
Coupling", Fernco Inc. "Shielded Coupling" or approved equal.
C. Stoppers: Vitrified Clay or Plastic.
Each length of vitrified clay pipe shall be marked with the manufacturer's name or trademark, the
location of the plant, and the words "Extra Strength" or the symbol "ES."
Wye fittings shall be furnished with spurs already securely fastened by the manufacturer to the
barrel of the pipe. There shall be no projection on the inner surface of the pipe barrel. The axis
of the spur on the fitting shall be 45-degrees from the longitudinal axis of the pipe. Tee fittings
are unacceptable.
Stoppers furnished for installation in branch fittings and ends of pipe left unconnected shall
sustain all applied construction and in-place loads, including field pressure tests.
1.04 JOINING AND INSTALLATION
Pipe and fittings shall be handled, joined, and installed in accordance with the printed instructions
and recommendations of the pipe manufacturer. Joint contact surfaces shall be cleaned immediately
prior to joining. Use joint lubricants and joining methods recommended by the pipe manufacturer.
Unless otherwise specified, lay all pipe straight between changes in alignment and at uniform grade
between changes in grade. Pipe bedding shall provide uniform and continuous support of the pipe
barrel. Excavate bell holes for each pipe joint.
VITRIFIED CLAY SEWER PIPE SECTION 2731
CITY OF PALO ALTO Section 2731 PAGE 2
The laying of the pipe shall be in finished trenches free from water or debris. Start pipe laying at the
lowest point and install the pipe so that the spigot ends point in the direction of flow to prevent
bedding material from entering the joint. After each pipe has been brought to grade, aligned, and
placed in final position, deposit and shovel slice or spade bedding material under the pipe haunches.
No wedging or blocking to support the pipe will be permitted.
Every precaution shall be taken to prevent foreign material from entering the pipe during installation.
No debris, tools, clothing, or other materials shall be placed in the pipe. Whenever pipe laying is
stopped, the open end of the pipe shall be closed with an end board closely fitting the end of the pipe
to keep sand and earth out of the pipe. The end board shall have several small holes near the
bottom to permit water to enter the pipe and prevent flotation in the event of flooding of the trench.
When an existing VCP sewer main pipe is entering or leaving a newly constructed manhole,
Contractor shall replace in kind, a small section of new VCP pipe and connect to the existing VCP
pipe with a Anti-Radial (ARC) flexible coupling. Contractor shall remove the bell by making straight
cuts on both sides of new VCP pipe, refer to standard detail WWD-07B & 08B for specifications on
pipe length.
1.05 TESTING
The pipe shall be tested with low pressure air in accordance with ASTM C828. Wyes shall be
plugged during test. Any newly installed or replaced sewer lateral along the pipe shall also be tested
by setting the plug at the cleanout location. Tests shall be made in the presence of the Contractor
and the Engineer.
If the pipe fails the air test, the Contractor shall locate the source(s) of the leak and repair the
defect(s) or relay the pipe, as necessary. The pipe shall then be retested until a satisfactory result is
obtained.
Despite any previous testing, any leaks developed before the end of the 1-year guarantee period
shall be expeditiously repaired by the Contractor at no expense to the City.
1.06 CLEANING AND VIDEO INSPECTION
After installation, pipe and structures shall be cleaned and video inspected in accordance with the
Project Specifications and Section 2739, “Cleaning and Video Inspection of Sewer Pipe” of these
Standards. The Contractor shall repair all defects or relay the pipe, as necessary.
END OF SECTION
POLYVINYL CHLORIDE SEWER PIPE SECTION 2733
CITY OF PALO ALTO Section 2733 PAGE 1
SECTION 2733
POLYVINYL CHLORIDE SEWER PIPE
1.01 SCOPE
This section covers installation of new polyvinyl chloride sewer pipe (PVC) for spot repairs to match
existing pipe. Pipelines shall be as specified herein and installed at the locations shown on the
Drawings.
1.02 SUBMITTALS
The Contractor shall submit for approval by the Engineer the following information:
A. Manufacturer's literature on the materials identified below. Literature shall include recommended
installation procedures.
B. Certification by the manufacturer that all pipe and fittings furnished under this specification were
manufactured, sampled, tested, and inspected in accordance with the specified standards. The
date the pipe was manufactured shall be included in the Certification.
1.03 MATERIALS
Sewer pipe and fittings shall meet the following minimum requirements.
A. PVC Pipe & Fittings:
1. PSM SDR 26 PVC Sanitary sewer pipe that meets the requirements of ASTM D3034. Pipe
shall have elastomeric gasket joints that are oil resistant and conform to ASTM F477. (For 4
to 12 inch pipes).
2. AWWA C900, PR 200, DR 14 (for 4 to 12 inch pipes) unless noted otherwise on the
Drawings.
3. AWWA C905, PR 235, DR 18 (for 14 inch or larger pipes) unless noted otherwise on the
Drawings.
Couplings: Anti-Radial Shear “Calder-Style” flexible couplings. Flexible couplings with
mechanical clamps shall be used to connect two plain end PVC pipes of the same OD. PVC
pipe and fittings shall be manufactured in a one-piece mold with injection PVC compound
conforming to ASTM D1784, class 12454 B. Bells shall conform to ASTM D3139 as measured in
accordance with ASTM D2122 and gaskets shall conform to ASTM F477.
All PVC pipes shall be white or green. Contractors shall mark all PVC pipes with 3"-wide
(minimum) green color marking tape 12” above pipes which says ‘Sewer Pipe’ across the length
of the pipes. Each length of polyvinyl chloride pipe and each PVC fitting shall be marked with:
1. The nominal size and OD base.
2. PVC.
3. Dimension ratio number (for example, DR14).
4. The AWWA pressure class or rating (for example, PC200 or PR 200). (If applicable)
5. The AWWA designation number (for example, AWWA C900). (If applicable)
6. The manufacturer's name or trademark and production record code.
1.04 JOINING AND INSTALLATION
POLYVINYL CHLORIDE SEWER PIPE SECTION 2733
CITY OF PALO ALTO Section 2733 PAGE 2
Pipe and fittings shall be handled, joined, and installed in accordance with the printed instructions
and recommendations of the pipe manufacturer. Joint contact surfaces shall be cleaned immediately
prior to joining. Use joint lubricants and joining methods recommended by the pipe manufacturer.
Lubricant used for field assembly of gasketed PVC pipe shall have no detrimental effect on the
gasket, joint, fitting or pipe.
Unless otherwise specified, lay all pipe straight between changes in alignment and at uniform grade
between changes in grade. Pipe bedding shall provide uniform and continuous support of the pipe
barrel. Each length of pipe shall be laid on compacted, standard bedding material as specified and
shall have full bearing for its entire length between bell holes excavated in said bedding material to
allow for unobstructed assembly of all bell and spigot joints. Do not insert pipe past the reference
mark. Stabbing, swinging-in, or popping-on spigot ends of pipe into bell ends will not be permitted.
After jointing is accomplished, all annular spaces between pipe and bell holes shall be packed with
bedding material, taking care not to damage, move, or lift the pipe from its bedding support.
The laying of the pipe shall be in finished trenches free from water or debris. After each pipe has
been brought to grade, aligned, and placed in final position, deposit and shovel-slice or spade
bedding material under the pipe haunches. No wedging or blocking to support the pipe will be
permitted.
Every precaution shall be taken to prevent foreign material from entering the pipe during installation.
No debris, tools, clothing, or other materials shall be placed in the pipe. Whenever pipe laying is
stopped, the open end of the pipe shall be closed with an end board closely fitting the end of the pipe
to keep sand and earth out of the pipe. The end board shall have several small holes near the
bottom to permit water to enter the pipe and prevent flotation in the event of flooding of the trench.
Where the pipe connects with the outside face of a manhole wall or the wall of any other structure, a
pipe joint or coupling shall be provided a maximum of 12" from the face of the wall such that slight
flexibility or motion can take place in or near the plane of the wall face.
All PVC pipe entering or leaving a concrete structure shall have a rubber sealing gasket, as supplied
by the pipe manufacturer, firmly seated perpendicular to the pipe axis, around the pipe exterior and
cast into the structure base or centered in the manhole wall as a water stop. The water stop shall be
firmly fitted around the pipe exterior. Said water stop may also consist of a manhole coupling with
rubber sealing rings cast into the structure base.
1.05 DEFLECTION
The inside diameter of an installed section of flexible pipe shall not be allowed to deflect more than
five (5%) percent. All PVC solid wall flexible pipe shall be checked by means of a pipe deflection
gauge in the presence of the Engineer after the placement of all trench backfills, aggregate subbase
(if specified) but prior to installation of aggregate base and/or asphalt concrete. The deflection
standard will also be applied to installed pipelines prior to the expiration of the 12-month warranty
period.
The pipe deflection gauge shall be fabricated to permit passage through installed sections of
pipelines within the specified tolerances for the applicable plastic pipe and the maximum deflection
set forth herein. The pipe deflection gauge shall have at least 9 legs, and the number of legs shall be
odd. Any section or sections of plastic pipe that does not permit deflection gauge passage will not be
accepted and said section or sections shall be properly repaired or replaced and rechecked as
directed by the Engineer. Re-rounding through the use of a vibratory machine will not be permitted.
1.06 TESTING
POLYVINYL CHLORIDE SEWER PIPE SECTION 2733
CITY OF PALO ALTO Section 2733 PAGE 3
The installed pipe shall be tested with low pressure air in accordance with ASTM C828. Test shall be
made in the presence of the Contractor and the Engineer. If the pipe fails the air test, the Contractor
shall locate the source(s) of the leak and repair the defect(s) or relay the pipe, as necessary. The
pipe shall then be retested until a satisfactory result is obtained. Despite any previous testing, any
leaks developed before the end of the 1-year guarantee period shall be expeditiously repaired by the
Contractor at no expense to the City.
1.07 CLEANING AND VIDEO INSPECTION
After installation, pipe and structures shall be cleaned and video inspected in accordance with
Section 2739, “Cleaning and Video Inspection of Sewer Pipe.” The Contractor shall repair all defects
or relay the pipe, as necessary.
END OF SECTION
SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 1
SECTION 2735
SEWER CONSTRUCTION WITH POLYETHYLENE PIPE
1.01 GENERAL
A. Scope: This section covers the installation of new high density polyethylene sewer pipe (HDPE)
by pipe bursting or open trench method (if applicable). Pipe shall be as specified herein and
shall be installed at the locations, and using the methods, indicated on the Drawings.
B. General Bid Requirements (for CIP Projects containing pipe bursting or open trench)
Qualifications of Bidders:
1. All sewer main installation work by open trench method shall be performed by an
experienced contractor or subcontractor who has completed at least 10,000 feet of 8-inch in
diameter or larger pipes within the last three years.
2. All sewer main installation work by pipe-bursting method shall be performed by an
experienced contractor or subcontractor who meets the following qualification:
a. The contractor or subcontractor shall have completed at least three projects in the last
five years, involving pipe-bursting installation of a combined total of 20,000 feet or more
of 8 to 22 inches (O.D. of new pipe) pipes in diameter.
b. The contractor or subcontractor shall have completed projects involving pipe-bursting
installation of a combined total of 5,000 feet or more of 24 inches (O.D. of new pipe) or
larger pipes in diameter. (Note: This requirement is only applicable for project scope
involving 24” or larger pipes.)
c. The project on-site superintendent and/or on-site foreman shall each have at least
10,000 feet and three years experience involving pipe-bursting installation on 8 inches
(O.D. of new pipe) or larger pipes. The on-site superintendent and/or on-site foreman
shall not be removed or replaced from the project without written permission from the
City. The replacement person shall also meet the required qualification.
d. The contractor shall submit the pipe-bursting operator’s certification of training by the
pipe bursting system manufacturer. The operator shall be trained in the use of the pipe
bursting equipment by an authorized representative of the manufacturer. Training shall
include handling and installation of pipe and use of equipment.
3. All sewer lateral installation work by open trench method shall be performed by an
experienced contractor or subcontractor who has completed at least 1,000 feet of 4-inch in
diameter or larger pipes within the last three years.
4. All sewer lateral installation work by pipe-bursting method shall be performed by an
experienced contractor or subcontractor who has completed at least 15,000 feet of 4-inch in
diameter or larger pipes within the last three years
The following data shall be submitted with the bid, using the City-provided form #2735-1,
for the company and staff experience with open trench construction:
SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 2
Contractor/Subcontractor Open Trench Construction Experience
x Name of Contractor and/or Subcontractor.
x Name of project and year of construction.
x Project location and project dollar amount.
x Owner, owner contact, and phone number.
x Total footage and size of open trench construction experience as described above on 8 inch
or larger pipe.
The following data shall be submitted with the bid, using the City-provided form #2735-2,
for the staff experience with open trench construction:
On-site Superintendent and/or Foreman Open Trench Construction Experience
x Full name.
x Years of pipe-bursting experience.
x Name, location, year, owner, owner contact information of the referenced project(s).
x Total footage of open trench construction experience on 8 inch or larger pipe.
The following data shall be submitted with the bid, using the City-provided form #2735-3,
for the company experience with pipe-bursting construction:
Contractor/Subcontractor Pipe-Bursting Experience
x Name of Contractor and/or Subcontractor.
x Name of project and year of construction.
x Project location and project dollar amount.
x Owner, 2wner contact, and phone number.
x Total footage and size of pipe-bursting experience as described above for 8 to 22 inch (O.D.
of new pipe) pipe.
x Total footage and size of pipe-bursting experience as described above for 24 inch (O.D. of
new pipe) or larger pipe. (Note: This requirement is only applicable for project scope
involving 24” or larger pipes.)
The following data shall be submitted with the bid, using the City-provided form #2735-4,
for the staff experience with pipe-bursting construction:
On-site Superintendent and/or Foreman Pipe-Bursting Experience
x Full name.
x Years of pipe-bursting experience.
x Name, location, year, owner, owner contact information of the referenced project(s).
x Total footage of pipe-bursting experience on 8 inch or larger pipe.
5. Patents: The Contractor shall assume all costs arising from the use of any pipe-bursting
patented materials, equipment, devices, or processes used on or incorporated in the work,
and agrees to indemnify and save harmless the City of Palo Alto and its employees, and
their duly authorized representatives, from all suits at law, or actions of every nature for, or
on account of the use of any patented materials, equipment, devices, or processes.
The City’s purchasing manager in conjunction with the City’s project manager shall
determine whether the Contractor that is otherwise the lowest responsive bidder, meets the
experience and qualification criteria and shall notify the Contractor in writing of a
determination that it does not meet the criteria. The Contractor may dispute this
SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 3
determination by delivering written notice to the city’s purchasing manager within 5 business
days of receipt of the City’s notice of disqualification. The determination shall be final if the
Contractor does not submit a notice requesting a hearing within this time period. The notice
shall request a hearing and set forth the grounds on which the Contractor disputes the City’s
determination. Upon receipt of the Contractor’s notice an informal hearing shall be
scheduled with the City Manager or designee at which the Contractor will be given the
opportunity to present information and the reasons for disputing the determination that it
does not meet the qualification and experience criteria. The decision of the City Manager or
designee shall be final.
1.02 SUBMITTALS
The Contractor shall submit for approval by the Engineer the following information:
A. Manufacturer’s literature on the materials and equipment.
B. Certification by the manufacturer that all pipe and fittings furnished under this specification were
manufactured, sampled, tested, and inspected in accordance with the latest version of ASTM
F714-85 and ASTM D3350 (for cell classification). Certification shall be signed by an authorized
agent of the manufacturer. A report of test results shall be furnished if requested by the
Engineer. The date the pipe was manufactured shall be included in the Certification.
C. Pipe bursting operator’s training certification by an authorized representative of the equipment
manufacturer.
D. Fusion Certifications by City of Palo Alto – provide names and copies of cards issued to all
operators.
E. Access pit locations.
F. Access to Contractor’s Datalogger Vault.
G. Flow bypass plan, if applicable.
1.03 MATERIALS AND EQUIPMENT
Sanitary sewer materials shall meet the requirements of this section, Standard Specifications Section
2300 ‘Polyethylene Pipe Installation for Water, Gas, Wastewater’, and Standard Specifications
Section 2737 ‘Sanitary Sewer Lateral’.
A. Service Saddles: All service saddles shall be electrofusion type saddles by Central, Frialen by
Friatec, or approved equal.
B. Pipe Bursting Equipment: Equipment manufacturers have developed a vast array of different
tools and equipment to meet the wide variety of demands for pipe bursting projects. Pneumatic
and static pipe bursting are the two primary methods of pipe bursting projects performed in North
America. Contractors shall select pipe bursting equipment based on project design application,
pipe material to be installed, clearance to adjacent or crossing utilities, soil conditions, noise, risk
mitigation, etc. Static pipe bursting equipment shall be used to avoid damage where existing
underground pipes are in proximity.
SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 4
a. Pneumatic Pipe Bursting
1. Winch Assembly
2. Pneumatic “Hammer” Pipe Bursting Tool & Expander Head
3. Air Compressor and Hose Assembly
b. Static Pipe Bursting
1. Static machine Assembly
2. Rod, Cable, chain & Expander Head
3. Series of Cutters, Splitters, or other tools placed in front of expander head
C. Pipe and Fittings: SDR-17 Extra High Molecular Weight, High Density Polyethylene PE 4710,
Cell Class PE445574C/E (inner wall shall be white or light in color) per ASTM D3350 in IPS
sizes. Performance Pipe “DriscoPlex 4600” with four (4) equally spaced green single stripes or
approved equal.
The pipe shall contain no recycled compound except that of which is generated in the
manufacturer’s own plant from resin of the same specification, from the same raw material type.
Pipe and Fittings shall be homogeneous throughout and free of:
a. Serious abrasion, cutting, or gouging of the outside surface extending to more than 10
percent of the wall thickness in depth.
b. Cracks
c. Kinking (generally due to excessive or abrupt bending)
d. Flattening
e. Holes
f. Blisters
g. Other injurious defects
Pipe and fittings shall be uniform in color, opacity, density, and other physical properties. Any
pipe and fittings not meeting these criteria shall be rejected.
The average outside diameter and wall thickness of pipe and fittings shall conform to Table 1
when measured in accordance with ASTM D2122, D3035, D3350 (cell 445574C).
TABLE 1
Nominal Size
(inches)
Nominal OD
(inches)
Minimum Wall Thickness
SDR17 (inches)
4 4.500 0.265
6 6.625 0.390
8 8.625 0.507
10 10.750 0.632
12 12.750 0.750
SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 5
TABLE 1
Nominal Size
(inches)
Nominal OD
(inches)
Minimum Wall Thickness
SDR17 (inches)
14 14.000 0.824
16 16.000 0.941
18 18.000 1.059
20 20.000 1.176
22 22.000 1.294
24 24.000 1.412
26 26.000 1.529
28 28.000 1.647
30 30.000 1.765
32 32.000 1.882
34 34.000 2.000
36 36.000 2.118
42 42.000 2.471
D. Pipe Markings
Pipe shall be marked at 3-foot intervals or less with the manufacturer's name (or trade mark), the
designation ASTM F714 and ASTM D3350 , including the year of issue, the letters "PE" followed
by the cell classification number of the raw material compound used, the nominal pipe size in
inches, the dimensional ratio, and the manufacturer's code identifying the resin manufacturer, lot
number, and date of manufacture.
All sewer pipes shall have a white or light gray interior and have an exterior color of either black
or gray. Additionally, the exterior pipe shall be color identified by four (4) longitudinal green
stripes evenly spaced. The pipes shall be properly stored and handled in accordance with the
manufacturer’s recommendations and shall be less than two (2) years old at the time of
installation. Contractor shall factor in lead times for ordering compliant pipe to meet project
requirements.
Fittings shall be marked with the manufacturer's name (or trademark), the designation ASTM
D3350 and ASTM F714, and the manufacturer's code identifying the resin manufacturer, lot
number, and date of manufacture.
E. Electrofusion Couplings: Electrofusion couplings shall be manufactured by Friatec (Frialen
Safety Fittings). Any other electrofusion manufacturer such as Central, Kerotest (Innogaz
Electrofusion Products) or equal must receive prior approval. Electrofusion couplings to join
sewer mains shall only be used upon Engineer’s approval.
F. Other Equipment
Butt Fusion Machine: McElroy Manufacturing, Inc. or approved equal.
Electrofusion Machine: Central, Friatec, or approved equal.
SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 6
External and Internal Bead Removers: McElroy Manufacturing, Inc. or approved equal.
Pulling or Pushing Head: Driscopipe, Plexco or approved equal.
1.04 JOINING AND INSTALLATION
Subsurface Condition: Refer to Invitation for Bid (IFB) Package Part 2 – Instructions to Bidders
Section 17.0 for subsurface condition.
A. Pipe Bursting
1. Access Pits: Access pit locations shall be chosen and recommended by the Contractor with the
intent of minimizing excavation and traffic disruption. Recommended locations shall be at
service connections, manhole construction, or at points where repairs need to be performed. The
Contractor shall submit the number, location, and size of pits to Engineer for review prior to start
of the work.
The access pits shall be excavated to allow adequate width for access of workers, sheeting and
shoring installation, and to provide clearance necessary to avoid damage to the main during
installation. Care shall be taken to protect existing utilities.
The minimum length of each access pit as measured at the bottom of trench shall be determined
by the formula, Length = (12 x Outside Diameter of the liner in feet) + (2.5 x Depth of the trench
in feet).
2. Joining: Pipes shall be joined to one another and to plastic fittings by thermal butt-fusion, in
accordance with ASTM D2657, or by automatic electrofusion. Operators of fusion equipment
must pass qualification testing by the City of Palo Alto Utilities Department prior to performing
any fusion work. Time and temperature of fusion shall be per the manufacturer's
recommendation. Weld on flanges may be used to join pipes in access pits if approved by the
Engineer. Joints shall be stronger than the pipe itself, be properly aligned, and contain no gaps
or voids. Bead projections on the inside of the pipe shall be removed. No rubber couplings are
allowed on mainlines, unless approved by the Engineer.
3. Insertion of the new pipe: The pipe shall be supported on rollers throughout its entire length
during insertion. Dragging of the pipe along the ground during insertion will not be permitted.
4. Pipe Bursting: To ensure structural integrity and reduce risk for future leaks, installation of
unnecessary electrofusion or mechanical couplings should be avoided. Accordingly, with respect
to sewer mains with upstream and downstream manholes that are within 500 linear feet apart,
the use of couplings is not allowed, unless approved by the Engineer for unavoidable
circumstances. The Contractor shall plan and schedule the pipe-bursting work to replace each
reach of sewer main from manhole to manhole completely in one working day during the work
hours. The Contractor shall schedule all pipe-bursting preparation work and adjust the bursting
speed to meet all requirements. The Contractor should include the cost to use ‘pre-burst’ or
‘double-pull’ method, if deemed necessary to successfully replace the sewer main and meet all
requirements. The use of lubricant mud to reduce the friction is allowed when hard and very
dense soil is encountered.
SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 7
The Contractor shall also expose the main, at every lateral connection to a depth equal to 1 x the
outside diameter of the main, under the invert of the existing main to allow free movement of the
bursting head.
If there is no adequate staging area to store the entire reach of fused-pipe, the Contractor shall
perform fusion work to connect two or three previously fused-pipe segments on the day of pipe-
bursting. The Contractor shall allow an additional 30-minute cool-down time for each fused-joint
before rough-handling or resuming pipe-burst operation. Internal beads at pipe joints can only be
left in place, with Inspector’s approval, when it is not feasible to fuse the entire reach of pipe prior
to pipe-bursting. Only one internal bead for every 200 feet of pipe is allowed.
If a manhole at one end of the pull is not intended to be replaced, the Contractor shall use the
appropriate equipment utilizing a hydraulic or pneumatic head to pull into a manhole without
disturbing the surrounding area of the manhole.
The pipe bursting tool shall make a tunnel along the path formerly occupied by the old sewer and
shall install the new pipe by pneumatic or static method, or a combination of both. The pipe-
bursting tool shall be of the type and size recommended by the tool manufacturer for the size of
pipe being burst and for the existing ground conditions. The Contractor shall use lubricating
fluids, such as bentonite or polymer slurry, injected behind the bursting head for pipe diameters
greater than 16”. Lubricating fluids can also be used if hard/dense soil condition is encountered.
The Contractor must clean the lubricant mud from the pipe at each lateral connection for proper
fusion saddle adhesion.
When the tool is pulled along the existing pipe, the pipe shall be broken up into small fragments
and these fragments driven into the surrounding pipe zone. The tool shall then install the new
pipe by pulling it into place.
The new sewer main shall be installed without any horizontal or vertical offsets. The invert of the
new sewer pipe should match the invert of the existing sewer at the exit of the upstream manhole
and at the entrance into the downstream manhole, regardless of the size and alignment of the
existing pipe.
The Contractor shall allow the new HDPE pipe to return to its original length and shape in the
unstressed state and then trim the excess pipe in the manholes. The HDPE pipe manufacturer's
recommendations shall be followed regarding the relief and normalization of stress and strain
due to temporary stretching or elongation after pulling operations are completed. Time allowed
for stress and strain relief shall not be less than 24 hours.
A minimum of three working days prior to pipe bursting mains or laterals, the Contractor shall
pothole, at minimum, all utility pipes crossing the pipe bursting alignment where the invert of the
existing sewer main being replaced is 6 feet deep or less. In addition, Contractor shall pothole
crossings with ACP water mains and primary electric lines/duct bank where the invert of the
existing sewer main being replaced is 8-1/2 feet deep or less.
Potholed utility pipes shall be fully exposed during pipe bursting for the Inspector to observe
while the new sewer main is passing under the potholed pipes. The pothole excavation shall be
extended to 1 foot below the bottom of crossing pipes and 2 feet below the bottom of crossing
ACP water mains or primary electric lines/duct bank. The contractor is responsible for all costs
resulting from damage to utilities during pipe bursting operations.
SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 8
The upsizing method shall not cause excessive disruption to the above ground terrain or
improvements except for at the launching and receiving pits.
5. Service Connections: After the pipe has been pulled into place, the Contractor shall allow the
pipe to relax before cutting the ends of the new main or the lateral connection holes. The rest
period for the pipe shall be at least 24 hours and shall comply with pipe manufacturer’s
recommendation. The Contractor shall reconnect or replace all active sewer laterals along the
new main within 2 business days after the new pipe has been relaxed.
Electrofusion saddles shall be installed per Utility Standard Details for service connections.
B. Open Trench
1. Trench Excavation: The trenches shall be excavated to allow adequate width for access of
workers, sheeting and shoring installation, and to provide clearance necessary to avoid damage
to the main during installation. Care shall be taken to protect existing utilities. Refer to Utility
Standards Section 2200 3.4 for additional requirements.
2. Installation of the new main: Complete length of pipe from manhole to manhole, free of any
couplings (mechanical or electro-fusion), with exception to service connections at the main.
3. Service Connections: The Contractor shall reconnect or replace all active sewer laterals within
2 business days after the new main is installed. New sewer pipe shall be installed without any
horizontal or vertical offsets. Unless otherwise noted, the invert of the new sewer pipe should
match the invert of the existing sewer at the exit of the upstream manhole and at the entrance
into the downstream manhole, regardless of the size and alignment of the existing pipe.
Electrofusion saddles shall be installed per Utility Standards Details for service connections.
1.05 TESTING
A. Air pressure setup shall be in accordance with ASTM F1417, Constant Pressure Method. The
pipe shall be tested with low pressure air at 3.5 psi for 5 minutes with NO pressure loss. Wyes
shall be plugged during test. Tests shall be made in the presence of the Contractor and the City
Inspector or Engineer.
B. If the pipe fails the air test, the Contractor shall locate the source(s) of the leak and repair the
defect(s). The pipe shall then be retested.
C. TV Inspection: After passing the air test, both laterals and mains shall be CCTV per Section
2739, Cleaning and Video Inspection of Sewer Pipe.
D. Any pipe defects identified before the end of the 1-year guarantee period shall be expeditiously
repaired by the Contractor at no expense to the City.
1.06 CLEANING AND VIDEO INSPECTION
A. Initial Cleaning and Video Inspection
Prior to replacing the sewer mains, the Contractor shall clean and video-inspect the existing
sewer mains. Based on the lateral connections to the main observed from the video inspection,
the Contractor shall accurately identify all active sewer laterals and verify each active lateral’s
SEWER CONSTRUCTION WITH POLYETHYLENE PIPE SECTION 2735
CITY OF PALO ALTO Section 2735 PAGE 9
location and/or alignment. The cost to identify active sewer laterals shall be included in one or
more bid items.
B. Final Cleaning and Video Inspection
After installation, pipe and structures shall be cleaned and video inspected in accordance with
Project Specifications and the current Water Gas and Wastewater Utility Standards. The
Contractor shall repair all defects at no additional cost to the City.
END OF SECTION
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CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 1
SECTION 2736
CURED-IN-PLACE PIPE (CIPP)
1.01 GENERAL
A. Scope
This section covers the installation of cured-in-place pipe (CIPP) rehabilitation of existing sewer
pipe. The cured pipe shall be as specified herein and installed at only the locations approved by
the engineer and shown on the Drawings.
B. General Bid Requirements:
1. The Contractor, or his/her CIPP Sub-contractor, shall clean and remove all debris, including
any degree of root infiltration, using the recommended cleaning method for pipe cleaning as
specified in Section 2739, to return host pipe back to CIPP manufacturer’s recommended
parent host pipe condition for installation of CIPP lining.
2. The Contractor, or his/her CIPP Sub-contractor, shall repair and/or prepare host pipe using
methods recommended by the CIPP manufacturer, not limited to chemical grouting or
sectional pipe spot repair.
3. The Contractor and his/her CIPP Sub-contractor, must factor in ambient conditions which
may affect properties related to the CIPP materials, such as site and weather conditions
during installation. Scheduling of CIPP material procurement, proper and feasible
accessibility of CIPP on-site mobilization and understanding of proper handling of uninstalled
CIPP material properties on site may affect the CIPP installation. Supplier scheduling,
material procurement, bypass setup & spill mitigation plan, and site assessment
responsibilities shall be factored into the proper CIPP installation process.
4. Refer to Water, Gas, and Wastewater Utility Standards Section 2730 for requirements of flow
bypass plan.
5. The curing and installation methods of the liner shall be described and included with the Bid.
The Contractor shall demonstrate that the method is applicable and that his/her experience
in using the method is proven.
6. The Contractor, or his/her CIPP Sub-contractor, shall be properly licensed and trained to a
cured-in-place pipelining process having of a combined total of 20,000 lineal feet of
successful installation in the United States within the last two (2) years, in pipelines ranging
from 8 to 48 inches. Documentation of the licensing and details of two (2) years minimum
training of the on-site superintendent and foreman of the Contractor, or his/her CIPP Sub-
contractor, performing the actual installation, shall be submitted, using the City-provided
forms #2736-1 and #2736-2 (use multiple sheets if necessary), with the Bid.
C. Process Description
Installation of the Cured-In-Place Pipe shall be accomplished by the use of an inversion process
or a winched-in application. The reconstruction of the existing line shall be accomplished by
installing a flexible liner which is first impregnated with a thermosetting resin. The liner is either
inverted into the pipeline by using hydrostatic head (water pressure), compressed air pressure or
some other approved inversion method, or pulled into the pipeline from manhole to manhole
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 2
using mechanical equipment (winch). After full insertion, the liner is cured by circulating hot
water, ultra-violet light or, introducing controlled air or steam throughout the length of the liner to
cure it into a hard, impermeable pipe. This “pipe” shall extend the full length of the original sewer
from manhole to manhole, and shall provide a structurally sounds, jointless, tight-fitting,
watertight pipe within a pipe.
D. References
The following documents form a part of these specifications to the extent stated herein and shall
be the latest edition thereof.
American Society for Testing and Materials (ASTM):
ASTM D 256 Standard Test Methods for Impact Resistance of Plastics and Electrical
Insulating Materials
ASTM D 543 Resistance of Plastics to Chemical Reagents
ASTM D 638 Tensile Properties of Plastics
ASTM D 732 Standard Test Method for Shear Strength of Plastics by Punch Tool
ASTM D 790 Flexural Properties of Unreinforced and Reinforced Plastics and Electrical
Insulating Materials
ASTM D 2990 Tensile, Compressive, and Flexural Creep and Creep-Rupture of Plastics
ASTM D 3567 Standard Practice for Determining Dimensions of “Fiberglass” (Glass-Fiber-
Reinforced Thermosetting Resin) Pipe and Fittings
ASTM D 5813 Cured-in-Place Thermosetting Resin Sewer Pipe
ASTM F 1216 Standard Practice for Rehabilitation of Existing Pipelines and Conduits by
the Inversion and Curing of Resin-Impregnated Tube (1991 Revision)
ASTM F 1743 Standard Practice for Rehabilitation of Existing Pipelines and Conduits by
Pulled-in-Place Installation of Cured-in-Place Thermosetting Resin Pipe
ASTM F 2019 Standard Practice for Rehabilitation of Existing Pipelines and Conduits by
Pulled-in-Place Installation of Glass reinforced Plastic (GRP) Cured-in-
Place Thermosetting Resin Pipe (CIPP)
ASTM F 2561 Standard Practice for Rehabilitation of a Sewer Service Lateral and Its
Connection to the Main Using a One Piece main and Lateral Cured-in-Place
Liner
National Association of Sewer Service Companies (NASSCO): Recommended Specifications for
Sewer Collection System Rehabilitation.
1.02 SUBMITTALS
The Contractor shall submit for approval by the Engineer the following information:
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 3
A. Engineering calculations for the design of the liner thickness. The design calculations shall be
checked and approved by a Registered Professional Civil or Mechanical Engineer in the State of
California. Liner design calculations shall be supported by field analysis, technical assumptions,
and section 1.03C, Liner Design Criteria, of this specification. Final approval of the design
calculations shall be given by the Engineer.
B. Certification from the installer that all lining materials and resins furnished under this specification
were manufactured, samples, tested and inspected in accordance with ASTM F 1216, latest
edition, “Standard Practice for Rehabilitation of Existing Pipelines and Conduits by the Inversion
and Curing of Resin-Impregnated Tube.”
C. Manufacturer's recommendations for the installation of the CIPP including resin application,
curing process details (including temperature control), storage procedures, service connection
methods, trimming and finishing, and quality control measures to be used for cured-in-place pipe
lining of main-lines and services.
D. Certification from the manufacturer(s) that the installer is licensed to perform the work.
E. Certification from the manufacturer(s) that the resin material complies with the required
application, meets the intended service condition, and that the resin will meet the physical
requirements set forth in this specification. Information from the resin manufacturer shall include
specifications, characteristics and properties of the resin, methods of application, curing
temperatures, and duration of temperature (step cooking temperatures/hours at each and final
stages).
F. Flow bypass plan.
G. Independent test laboratory results of field samples taken at locations specified by the Engineer.
Prior to construction, the Contractor shall provide the contact information for the third party
independent testing laboratory for approval.
H. The beginning and end of the pipe lining shall be cut flush at the inlet and outlet points in the
manhole. The ends shall be sealed to the rehabilitated pipeline. The sealing material shall be
compatible with the pipe liner and shall provide a watertight seal.
I. Air test service connection for water tightness after the main has been installed. Contractor shall
provide test process submittals for all sewer lateral connections for reinstatement, based on
CIPP manufacturer’s recommendations for all active sewer lateral connections (SLC) as
specified in Section 1.05.
1.03 MATERIALS
All materials and procedures used in the cured-in-place pipe rehabilitation process shall be equal to
or exceed the manufacturer's standards.
A. Liner: The liner tube shall be fabricated to meet performance requirements as specified in
section 1.03D, Finished and Cured Liner Properties, of this specification.
Fiber Felt Tube System: The felt tube shall be a thermoplastic polyester or acrylic tube
consisting of one or more layers of flexible needled felt or an equivalent woven and/or non-woven
material capable of carrying resin, and with sufficient needling and cross-lapping and strength to
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 4
withstand the installation pressures and curing temperatures. The felt tube to be furnished shall
be compatible with the resin and catalyst systems to be utilized. The tube shall be free of tears,
holes, cuts, foreign materials and other defects and will be subject to inspection by the City.
The finished lining shall consist of an inner plastic coating and outer polyester felt layer (or
layers) impregnated with a thermosetting resin and fabricated to fit tight against the existing pipe
wall. An allowance shall be made for circumferential stretching during inversion.
Contractor shall determine the minimum tube length necessary to effectively span the designated
run between manholes, unless otherwise specified. Contractor shall field verify the lengths in the
field prior to impregnation of the tube with resin, to ensure that the tube will have sufficient length
to extend the entire length of run.
B. Resin/Catalyst
The resin used shall be compatible with the rehabilitation process used and designed for a
wastewater environment. The resin shall be able to cure in the presence or absence of water,
and the initiation temperature for cure shall be as recommended by the resin manufacturer and
approved by the Engineer. The resin shall have sufficient thixotropic properties to obtain non-
draining characteristics when impregnated into the fiber fabric.
Unless otherwise specified or approved by the Engineer, the resin shall be a polyester system for
typical residential sewage and shall be able to meet the service conditions specified for the tube
system. For commercial, industrial, or other areas with a potential for sewage that affects
polyester, epoxy or vinyl ester resin shall be required as determined by the City.
The Engineer shall also be informed in advance, for verification and inspection of the resin
material at the "wet out" of the tube. The inspection shall be at the discretion of the Engineer,
which shall not relieve the Contractor of his responsibilities. The wet-out procedure shall utilize
the resin and catalyst in sufficient quantities to ensure complete impregnation of the liner and
provide the properties specified in Section 1.03D, Finished and Cured Liner Properties. The
installer shall provide qualified field personnel to ensure acceptable installation workmanship.
The catalyst system shall be compatible with the resin and other materials to be utilized in the
rehabilitation process. Quantity and type of catalyst shall be selected based on the curing
conditions and recommendations of the resin manufacturer.
C. Liner Design Criteria
The Cured-In-Place Pipe thickness shall be calculated and designed upon the following physical
conditions of the existing host pipe and per ASTM F1216, Appendix X.1:
1. All pipes shall be considered fully deteriorated.
2. All pipes shall be subjected to a soil load of 120 lbs./cu. ft., with applicable live load, and
water table two (2) feet below the top of the ground.
3. Pipes in good condition shall have a minimum of two percent (2%) ovality in the
circumference. A higher value of ovality shall be used if the pipe is deteriorated.
4. Factor of safety (N) of 2.0 shall be used for calculations.
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 5
Conditions 1 and/or 2 above may change after the initial CCTV report, if approved by the
Engineer. The Engineer shall have the right to modify/change the required liner thickness,
depending upon field conditions evident from the video footage and/or tested product values.
D. Finished and Cured Liner Properties
The finished cured-in-place pipe liner shall be white or light gray, fit tightly and neatly against the
existing pipe walls. The liner shall be fabricated from materials which, when cured, will be
suitable for continuous service in sewerage environments containing hydrogen sulfide, carbon
monoxide, carbon dioxide, methane, dilute (10%) sulfuric acid at an average wastewater
temperature of 80qF, dilute (10%) phosphoric acid, petroleum hydrocarbons, gasoline, vegetable
oil, tap water (pH 6.5 - 9), up to one (1) hour per day exposure to five percent (5%) sodium
hydroxide up to a pH of 11, moisture saturation, and external exposure to soil bacteria and
chemical attack which may be due to materials in the surrounding ground or sewage within. 0%
shrinkage allowed.
The cured-in-place pipe system shall conform to and comply with the requirements above, and
meet or exceed the minimum standard physical properties as follows:
STRUCTURAL/MECHANICAL
PROPERTY
ASTM
TEST
METHOD
ASTM
MINIMUM SHORT
TERM VALUE
ASTM
MINIMUM LONG
TERM VALUE
TENSILE STRENGTH (@ Yield) D-638 4,000 psi.
TENSILE MODULUS D-638 250,000 psi. 125,000 psi
FLEXURAL STRENGTH D-790 5,000 psi.
FLEXURAL MODULUS D-790 300,000 psi. 150,000 psi
SHEAR STRENGTH D-732 5,500 psi.
IMPACT STRENGTH D-256 1.9 in.-lb.
The initial stiffness factor shall conform to the following table:
1.Stiffness factor shall be determined in accordance with ASTM D2412.
2.Safety factor not included.
Nominal ID of
Original Pipe
(Inches)
Stiffness Factor (EI)1
(in3-lbf/in2)
Maximum Allowable Depth of
Groundwater Above Invert.2
(Feet)
6 328 238
8 328 96
10 328 48
12 328 27
12 1109 96
15 1109 48
18 1109 27
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 6
1.04 CURED-IN-PLACE PIPE (CIPP) LINER – MAIN INSTALLATION
The Contractor's operations to furnish and install the liner shall be in strict conformance with the
component materials and manufacturer's recommendations. The procurement of the CIPP liner,
ambient temperatures, weather, site accessibility and conditions, sewage bypass setup, and
mobilization to the project location are to be considered when the Contractor or subcontractor
schedules their sequence of work and the quality of the installation.
The host pipeline shall be cleaned and televised prior to CIPP installation. There will be debris
and/or root balls encountered that require the use of the appropriate cleaning method for their
removal to bring the host pipe to be within the parameters recommended for CIPP installation.
Where structural defects are present, the Contractor shall perform chemical grouting or point
repairs to the host pipe to ensure a successful liner installation. All protruding laterals encountered
during the pre-installation inspection shall be trimmed to be flush with the pipe interior as
practicable.
The Contractor or their CIPP subcontractor shall consider ambient temperatures, weather, and site
conditions which may affect physical or chemical properties of the CIPP liner when scheduling
work. The outside diameter of the liner being inserted shall be properly sized to allow for expansion
so that the CIPP liner can fit tightly against the host pipe.
The liner shall be installed through the existing manholes, in accordance with the manufacturer's
recommendations and procedures. The finished pipe on mainline reaches shall be continuous over
the entire length between manholes. A sealing material compatible with the liner shall be installed
at the entrance to each manhole between the liner and the existing pipe to provide a watertight
seal.
The Contractor shall submit to the Engineer a detailed plan of construction including the installation
procedures, equipment set-up, and the locations of the proposed access points for approval. The
Contractor shall have an approved plan of construction prior to commencing any construction.
During the curing process, the Contractor shall keep logs, charts and/or graphs of the liner
temperatures at the upstream and downstream manholes to ensure that proper temperatures and
cure times have been achieved. These documents may be requested by the Engineer at any time
during and after the curing process.
Immediately after curing of the tube and after the City’s acceptance of the hydrostatic exfiltration
testing, The Contractor shall proceed with the reestablishment of active wastewater connections to
the main in conformance with Section 2736, 1.05 “Reinstatement of Sewer Laterals”.
1.05 REINSTATEMENT OF SEWER LATERALS
Following the approval of the hydrostatic exfiltration test on the liner, the Contractor shall reinstate all
active sewer lateral connections (SLC) within 24-hours. Appropriate temporary flow control shall be
setup if needed, before the laterals are reinstated, to convey sewage and prevent sewer
backup/overflow.
The SLC is the interface between the sewer lateral and the sewer main. All SLC’s shall be exposed
without excavation using a City-approved remote-controlled cutting device. A backup remote-
controlled cutting device shall be kept on-site in case of malfunction. Where a SLC cannot be
reestablished using a remove-controlled cutting device, the Contractor shall notify the Engineer and
request approval to open-cut and reinstate the SLC.
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 7
When the SLC is exposed, the invert of the sewer lateral shall match the bottom of the reinstated
lateral opening. After exposing all active SLC’s, the Contractor shall perform CCTV inspection of the
main and laterals to locate damage or leaks. Laterals shall be inspected at a minimum of 16-inches
beyond the SLC.
Any infiltration found during CCTV-inspection shall be addressed by a SLC sealing system
requested by the Engineer. Any roots, protrusions, or debris found that will interfere with the SLC
sealing method shall be removed by the Contractor. If the inspection reveals an obstruction cannot
be removed by conventional sewer cleaning equipment, the Contractor shall be required to make a
point repair to excavate and remove the obstruction. The Contractor shall notify the Engineer prior
to the commencement of work.
When required, the Contractor shall divert sewage around section or sections of mainline pipe
where the SLC sealing is located. The wastewater lateral requiring a SLC sealing system shall be
inactive during the time of installation.
The SLC sealing method employed by the Contractor shall be one of the following methods and be
compatible with the main CIPP lining system.
A. Chemical Grout:
The lateral connection shall be sealed if the lateral connection does not pass the air test or
infiltration is visible. The Contractor shall use pressure inject chemical grout through a
lateral packer into the annual space between the lateral grouting plug and the lateral pipe.
Upon complete application of the chemical grout, the Contractor shall complete an air test.
If the SLC fails the air test, the Contractor shall repeat the grouting procedure at no
additional cost to the City.
Where grout blockage exists from grouting operations, the Contractor shall clear the lateral
at no additional cost to the owner.
B. Full-Wrap or “T-Style”:
The sealing material shall consist of a cured-in-place resin saturated felt tube that provides
a full-wrap liner in the mainline centered at the SLC with the liner extending at least 4-
inches into the lateral.
Installation shall conform to Section 7 of ASTM 2561. The installation method shall provide
an air-tight seal of the SLC sealing system to the mainline pipe and SLC. Prior to
installation, the felt tube shall be saturated with resin at the Work site and stored at the
temperature specified by the resin manufacturer. After installation, the felt liner shall be
cured as specified by the resin manufacturer. The SLC sealing tube for the lateral shall
extend a minimum of 4-inches from the mainline to the lateral.
After installation is complete and the SLC seal has cured, the Contractor shall perform
adhesion testing in conformance with Section 2736, Section 1.06 C. The Contractor shall
also perform an air pressure test on the cured SLC sealing system in accordance with
Section 2736, Section 1.06 D and submit all passing test results
C. “Brim Style”:
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 8
The sealing material shall consist of cured-in-place resin saturated fiberglass or felt
material that provides a brim section in the mainline with the brim centered around the SLC
with a liner section extending into the lateral. The length of the liner extending into the
lateral shall be a minimum of 4-inches from the mainline.
The fiberglass or felt material and liner shall be saturated with resin at the Work site and
stored at the temperature specified by the resin manufacturer. The resin saturated SLC
sealing system shall be loaded on an applicator apparatus, attached to a robotic device
and positioned in the mainline at the SLC to be sealed.
The robotic device shall be equipped with a CCTV camera which shall be used to align and
center the SLC sealing system within the lateral opening. The applicator apparatus shall
include a bladder or an approved mechanical device of sufficient length in the mainline and
lateral such that the inflated bladder or approved mechanical device extends beyond the
end of the SLC seal.
The insertion pressure shall be adjusted to fully deploy the SLC sealing system in the
lateral and hold the ends of the SLC seal ends against the pipe walls. The SLC sealing
system shall produce a smooth transition between the SLC seal and the pipe walls without
a ridge or gap between the SLC seal and the inner diameter of the mainline and the lateral.
Insertion pressure shall be maintained for the duration of the curing process. Curing shall
be as specified by the resin manufacturer.
After installation is complete and the SLC seal has cured, the Contractor shall perform
adhesion testing in conformance with Section 2736, Section 1.06 C. The Contractor shall
also perform an air pressure test on the cured SLC sealing system in accordance with
Section 2736, Section 1.06 D and submit all passing test results.
1.06 TESTING
A. Hydrostatic Exfiltration Test: The Contractor shall perform a hydrostatic exfiltration test on the
main after the inversion and curing of the liner but before the reinstatement of the laterals. This
test shall be performed to determine if the liner installation is watertight. This test shall be
performed in conformance with ASTM F1216. The test shall be conducted for a minimum of one
(1) hour.
B. Pipe Samples Testing: The Contractor shall prepare a minimum of one (1) CIPP sample for
testing for inversion in accordance with ASTM F1216 and ASTM F1743. Sample(s) shall conform
to the following two methods:
1. For host pipe diameters 18” and smaller, the sample should be cut from a section of cured
CIPP at an intermediate manhole or at the termination point that has been inverted through a
like diameter pipe which has been held in place by a suitable heat sink, such as sandbags.
2. For host pipes larger than 18” in diameter, the sample should be fabricated from material
taken from the liner and the resin/catalyst system used and cured in a clamped mold placed
in the down tube.
The samples for each of these cases should be large enough to provide a minimum of three
specimens. The samples shall be tested by a certified independent third-party testing laboratory
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 9
by the Contractor. The lab shall provide the Engineer for approval with certified test results. The
following test procedure shall be performed after the sample is cured and removed:
1. Short-Term Flexural (Bending) Properties – The initial tangent flexural modulus of elasticity
and flexural stress shall be measured for gravity and pressure pipe applications in
accordance with ASTM D790 and should meet the short-term flexural modulus and flexural
strength values used in the thickness designs of the CIPP previously submitted.
2. Wall thickness at any point shall not be less than 87.5% of the design thickness.
C. Lateral Chemical Grout Sealing Air Pressure Test: The joint testing pressure shall be equal to
0.5 psi per vertical foot to top of pipe depth plus 2 psi. Test pressures shall not exceed 10 psi
without approval of the Engineer. If pressure drop is found to be greater than 2 psi within 15
seconds, the application of grout shall be considered unsuccessful and the Contractor shall
repeat the grouting procedure and air testing procedure at no additional cost to the City.
D. SLC Sealing System Adhesion Testing: The adhesion testing shall be conducted after the
SLC seal has cured in accordance with the manufacturer’s specifications, but before the final
video inspection is performed. Adhesion testing shall consist of inserting a high velocity,
hydraulic cleaning type, 360-degree spinning nozzle and CCTV camera in the mainline pipe and
position the nozzle at the SLC seal. The water from the nozzle shall be directed downstream for
a minimum of 1 minute, at each edge of the SLC seal in the mainline at the minimum pressure of
1,500 pounds per square inch and a minimum flow rate of 65 gallons per minute.
E. SLC Sealing System Air Pressure Test: The cured SLC sealing systems shall be air pressure
tested. Test plugs shall be placed upstream and downstream of the SLC sealing system in the
mainline and, upstream of the SLC sealing system in the lateral. The test pressure shall be 4
pounds per square inch of a 3-minute test time during which the pressure shall not drop below
3.5 pounds per square inch. If the SLC sealing system fails this test, the test plug at the
upstream end of the lateral may be moved onto the SLC opening and the test conducted again. If
the second test passes, the SLC sealing system will be deemed to have passed the test.
1.07 CLEANING AND VIDEO INSPECTION
A. Initial Cleaning and Video Inspection
The existing sewer shall be cleaned and video inspected in accordance with Section 2739 of
these Specifications. The Contractor shall verify location of active lateral connections at this time.
B. Final Cleaning and Video Inspection
After CIPP lining is complete and the services have been reinstated, the pipe liner and SLC
sealing systems shall be cleaned and video inspected in accordance with Section 2739 of these
Specifications. The Contractor shall repair all defects at no additional cost to the City.
1.08 WARRANTY AND QUALITY ASSURANCE
A. The Contractor shall provide to the City a warranty to be in force and effect for a period of two (2)
years from the date of acceptance by the City. The warranty shall cause the Contractor to repair
or remove and replace the liner should failure result from faulty materials or installation.
CURED-IN-PLACE PIPE (CIPP) SECTION 2736
CITY OF PALO ALTO Section 2736 PAGE 10
B. Correction of failed liner or liner deemed unacceptable, as a result of the post video inspection
and/or test reports for structural values, thickness, chemical resistance, etc., shall always be the
responsibility of the Contractor, at no extra cost to the City. Method of correction/repair shall be
approved by the City with prior field demonstration, if required. It shall be understood that
minimum criteria of the specification shall not be lowered to compromise with lower than the
required test values, unless approved in writing.
C. The finished liner shall be continuous over the entire length of run between two manholes and
shall be free from visual defects such as foreign inclusions, dry spots, pinholes, and
delamination. The finished liner shall meet or exceed the requirements of Section 1.03D,
Finished and Cured Liner Properties.
D. Wrinkles in the finished liner pipe which exceed five percent (5%) of the pipe diameter are
unacceptable. Where this is visible in CCTV inspection footage, the Contractor shall mill down
the wrinkled segment below the spring line to be flush with the internal diameter of the newly
installed liner. Additionally, any wrinkles that traverse the invert and impede flow shall be
removed. Repair of the removed sections shall be proposed by the Contractor and approved by
the Engineer.
E. The Contractor shall carry out the operations in strict accordance with all applicable OSHA
regulations. Particular attention is called to those safety requirements involving work on an
elevated platform and entry into a confined space.
F. Where SLC sealing systems are installed and fail either the adhesion or the second air pressure
test, the Contractor shall be required to remove and replace or repair the SCL sealing system
G. The Contractor shall be required to perform post-construction CCTV inspection where chemical
grout is applied.
END OF SECTION
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SANITARY SEWER LATERAL SECTION 2737
CITY OF PALO ALTO SECTION 2737 PAGE 1
SECTION 2737
SANITARY SEWER LATERAL
1.01 SCOPE
This section covers installation of sewer laterals. Laterals shall be installed as specified herein and at
the locations shown on the Drawings.
1.02 SUBMITTALS
The Contractor shall submit for approval by the Engineer the following information:
A. Manufacturer's literature on the materials identified below. Literature shall include recommended
installation procedures.
B. Certification by the manufacturer that all pipe and fittings furnished under this specification were
manufactured, sampled, tested, and inspected in accordance with the standards specified herein.
The date the pipe and/or fittings were manufactured shall also be included in the Certification.
1.03 MATERIALS
Sanitary sewer lateral materials shall meet the requirements of this section, Section 2735 (Polyethylene
Sewer Pipe), and Section 2300 (Polyethylene Pipe Installation for Water, Gas and Wastewater).
1. HDPE Pipe: HDPE, SDR 17, 445574C D, or E as described in ASTM D3350. The HDPE pipe
shall have a white or light gray interior by Performance Pipe “DriscoPlex 4100” or approved
equal.
2. Flexible Anti-Radial Shear “ARC” Couplings: Neoprene flexible, shielded, anti-radial shear
coupling per ASTM C1173 with 300 series stainless steel clamp band, housing, screws, shield
and eyelet. Fernco Inc. "RC SERIES", or approved equal.
a. Note: All connections shall be made with butt fusion or electrofusion as specified in Section
2735 (Polyethylene Sewer Pipe) and Section 1.04 of this specification. Couplings will only be
allowed with prior approval of the Engineer for special circumstances.
3. Flexible Tap Saddles with Pressure Kit: Specially formulated high durometer PVC flexible
saddle with stainless steel clamps per ASTM D5926 by Fernco , Inc., or T-Flex Sewer Saddle by
Mission Rubber Co.
a. Note: Pressure Kit by Fernco, Inc. contains bentonite tape water seal, plastic-coated steel
reinforcing bars and stainless steel clamps. This kit creates a water tight seal on all four
sides of tap saddle.
4. T Cone Plugs: Expandable pipe plug with no metal parts by ETCO Specialty Products, Inc., or
approved equal.
5. Cleanout Box: Christy F08 curb valve box with F08C cast iron lid or G05T (Traffic Rated for
driveways and approaches) with G05CT cast iron lid or approved equal.
6. Elastomeric Sealant: High performance, one-part, polyurethane sealant. Vulkem 921 by
Tremco, or approved equal.
SANITARY SEWER LATERAL SECTION 2737
CITY OF PALO ALTO SECTION 2737 PAGE 2
Any pipe, fittings, or appurtenances that do not conform to the above specifications shall be rejected
and shall be removed immediately from the work site by the Contractor.
1.04 JOINING AND INSTALLATION
A. The Contractor is responsible for verifying an existing lateral’s horizontal and vertical alignment.
B. All new laterals shall be installed perpendicular to the main, at uniform slope, and without any
changes in lateral horizontal alignment or grade, unless otherwise approved by the Engineer.
Pipe bedding shall provide uniform and continuous support of the pipe barrel.
C. Lateral replacement by pipe bursting is allowed if the existing lateral meets the horizontal and
vertical alignment standards and the City-owned portion of the lateral is free of cross-bores. If
the existing lateral connection point at the main is more than five feet offset from the cleanout, as
measured on the field along the main, the Contractor shall abandon the existing lateral and install
a new lateral. The new lateral will be permitted to be installed at an angle to the main to avoid
utility conflicts or to establish a higher cleaning velocity. Pipe bursting requirements are specified
in Section 2735 Polyethylene Sewer Pipe.
D. All ACP laterals shall be replaced by open cut.
E. Pipe and fittings shall be handled, joined, and installed in accordance with the instructions and
recommendations of the pipe manufacturer.
F. If lubricant mud was used to replace the sewer main by pipe-bursting, extra precaution shall be
used to thoroughly clean the sewer main from lubricant mud at each service connection for
proper fusion saddle adhesion.
1.05 LATERAL CONNECTIONS
A. Lateral Connections to Mains
MAIN MATERIAL CONNECTION METHOD STANDARD DETAIL
HDPE ELECTROFUSION SADDLE WWD-05 DETAIL C
VCP CUT IN NEW VCP WYE WWD-05 DETAIL A
SDR26 PVC CUT IN NEW PVC WYE WWD-05 DETAIL A
C900 PVC STRAPPED RUBBER SADDLE WWD-05 DETAIL B
PCC / RCP TAP-TITE OR INSERTA-TEE WWD-06
1. Upon Engineer’s approval, “Tap-tite” or “Inserta Tee” can be used on existing C900 and
C905 PVC, SDR26 PVC, and VCP mains 10-inch and larger.
2. Existing PVC and ABS laterals in a condition acceptable to the City shall be reconnected to
new HDPE main using Electrofusion Saddle and Flexible Coupling. The assessment of the
lateral condition will be performed by CPA Wastewater Operations.
3. Special fittings for connection to sewer liner will be reviewed on a case by case basis.
B. Lateral Connections to Manholes
1. The preferred method of sewer lateral connection to existing manhole wall or base is core
drilling. Hammering of holes is acceptable but limited to a maximum size of sixty-pound
SANITARY SEWER LATERAL SECTION 2737
CITY OF PALO ALTO SECTION 2737 PAGE 3
jackhammers. The use of precision “chipping” equipment will only be acceptable with prior
approval from the on-site field Inspector.
2. Lateral crowns (top inside surface of the pipe) shall not be lower than the elevation of the
outlet main crown in the manhole, unless otherwise approved by the Engineer.
An appropriate manhole water stop gasket shall be used on all plastic pipe entering
manholes. For PVC and HDPE pipe, water stop gasket shall be Newby Rubber, Inc., Mission
Rubber, or approved equal.
3. Channel bottoms shall be worked to provide a smooth flowing transition from the new laterals
to the outlet channel. See Section 2738 (Precast Concrete Manholes) for outside drop piping
requirement.
4. Pipe penetrations shall be sealed with a non-shrink grout.
A. Cleanouts
1. A sanitary sewer cleanout shall be provided in the planting strip or in the case where the
sidewalk and curb are integral, at the back of sidewalk.
2. A T Cone Plug shall be used to plug the cleanout. T-Cone Plugs shall not be over tightened.
Plugs shall be tightened just enough to hold the plug in place and prevent inflow into the
pipe.
B. Inspection: All lateral connections shall be inspected and approved by the Utilities Inspector.
Applicants or developers shall schedule the inspection of new lateral connections at least one
week in advance.
1.06 SEWER LATERAL ABANDONMENT PROCEDURE
A. Excavate and disconnect the existing lateral at the main.
1. Plug the existing wye or tee with cement sock or T-cone plug. Damaged or broken wye/tee
connections and all tapped/saddle connections shall be removed and replaced with a new
section of pipe in kind.
2. For lined mains (CIPP, deformed and reformed, sliplining), remove the abandoned lateral at
the joint of the factory wye or tee, or at the closest joint of the lateral to the main. Install
cement sock or T-cone plug at wye or tee and at the downstream end of the abandoned
lateral. Fill the abandoned lateral with at least 2 feet of CDF at both ends of the abandoned
lateral.
B. The cleanout and riser shall be cut and plugged at least 3-feet below the finished grade. In non-
paved areas, the voids shall be filled with suitable material compacted to a relative compaction of
90% and concrete plugged. For paved areas, the remaining voids shall be filled with CDF, or
other flowable compaction fill and be concrete plugged, and the pavement shall be restored.
Where the cleanout is located in sidewalk, curb, or gutter, the surface shall be restored to match
existing.
C. Backfill and restore surface paving or landscape per current Water, Gas & Wastewater and
Public Works Standards.
PART III – SANITARY SEWER LATERAL SECTION 2737
CITY OF PALO ALTO SECTION 2737 PAGE 4
D. Abandonment of sewer laterals shall be scheduled and witnessed by CPA Utilities Inspector.
1.07 TESTING
A. The pipe shall be tested with low pressure air in accordance with ASTM F1417, Constant
Pressure Method. The pipe shall be tested with low pressure air at 3.5 psi for 5 minutes with NO
pressure loss. Wyes shall be plugged during test. Tests shall be made in the presence of the
Inspector.
B. If the pipe fails the air test, the Contractor shall locate the source(s) of the leak and repair the
defect(s) or relay the pipe, as necessary. The pipe shall then be retested until a satisfactory result
is obtained, at no expense to the City.
C. New laterals and/or reconnected laterals shall be video inspected per Section 2739 Cleaning and
Video Inspection of Sewer Pipe.
D. Despite any previous testing or CCTV inspection, any pipe defects developed before the end of
the 1-year guarantee period shall be expeditiously repaired by the Contractor at no expense to
the City.
END OF SECTION
CONCRETE MANHOLES SECTION 2738
CITY OF PALO ALTO SECTION 2738 Page 1
SECTION 2738
CONCRETE MANHOLES
1.01 SCOPE
This section covers the installation of new concrete sanitary sewer manholes and rehabilitation of
existing manholes. Manholes shall be as specified herein and installed at the locations shown on the
Drawings.
1.02 SUBMITTALS
The Contractor shall submit for approval by the Engineer the following:
A. Manufacturer's literature on the materials identified below. Literature shall include recommended
installation procedures.
B. Certification by the manufacturer that all precast sections furnished under this specification were
manufactured, sampled, tested, and inspected in accordance with the latest ASTM C 478 or
ASTM C 361.
C. Mix design of the concrete used for the pour-in-place manhole base.
1.03 MATERIALS
The concrete manhole materials are as follows:
A. Precast Sections: ASTM C 478. Forterra, Old Castle Precast, or approved equal. For greater
than 72-inch ID: ASTM C 361, Class D-25. Flush Bell design, centrifugally spun or wet cast.
Ameron, Concrete Pipe & Products, or approved equal.
B. Precast Manhole Base (upon Engineer’s approval only): ASTM C 478. Forterra, OldCastle
Precast, or approved equal.
C. Sealant: Ram-Nek, K.T. Snyder Company, Inc., or approved equal. Approved equal shall
meet or exceed all requirements of ASTM C990 Standard Specification for joints, concrete pipe,
manholes and precast box sections, using Preformed Flexible Joint Sealants. Meets
requirements of Federal Specifications SS-S210-A, "Sealing Compound Preformed Plastic For
Pipe Joints", Type 1, Rope Form
D. Frame and Cover: Rexus II 24” manhole frame and cover with spring bar lock as manufactured
by Pam Saint-Gobain or approved equal. When manhole lid is located within a traffic lane, the
hinge shall be located on the downstream side of the flow of traffic. See standard detail WWD-10
for casting imprint and additional details.
E. Concrete: CalTrans Standard Specification Section 90 Class II Concrete. CalTrans Standard
Specification.
F. Mortar: Section 51-1.02F, CalTrans Standard Specification. Mortar shall be non-shrink as
manufactured by Sika or approved equal.
CONCRETE MANHOLES SECTION 2738
CITY OF PALO ALTO SECTION 2738 Page 2
G. Water Stops: Molded plastic or rubber water stops by Mission Rubber, Newby Rubber, or
approved equal.
H. Drop Manholes: Drop manholes shall be installed whenever a pipe centerline entering a
manhole has an invert elevation 30 inches or more above the invert elevation of the outlet pipe in
the manhole base. See standard detail WWD-09.
1.04 MANHOLE INSTALLATION
Manhole bases shall be poured in a dry trench, using Class 2 concrete. Concrete will be sampled at
the Engineer’s discretion. Upon Engineer’s approval, precast manhole bases may be used on straight
runs and terminal manholes only. No field modifications of precast manhole bases shall be allowed.
During the pouring of the manhole base, precautions shall be taken to ensure that the sewer pipes
entering and leaving the manhole do not move from the installed alignment and grade. Plugs shall
be placed in open pipes to prevent concrete from entering the lines. Water stops shall be used on all
plastic pipes entering the manhole to prevent groundwater from leaking through the manhole wall.
Water stop shall be molded plastic or molded rubber.
The channels shall be shaped in flowing curves as indicated on the drawings to ensure good
hydraulic characteristics for the flow of wastewater. A smooth, clean, hand rubbed finish shall be
given to the surfaces of the manhole base and to any joint mortar work. Transitions between different
sizes of pipes shall be smooth and regular. Cracks, joints, holes, etc., shall be sealed with Sika or
approved equal non-shrink grout or sealing compounds to ensure watertight manholes.
When an existing VCP sewer main pipe is entering or leaving a newly constructed manhole,
Contractor shall replace in kind, a small section of new VCP pipe and connect to the existing VCP
pipe with a Anti-Radial (ARC) flexible coupling. Contractor shall remove the bell by making straight
cuts on both sides of new VCP pipe, refer to standard detail WWD-07B & 08B for specifications on
pipe length.
No more than twelve (12) vertical inches of grade rings shall be used to adjust the level of the
manhole frame (12 inches maximum between the top of the tapered manhole section and the bottom
of the manhole frame). Manholes shall be plumb.
Backfill shall be placed uniformly around the outside of the manhole so as to not create differential
forces and the possibility of dislodging the manhole sections.
1.05 NEW MANHOLE TESTING
The Contractor shall conduct a vacuum test (prior to manhole backfill) or an exfiltration test (after
manhole backfill) on each manhole constructedThe Contractor shall conduct an exfiltration test or
vacuum test on each manhole constructed. No testing is required on shallow manholes that are 24”
or less in depth. The test shall be conducted by the Contractor in the presence of the City Inspector
or Engineer.
Exfiltration tests shall consist of plugging incoming and outgoing sewer lines and filling the manhole
with water up to the rim. After initial absorption (15 minutes), if the water loss exceeds one inch in
depth in five minutes, the manhole shall have failed the test. Each manhole which fails the test shall
be carefully inspected to determine the problem and then resealed and retested until the water loss is
less than one inch in five minutes.
CONCRETE MANHOLES SECTION 2738
CITY OF PALO ALTO SECTION 2738 Page 3
Vacuum tests shall consist of drawing a vacuum on a sealed manhole and measuring the time for the
vacuum to drop to a predetermined level. Vacuum tests shall be conducted in accordance with ASTM
1244-11 “Standard Test Method for Concrete Sewer Manholes by the Negative Air Pressure
(Vacuum) Test Prior to Backfill” as follows.The actual test procedure shall be provided by the
manufacturer of the test equipment and approved by the Engineer. Each manhole which fails the test
shall be carefully inspected to determine the problem and then resealed and retested until the
manhole passes the vacuum test (3.5 psi for 5 minutes).
1. Contractor shall furnish all materials and equipment used for vacuum test.
2. Contractor shall furnish a vacuum test gauge that has a range of 0 to 30” Hg that can be
accurately read to 0.5 inch Hg and is in good working order; and a reliable source of vacuum
as needed to conduct the test.
3. Plug all manhole penetrations including lifting holes. Each plug must be installed at a location
beyond the manhole/pipe gasket (i.e., outside the manhole wall), and shall be braced to
prevent the plug or pipe from being drawn into the manhole.
4. Install the test head (e.g., a rubber ring “donut” type plug) inside the rim of the cast iron frame
at the top of the manhole and inflate it in accordance with the manufacturer's
recommendations.
5. Apply a vacuum to the test assembly and lower the internal pressure to approximately 10-
inch Hg vacuum. Permit the vacuum to stabilize for 1 minute, disconnect the vacuum source
and begin timing the test.
6. The time shall be measured for the vacuum to drop from 10-inches Hg to 9-inches Hg. The
manhole must maintain vacuum such that no greater than 1 inch Hg of vacuum is lost during
the specified test period per the following table:
Manhole Depth
(Feet)
Test Period Based On Manhole Size (seconds)
48 inch
Diameter
60 inch
Diameter
72 inch
diameter
Up to 8 20 26 33
10 25 33 41
12 30 39 49
14 35 46 57
16 40 52 67
18 45 59 73
20 50 65 81
>20 74 98 121
7. The manhole is acceptable if the time for the vacuum reading to drop from 10-inches Hg to 9-
inches Hg is greater than the test period. Manholes that fail the test shall be patched as
required and retested at no additional cost to the City.
8. Remove all temporary plugs and braces after each test.
CONCRETE MANHOLES SECTION 2738
CITY OF PALO ALTO SECTION 2738 Page 4
Exfiltration tests shall consist of plugging incoming and outgoing sewer lines and filling the manhole
with water up to the rim. After initial absorption (15 minutes), if the water loss exceeds one inch in
depth in five minutes, the manhole shall have failed the test. Each manhole which fails the test shall
be carefully inspected to determine the problem and then resealed and retested until the water loss is
less than one inch in five minutes.
1.06 EXISTING MANHOLE REHABILITATION
A. Existing Structures
Contractor shall find, uncover and recover (if required) missing structures as noted on the plans
or stated herein. Contractor shall utilize sonde’s, TV equipment, metal detectors, excavation
equipment, and other equipment needed to locate the sanitary sewer structure. Contractor shall
expose and document the location.
B. Seal Manhole
Sealing manhole structures consists of cleaning, filling voids, grouting joints, stopping leaks, and
coating the interior of the manhole with a sealer. The sealer shall penetrate the existing concrete
and form crystalline structures within the pores of the concrete that will seal the concrete.
1. Path holes and cracks using Perco Patch by Perco Industries or Patch ‘n Plug by Xypex.
2. Stopping leaks shall be done by chemical injection through interior wall of the manhole or
rapid-setting cement-based water-stop mortar to stop the infiltration. Chemical injection shall
be used per manufacturer’s recommendations for the existing site conditions.
3. The seal coating shall be an acrylic modified cementitious coating that is self-curing, suitable
for spray or brush application. The seal coating shall be Brush bond as manufactured by
Perco Industries or Xypex Concentrate as produced by Xypex.
C. Coat Manhole
Coat manholes with a monolithic ultra high-build epoxy lining to rebuild, eliminate infiltration,
provide corrosion protection, and repair voids. Procedures for surface preparation, cleaning,
application and testing are described herein. All application procedures shall follow the
manufacturer’s guidelines and meet the following minimum requirements:
1. Surface Preparation
a. Clean Surface – Clean the surface by removing any laitance, dust, unsound, looser, or
contaminated material, plaster, oil, paint, grease, corrosion deposits or bacteriological
growths. Chemical cleaning aids may be used with water blast equipment, however,
Engineer must approve detergents or degreasers proposed by the contractor and must
be suitable for the water temperature used in any pressure washer system employed.
Where breaking out mortar is not required, roughen the surface and remove any laitance
by mechanical means, low-pressure hot water blast (minimum 3500 psi pump pressure
at 4 gpm), or high-pressure cold water blast (>5000 psi pump pressure at 4 gpm) with or
without sand injection as is appropriate, abrasive (sand) blasting, acid etching and water
cleaning, or shotblasting to a sound profile surface. Follow surface cleaning procedures
with a soaking rinse of chlorinated water to destroy remaining biologics and neutralize
the surface. The chlorine solution shall be rinsed with fresh water after not less than
CONCRETE MANHOLES SECTION 2738
CITY OF PALO ALTO SECTION 2738 Page 5
fifteen minutes dwell time. Test the wet surface pH with universal pH indicator paper with
a range of pH 0-10, or other suitable test instrument. Acceptable surface pH for epoxy
grouting repairs and lining shall be not less than 6 or more than 9.
b. Stop Leaks/Fill Voids – Seal leaks with epoxy grout on the surface that is coated. Fill any
voids with epoxy patching material or grout according to the manufacturer’s
recommendations for flowing or weeping water conditions, rapid setting cementitious
“plug” materials may be used instead of epoxy grouts. Exterior injection of a gel type
chemical grout shall be used, if necessary.
2. Apply Coating: After the surface is properly prepared to apply the coating, apply the epoxy
liner by trowel or spray. The epoxy liner thickness shall be a minimum of 125 mils over the
entire surface. Manholes shall be coated from the frame and cover to the pipe in the channel.
If the pipe does not go through the manhole, the coating shall extend to at least the
springline of the pipe. The applicator shall be certified by the coating manufacturer to apply
the coating.
The inspector shall verify that the surface preparation, coating application, and final product
meet the requirements specified herein and the manufacturer’s requirements. A
manufacturer’s representative shall also be available for consultation and site visits, if
required by the City.
3. Test Requirement for Coated Manhole: Testing of coated manholes shall follow epoxy
manufacturer’s recommended testing method and procedures.
D. Drill Holes
Drill a hole or enlarge existing hole to 1.25” in diameter through the manhole cover.
E. Modify Channel
Chip and/or rework channels within the manhole to improve the flow through the manhole and to
the new pipes and to allow better access for video equipment. Channels shall be chipped to
sound material and approximate contour. Chipped areas shall be smoothened out using a
cementitious patching material.
F. Frame and Cover
Replace existing frame and cover and reset with a concrete ring as described in the Standard
Details.
G. Realign Frame and Cover
Realign existing frame and cover and reset with a concrete ring as described in the Standard
Details.
H. Raise Manhole
Add one 48” barrel section up to 3 feet and/or 24” rings up to the 12 inches to raise the
manhole’s frame and cover to grade, if not noted on the plans or described herein. Reset frame
and cover with a concrete ring as described in the Standard Details.
CONCRETE MANHOLES SECTION 2738
CITY OF PALO ALTO SECTION 2738 Page 6
CONCRETE MANHOLES SECTION 2738
CITY OF PALO ALTO SECTION 2738 Page 7
1.07 CONNECTIONS TO EXISTING MANHOLES
The preferred method of sewer lateral connection to existing manhole wall or base is core drilling.
Hammering of holes is acceptable but limited to a maximum size of sixty-pound jackhammers. The
use of precision “chipping” equipment will only be acceptable with prior approval from the on-site field
Inspector.
A water stop shall be used on all plastic pipe entering manholes. All pipe penetrations shall be
sealed with a non-shrink grout. Channel bottoms shall be reworked to provide a smooth flowing
transition from the new pipes to the outlet pipe. Subject to manhole testing as described in Section
1.045.
1.08 EXISTING MANHOLE TESTING
The Contractor shall conduct a vacuum test on each rehabilitated manhole and/or each manhole in
which a new main is connected as part of a capital improvement project. Each test shall be
conducted as described in Section 1.04 05 of this Specification. The test shall be conducted by the
Contractor in the presence of the City Inspector or Engineer.
Each rehabilitated manhole which fails the test shall be carefully inspected to determine the problem,
resealed as needed, and retested until the manhole passes the vacuum test. For existing manholes
in which a new main is connected, Contractor shall test the manhole once the penetration has been
sealed, and report back to the City Inspector or Engineer the test results. If the existing manhole fails
the test, the City may direct the Contractor to rehabilitate and retest the manhole as part of additional
work.
1.09 MANHOLE ABANDONMENT
Where a manhole is to be abandoned within the street, the Contractor shall break the bottom of the
manhole and remove the frame, cover, taper and barrel sections. The manhole shall be filled with 1-
1/2 sack slurry. Where a manhole is to be abandoned within native soil, the Contractor shall break the
bottom of the manhole and remove the frame, cover, taper and barrel sections and fill the manhole
with ¾” gravel up to 3-feet below grade and fill the upper 3-feet with native soil compacted to 95% or
better. Pipe connections to the manhole are to be plugged.
END OF SECTION
CLEANING AND VIDEO INSPECTION OF SEWER PIPE SECTION 2739
CITY OF PALO ALTO SECTION 2739 PAGE 1
SECTION 2739
CLEANING AND VIDEO INSPECTION OF SEWER PIPE
1.01 SCOPE
This section covers the cleaning and video inspection of sewer pipelines and video processing
software and equipment. The word "clean" in this section is defined as the removal of all
accumulations including sludge, dirt, sand, rocks, grease, roots, and other solid or semisolid material
in the pipe or manhole and on the pipe or manhole inside wall, down to the parent material.
1.02 SUBMITTALS
A. Contractor shall submit NASSCO PACP and/or LACP certificates, as applicable, for the video
operator coding the video.
B. The Contractor shall submit the first 1,000 LF of video inspected by each operator for Engineer’s
review and acceptance, before continuing the work, to ensure the quality and adequacy of the
output.
C. The Contractor shall submit colored-video, audio, and NASSCO condition assessment report for
completed work on USB flash drive, hard drive, or provided through a Cloud platform with the
monthly progress payment requests. The video must be in 19x20 MP4 file format. Work will
not be considered accepted until these items have been received and approved by the Engineer.
1.03 CAMERA OPERATOR PRE-QUALIFICATIONS
Camera Operator Experience: Each camera operator shall have a minimum of 1 year of experience
in projects televising sanitary sewer mains and laterals and commenting on observed defects. Each
camera technician shall be NASSCO PACP and/or LACP certified.
1.04 MATERIALS
A. Cleaning Equipment
1. Hydro-Jetting
a. High-Velocity or Hydro-cleaning Equipment shall be truck mounted for ease of
operation. The equipment shall have a minimum of six hundred (600) feet of high-
pressure hose with a selection of two or more high velocity nozzles. Nozzles shall
be capable of producing a scouring action from 15 degrees to 45 degrees in all
designated line sizes. The equipment shall carry its own water tank capable of
holding corrosive or caustic cleaning or sanitizing chemicals, auxiliary engines and
pumps, and hydraulically driven hose reel. All controls shall be located so that the
equipment can be operated above ground. Equipment shall include a high-velocity
gun for washing and scouring manhole walls and floor. The gun shall be capable of
producing flows from a fine spray to a solid stream.
2. Mechanical Cleaning
a. Rodding Machines – Root cutters and porcupines shall be attached to the winches
and be used as necessary to remove roots, grease, and other debris. The
attachments shall be suitable for the type of pipe that is being cleaned. A power
rodding machine shall be either a sectional or continuous-rod type capable of
CLEANING AND VIDEO INSPECTION OF SEWER PIPE SECTION 2739
CITY OF PALO ALTO SECTION 2739 PAGE 2
holding a minimum of 750 feet (230 m) of rod. The machine shall be fully enclosed
and have an automatic safety clutch or relief valve.
b. Bucket Machines – Bucket machines shall be used in pairs with sufficient power to
perform the work in an efficient manner. Machines shall be belt operated or have an
overload shutoff device. Machines with a direct drive that could cause damage to the
pipe will not be allowed. Bucket machines shall not be used on any host or
rehabilitated pipeline that is lined with a plastic pipe or material.
c. Chemicals – Chemicals made for sanitary sewer use and acceptable to the City’s
Water Quality Control Plant may be used to remove grease and kill roots.
B. Video Inspection
1. Push Camera – The push camera shall have a sonde transmitter. The equipment will be
used in a wastewater pipes with an internal diameter of less than six (6) inches. Small
diameter push camera shall be able to access building cleanouts that are two (2) inches in
diameter.
Both cameras must be able to be traced throughout the entirety of the inspection. The
equipment must have the ability to be located above grade using the sonde locator.
The footage counter for each push-camera must be accurate to 0.5 feet per 100 feet over the
length of the particular section of pipeline being inspected. At the City’s request, the footage
counter shall be replaced if the footage counter produces inspection footage that is outside
the acceptable accuracy.
The equipment lighting must illuminate the entire pipe, but shall not oversaturate the footage
of pipe.
2. Mainline Camera and Lateral Launch – CCTV system equipment shall include television
cameras, a television monitor, cables, power sources, and other equipment. The mainline
camera equipment shall include a multi-angle television camera capable of spanning 360
degrees circumference and 270-degrees on the horizontal axis to televise sewer lines 6-
inches in diameter or larger; the purpose of the rotating head camera is to view all service
connections, upstream and downstream manhole structures, and to locate all defects, as
well as questionable problem areas; focal distance shall be adjustable through a range of
one (1) inch to infinity. The television camera shall be color format and specifically designed
and constructed for operation in connection with sewer inspection and for operation in
sewers less than 100% humidity conditions. Lighting and camera quality shall produce a
clear, in-focus picture of the entire periphery of the pipe for a minimum distance of six feet.
Other required equipment includes television monitor, cables, power sources, lights, and
other equipment necessary to do the work. The remote-reaching footage counter shall be
accurate to 0.5 feet per 100 feet over the length of the particular section of pipeline being
inspected. The camera equipment shall have a sonde transmitter and have the ability to be
located above grade.
3. Video Processing System – The video processing system shall be the software system
Granite XP, as used by the City, or a compatible database format system that can use the
existing generic connector to convert to a Granite XP format. Video format shall be .MP4 and
files shall be exported in PACP database format. Contractor shall provide a composite PACP
video report that includes comment/defect code and footage with each associated still
picture. Video Codeset – Video codeset shall be PACP 4.2, 4.4, or 6.0 formatted data.
CLEANING AND VIDEO INSPECTION OF SEWER PIPE SECTION 2739
CITY OF PALO ALTO SECTION 2739 PAGE 3
1.05 VIDEO INSPECTION AND CLEANING
Pre-Construction:
For all water, gas, and wastewater CIP projects, the contractor shall perform pre-construction
cleaning and video inspection of existing wastewater pipelines to identify active sewer laterals. Prior
to performing sewer main pipe-bursting operation, the Wastewater CIP contractor shall also perform
pre-construction cleaning and video inspection of existing sewer mains and laterals to verify no cross-
bore is present and to identify/evaluate sags in the existing sewer main and discuss with the
Engineer to determine whether spot repair is required. For existing wastewater pipelines to be
replaced by pipe bursting, the Contractor shall video inspect wastewater pipelines prior to
commencing pipe bursting to verify if a cross-bore or sags are present. Refer to Section 2739, 1.05 B
Obstructions and Cleaning. The cost for pre-construction cleaning and video-inspecting work shall
be included in one or more bid items.
Post-Construction:
For water and gas utilities installed by drilling or other trenchless installation method, the contractor
shall perform post-installation video inspection of sewer mains and laterals to verify that there is no
cross-bore present. For wastewater CIP projects, the contractor shall perform new wastewater
pipelines, post-installation cleaning and video-inspection of the newly installed sewer mainsshall be
performed. New wastewater pipelines are the pipelines installed as a part of the capital improvement
project. The cost for post-construction cleaning and video-inspecting work shall be included in one or
more bid items.
A. Video Inspection
1. Wastewater Main Video Inspection – Depth of flow shall not exceed twenty percent (20%) of
the inside pipe diameter as measured in the manhole when performing video inspection. In
the event the depth of flow of the reach being televised exceeds twenty percent (20%) of the
inside pipe diameter, the Contractor shall monitor the sanitary pipes to be inspected to
determine video inspection schedule or to provide the necessary flow control or reschedule
the inspection for a time when such flow is reduced to permit proceeding with the work. If
nighttime work is necessary, the Contractor shall obtain a "Noise Exception Permit" from the
CPA Planning & Development Services (285 Hamilton Avenue, Palo Alto, CA 94301).
The video shall start outside the manhole and end inside the end structure capturing video of
both structures prior to setting the start footage, and after the footage is stopped. The
camera shall be moved through the pipeline in either direction at a uniform rate, stopping
when necessary to ensure proper documentation of the sewer's condition. In no case shall
the television camera be pulled or propelled at a speed greater than thirty (30) feet per
minute. The camera height shall be adjusted such that the camera lens is always centered
in the pipe being inspected. The equipment shall have an accurate footage counter, which
shall display on the monitor the exact distance of the camera from the centerline of the
starting manhole. Unless otherwise approved by the Engineer, footage measurements shall
begin at the centerline of the upstream manhole.
The video inspection shall follow PACP and/or LACP formatting that includes the
documentation that describes the inspection location and other parameters associated with
the inspection. Data of significance includes, but is not limited to, the locations of service
connections, types of upstream and downstream manhole structures, and any pipe defects.
Footage shall be imbedded in the video (Granite XP) or burned on the video in addition to
CLEANING AND VIDEO INSPECTION OF SEWER PIPE SECTION 2739
CITY OF PALO ALTO SECTION 2739 PAGE 4
other footage indicators or recorded events. If the recordings are of such poor quality that
the Engineer is unable to evaluate the condition of the sewer, locate sewer service
connections, or verify cleaning, the Contractor shall re-televise the sanitary sewer and
provide a new recording of good quality at no cost to the City. No payment will be made for
recordings that do not meet the requirements of these specifications.
2. Wastewater Lateral Video Inspection – Where inspection cannot be completed using a
lateral launcher, the Contractor shall use a push camera to complete the inspection. The
push camera is inserted at a cleanout and is moved downstream toward the wastewater
main.
If branched laterals are encountered, the Contractor shall attempt to locate cleanout of the
branched lateral to access for inspection.
If a cleanout is not available, the Contractor may request City-approval to perform push
camera inspections through a roof vent. The contractor must provide the appropriate
equipment to perform push camera inspection from the roof vent. This includes ladders,
harnesses, and any other equipment required to safely perform the push camera inspection.
The Contractor is responsible for any damages occurred during inspection through a roof
vent and the safety of their employees. The Contractor shall not enter the property of the
occupant nor access the roof vent without the presence of the City Inspector.
B. Obstructions and Cleaning
Where an obstruction such as roots, debris, deposits, fat, oil or grease is encountered and
prevent the camera inspection equipment from capturing complete footage of the wastewater
pipe, the Contractor shall perform high-velocity hydraulic cleaning to attempt to remove the
obstruction. The Contractor shall attempt a minimum of 2 passes with the hydraulic nozzle unless
otherwise approved by the Engineer.
For wastewater mains that cannot be cleaned by hydraulic cleaning from one manhole, the
equipment shall be moved and set up at the other manhole and cleaning shall be re-attempted to
remove the debris. If successful removal of the debris cannot be performed or the equipment
fails to traverse the entire pipeline section, it shall be assumed that a major blockage exists.
Where there is a major blockage preventing its removal, the Contractor shall notify the Engineer
and remove the obstruction by a method approved by the City.
For wastewater laterals, obstructions shall be attempted to be removed by hydraulic cleaning
shall only be performed in the downstream direction toward the wastewater main. If the
obstruction cannot be removed by hydraulic cleaning, the Contractor shall notify and provide a
still-image of the obstruction to the Engineer. The obstruction shall be removed by excavation,
repair, or other means approved by the Engineer.
If a sag prevents the complete inspection of a wastewater pipe, the Contractor shall inspect from
the downstream point of connection and from the upstream access point to verify that a sag is
present. Where the sag is present, the Contractor shall be required to remove the section of pipe
that has a sag and replace it to the nearest joint. If the method of pipeline replacement is pipe
bursting and total number of sags along a wastewater main, between two manholes, are
encountered exceed three (3), the Contractor shall replace the wastewater main by open trench
excavation.
Where roots or a root ball are encountered that cannot be removed by hydraulic cleaning, the
Contractor shall excavate at the location of the roots or root ball and perform a point repair of the
CLEANING AND VIDEO INSPECTION OF SEWER PIPE SECTION 2739
CITY OF PALO ALTO SECTION 2739 PAGE 5
pipeline if pipe bursting or lining shall be performed. Roots shall not be a reason for reverse set-
up. Special attention should be used during the cleaning operation to ensure complete removal
of roots from joints of pipelines that are 33-inches or smaller. For pipes 36-inches in diameter or
larger, the Contractor shall remove 90 – 95% of roots from pipe joints.
Where a protruding lateral prohibits the Contractor from performing a lateral launch, the
Contractor shall notify the City Inspector and provide a still-image of the protruding lateral to
Utilities Engineering. The still-image will be forwarded to Utilities Operations and its removal will
be scheduled. The Contractor will be notified when the protruding lateral is removed.
If a suspected cross bore is encountered, the Contractor shall notify the Engineer and provide a
still-image of the cross bore encountered to the City. Utilities Operations will be notified to
schedule the necessary repairs and the Contractor shall be notified of when the repairs are
completed.
Mechanical cleaning is not permitted on plastic pipes and will only be permitted after the pipe has
been cleared of cross bore(s).
Debris removed from the pipeline(s) as a result of cleaning shall be removed from the
downstream manhole receiving flow from the pipeline(s) cleaned. Prior to analysis and disposal,
debris shall be captured using a filtering device. Such materials collected at the downstream
manhole shall become the responsibility of the Contractor, removed from the site by the
Contractor in a closed container, and disposed of in accordance with Federal, State, and local
laws and regulations at an appropriately classed landfill. The debris collected by the Contractor
shall not be dumped into streets, ditches, catch basins, or storm sewers. Flushing of the material
from manhole reach to manhole reach is prohibited.
Acceptance of the sewer line cleaning shall be made upon the successful completion of the video
inspection and shall be to the satisfaction of the Engineer. If video inspection shows the cleaning
to be unsatisfactory, the Contractor shall be required to re-clean and re-inspect the sewer main
at no additional cost to the City.
END OF SECTION
SURVEY DATA COLLECTION SECTION 2740
CITY OF PALO ALTO Section 2740 PAGE 1
SECTION 2740
SURVEY DATA COLLECTION
1.01 BASIS OF SURVEY CONTROL
The City of Palo Alto has established a GPS Control Network and survey control monuments
throughout the City to be used as the official survey control benchmarks. All surveying and
engineering related work shall use these monuments in order for the projects to be incorporated into
the City's GIS mapping. To satisfy the City of Palo Alto horizontal coordinate & vertical datums, the
surveyor must tie the requested work to the City GPS control monuments prepared by Bestor
Engineers in 1994 and submit your northings and eastings in the City’s coordinate system. The City
will not accept deliverables in other coordinates systems and/or own local ("project") coordinate
systems.
The coordinates shown on the record of survey are based on the North American Datum of 1983
[NAD 83(1992 epoch)] in the California State Plane Coordinate System, (zone 3) in units of survey
feet. Vertical elevations are based upon the NGVD 29 as per the USC&GS adjustment of 1967.
Additional information concerning elevations and secondary vertical control benchmarks to be used
for vertical control only is on file and available at the City of Palo Alto Public Works engineering
surveying office. The data provided by Public Works is intended to be used as a reference.
Horizontal and vertical control reference point data is available upon request. Copies of full size of
the Record of Survey and Survey Control Monument maps prepared by Bestor Engineers, Inc. dated
February 1994 are available at the Utilities Engineering Office.
Per submittal requirement prior to construction commencement, the contractor shall submit
coordinate text files (PNEZD) of all survey control monuments needed to perform the survey work for
the City to validate its accuracy and delivery in the City’s coordinate system.
A California Licensed Land Surveyor is responsible to setup all control points needed to perform the
survey work. The accuracy for all survey data shall be +/- 0.5 in; with an exception of gas meter risers
on private properties to be +/- 0.5 ft. For CIP pipeline replacement projects, all survey data collected
shall be certified by a California Licensed Land Surveyor.
Per submittal requirement prior to construction commencement, the contractor shall submit
coordinate text files (PNEZD) of all necessary survey control monuments for the City to validate its
accuracy and delivery in the City’s coordinate system. Use CPAU WGW Engineering’s "feature
codes" for naming convention and refer to the feature capture-positions in the ‘Feature Codes and
Feature Capture-Positions’ table at the end of this section.
In addition, the Contractor shall submit the GPS data set collected for the installation work during the
first week of construction for the City to validate its accuracy. The completeness and accuracy of
GPS survey data shall be verified by the City before the issuance of each payment to the contractor.
For CIP projects, the City of Palo Alto may require the Contractor, at Contractor’s own expense, to
reopen or uncover GPS surveyed infrastructure/objects and perform new survey if the accuracy of
the originally submitted data is not in compliance with these specifications or the data is not collected
in open-hole. The Contractor will be required to perform surface restoration, at the Contractor’s own
expense, following the additional survey.
When applicable, survey data shall be collected within the entire width of the street and on private
properties to include all features identified in Table 2. The extents of the survey area shall cover the
SURVEY DATA COLLECTION SECTION 2740
CITY OF PALO ALTO Section 2740 PAGE 2
full intersections to curb returns. The consultant/contractor shall obtain approval from business/home
owners or occupants to access private properties for collecting required survey data. No additional
compensation will be made for delays due to private property accessing issues. The
Consultant/contractor shall provide necessary traffic control to meet the CPA Transportation
Department’s standards. No additional compensation will be made for traffic control on major streets.
1.02 SURVEY DATA COLLECTION
A. Deliverables
1. Prior to construction commencement - Northing and easting coordinate text files (PNEZD) of
all control survey points needed to perform the survey work in .csv format, including feature
code of each point in the spreadsheet.
2. Northing and easting coordinate text files (PNEZD) of survey points for all new utility features
installed during the first week of construction in .csv format, including feature code and
description (if applicable - in same column), of each point in the spreadsheet.
3. Survey data in .csv format with benchmarks, surveyed points, and feature codes shall be
submitted monthly or with each partial progress payment request. Refer to in accordance
with Section 800 Additional Provisions for additional requirements for Utilities CIP
ProjectsContractors. Payment will be made on the percentage of total project completed,
submitted, and accepted.
B. Data to be collected (See table 2 for feature capture-position)
1. Sanitary Sewer Rehabilitation Projects
a. Collect horizontal and vertical data for:
i. Sanitary sewer manholes.
1. Lid (center)
2. Depth
3. Invert elevations for each pipe
4. In/out directions for each pipe relative to magnetic North.
ii. Lateral connections to mains (at the top of the pipes, to be collected in open holes
during construction [i.e. prior to backfilling]).
iii. Changes in pipe alignment (at the top of the pipes, to be collected in open holes
during construction [i.e. prior to backfilling]).
b. Collect horizontal data for:
i. Lateral cleanouts
2. Water Main Replacement Projects
a. Collect horizontal and vertical data for:
i. Water valves, including all main line valves, service valves, fire hydrant valves, and
blow off valves.
ii. Service connections to mains (at the top of the pipes, to be collected in open holes
during construction [i.e. prior to backfilling]).
iii. Tapping tees for all water connections (at the top of the tee, to be collected in open
holes during construction [i.e. prior to backfilling]).
SURVEY DATA COLLECTION SECTION 2740
CITY OF PALO ALTO Section 2740 PAGE 3
iv. Main and service reconnection points (at the top of the fitting or pipe, to be collected
in open holes during construction [i.e. prior to backfilling]).
v. Changes in pipe alignment (at the top of the pipes, to be collected in open holes
during construction [i.e. prior to backfilling]).
vi. Fittings, including couplings, reducers, elbows, sleeves, caps and line stops (at the
top of the fittings, to be collected in open holes during construction [i.e. prior to
backfilling]).
vii. Anode boxes (typically installed near fire hydrants).
b. Collect horizontal data for:
i. Fire hydrants
ii. Air release valves
iii. Water meters
iv. Sewer manholes (for data validation purpose)
3. Gas Main Replacement Projects
a. Collect horizontal and vertical data for:
i. Gas valves, including all main line, service, and excess flow valves.
ii. Service connections to mains (at the top of the pipes, to be collected in open holes
during construction [i.e. prior to backfilling]).
iii. Tapping tees for all gas connections (at the top of the tee, to be collect in open
holes during construction [i.e. prior to backfilling]).
iv. Changes in pipe alignment (at the top of the pipes, to be collected in open holes
during construction [i.e. prior to backfilling]).
v. Fittings, including couplings, transition fittings, reducers, elbows, end caps, etc., to
be collected in open holes during construction [i.e. prior to backfilling]).
b. Collect horizontal data for:
i. Anode boxes
ii. Gas meters
iii. Gas meter curbs
iv. Gas risers (end of riser or at ground penetration)
v. Sewer manholes (for data validation purpose)
4. Miscellaneous Development Service Projects and Survey Contracts
a. Collect horizontal and vertical data for:
i. Sanitary sewer manholes.
a. Lid (center)
b. Depth
c. Invert elevations for each pipe
d. In/out directions for each pipe relative to magnetic North.
ii. Storm drain manholes, catch basins, culverts and inlets.
a. Lid (center); catch basin, culvert, inlet (top center at inlet)
b. Depth
c. Invert elevations for each pipe
d. In/out directions for each pipe relative to magnetic North.
iii. All gas and water valves.
iv. Street Surface along the crown of the pavement (i.e. along the approximate
centerline of the street width) at grade breaks and every 50’ maximum.
SURVEY DATA COLLECTION SECTION 2740
CITY OF PALO ALTO Section 2740 PAGE 4
b. Collect horizontal data for: (collect data at center of manholes, lids, and boxes unless
otherwise noted.)
i. Electrical/Fiber Optic/Telephone manholes and boxes
ii. Fire hydrants
iii. Anode boxes
iv. Air release valves
v. Water and gas meters
vi. Lateral cleanouts
vii. Main cleanouts
viii. Lampholes
ix. Flush inlets
x. Gas risers (at ground penetration)
xi. Front and back of sidewalk, face of curb, lip of gutter and edge of pavement on both
sides. For linear alignment collect data at both ends of the block. For non-linear
alignment collect data at every turning point.
xii. Monuments
See Table 2 for each feature description, feature code and feature capture-position for the survey
data that is being requested.
Table 2: Feature Codes and Feature Capture-Positions
Feature Description Feature Code Feature Capture-Position
SURVEY REFERENCE POINT
Benchmark BM
Back Site Point BSPT
ROAD FEATURES
Back of Curb BOC Back of curb
Back of Rolling Curb BORC Back of rolling curb
Bridge, Edge BREDGE Edges of bridge outline
Back of Sidewalk BSW End pts. on straight alignment & every turning pt.
Back of Valley Gutter BVG At flow line
Crown of Street CROWN End pts. on straight alignment & every turning pt.
Ditch DITCH At flow line
Driveway DWY Edge of driveway both sides
Edge of Pavement EOP Both ends of the block and every turning pt.
Fence FENCE End pts. on straight alignment & every turning pt.
Flow Line FL End pts. on straight alignment & every turning pt.
Face of curb FOC End pts. on straight alignment & every turning pt.
Lip of Gutter LOG End pts. on straight alignment & every turning pt.
Loop Detector LOOPDE As needed
Street Monument MONSTR Center of lid/cover
Swale at Flow Line SWALE As needed
Traffic Speed Control TRSPCN As needed
Traffic Speed Donut TRSPDON As needed
Street Turn Around TURNARO As needed
Guard Rail GUARDR As needed
Parking Lot PARKING Edges of parking lot
Speed Bumps SPEEDB As needed
BUILDING
Building BLDG Building corners
WATER
SURVEY DATA COLLECTION SECTION 2740
CITY OF PALO ALTO Section 2740 PAGE 5
Air Relief Valve WTARV Center of valve
Detector Check Valve WTDCV Center of valve
Fire Hydrant WTFH Center of hydrant
Water Main WMAIN End pts. on straight alignment & every turning pt.
Water Main Tapping Tee WTTEE Service connection point to main
Water Service WTSVC End pts. on straight alignment & every turning pt.
Water Service Saddle WTSDL Center top of main at service connection
Water Valve - Main WTVMAIN Center of lid/cover and stem
Water Valve - Service WTVSVC Center of lid/cover and stem
Water Valve - Fire Hydrant WTVFH Center of lid/cover and stem
Water Valve - Blow-Off WTVBO Center of lid/cover and stem
Water Meter WTM Center of meter
Miscellaneous Fittings:
Coupling WTCPL Center of fitting
Horizontal Elbow 11 WTELB11 Center of fitting ( point of turn) 11 degrees
Horizontal Elbow 22 WTELB22 Center of fitting (point of turn) 22 degrees
Horizontal Elbow 45 WTELB45 Center of fitting (point of turn) 45 degrees
Horizontal Elbow 90 WTELB90 Center of fitting (point of turn) 90 degrees
Vertical Elbow 11 WTELBV11 Center of fitting ( point of turn) 11 degrees
Vertical Elbow 22 WTELBV22 Center of fitting (point of turn) 22 degrees
Vertical Elbow 45 WTELBV45 Center of fitting (point of turn) 45 degrees
Vertical Elbow 90 WTELBV90 Center of fitting (point of turn) 90 degrees
Reducer WTRDC Center of fitting
Sleeve WTSLV Center of fitting
Cap WTCAP Center of fitting
Line Stop WTLS Center of fitting
Anode Box WTANOBOX Center of lid/cover
GAS
Existing Anode Box ANOBOX Center of lid/cover
Gas Meter GM Center of meter
Gas Meter Curb GMCURB Center of meter
Gas Riser GRISER Front of riser perpendicular to main
Gas Main GMAIN End pts. on straight alignment & every turning pt.
Gas Main Tapping Tee GTEE Service connection point to main
Gas Service GSVC End pts. on straight alignment & every turning pt.
Gas Valve - Main GVMAIN Center of lid/cover and stem
Gas Valve - Service GVSVC Center of lid/cover and stem
Miscellaneous Fittings:
Coupling GCPL Center of fitting
Horizontal Elbow GELB Center of fitting ( point of turn)
Vertical Elbow GELBV Center of fitting ( point of turn)
Reducer GRDC Center of fitting
Sleeve GSLV Center of fitting
Cap GCAP Center of fitting
Line Stop GLS Center of fitting
WASTEWATER
Wastewater Main WWMAIN End pts. on straight alignment & every turning pt.
Wastewater Main Tapping Tee WWTEE Lateral connection point to main
Wastewater Lateral WWLAT End pts. on straight alignment & every turning pt.
Wastewater Clean Out WWCO Center of lid/cover
Wastewater Flushing Inlet WWFI Center of lid/cover
SURVEY DATA COLLECTION SECTION 2740
CITY OF PALO ALTO Section 2740 PAGE 6
Wastewater Lamp Hole WWLH Center of lid/cover
Wastewater Manhole WWMH Center of lid/cover, depth, invert elevations and
in/out directions relative to magnetic north
ELECTRIC
Electrical Vault 1,2,3,4 Lids ELVLT Center of vault
Electrical Manhole EMH Center of lid/cover
Fiber Optic Manhole FMH Center of lid/cover
Fiber Optic Vault FVAULT Center of vault
Telephone MH TELMH Center of lid/cover
Telephone Vault TELVAULT Center of vault
STORM DRAIN
Box Culvert BOXCLV Center line
Catch Basin CB Center of grate, depth, invert elevations and
in/out directions relative to magnetic north
SD Headwall SDHW As needed
SD Inlet SDIN As needed
SD Manhole SDMH Center of lid/cover, depth, invert elevations and
in/out directions relative to magnetic north
1.03 CONSTRUCTION STAKING FOR CIP PROJECTS
The Contractor shall be responsible for construction staking of open trench construction and marking
proposed pipeline alignment per project plans for CIP projects. All survey work for construction
staking shall be performed by a California Licensed Land Surveyor. The surveyor is responsible to
setup all control points needed to perform the survey work.
END OF SECTION
LEGACY CROSS BORE INSPECTION GUIDELINES SECTION 2741
CITY OF PALO ALTO: Legacy Cross Bore Inspection Guidelines Section 2741 PAGE 1
SECTION 2741
LEGACY CROSS BORE INSPECTION GUIDELINES
PART 1 – GENERAL
1.01 DESCRIPTION
This section covers the video inspection of sewer laterals installed by trenchless methods to locate
cross bore and submission of Lateral Assessment and Certification Program (LACP) as per National
Association of Sewer Service Companies (NASSCO) Standards.
LACP reports should only be submitted for the City-owned portion of the laterals (lower sewer lateral).
Only crossbore-inspection videos should be submitted for the private sewer laterals (upper sewer
lateral) including laterals in private easements or non-City-owned laterals.
“Cross bore” is an unintended conflict between natural gas service pipelines and sanitary sewer
laterals.
1.02 RELATED WORK
Section 01500 Traffic Control
Section 02200 Excavation, Backfill, and Restoration
PART 2 -- MATERIALS
2.01 EQUIPMENT
A. CAMERA
The equipment shall include full-color video cameras, video monitor cable, power sources, and all
necessary equipment to perform a complete CCTV video inspection of sanitary sewer laterals. The
camera equipment shall meet the California Division of Occupational Safety and Health for Electrical
Sewer Inspection Camera Sections 2340.11 (Water Safety) and 2540.2 (Fire Safety) for performing
inspections within wastewater facilities.
1. LATERAL LAUNCHER
The lateral launcher shall have a sonde transmitter. The equipment shall perform remote-
controlled inspections in most sewer laterals with wastewater main pipelines having an
internal diameter equal to six (6) inches to no larger than forty-two (42) inches. The
equipment should be capable of working within large diameter pipes which often require
special procedures for flow control, lighting, and camera travel. Lateral launch cameras shall
have a steering arm to provide navigation through wyes and tees in the sewer lateral.
2. PUSH CAMERA
The push camera shall have a sonde transmitter. The equipment will be used in a wastewater
pipeline or sewer lateral with an internal diameter of less than six (6) inches. A small diameter
push camera shall have the ability to enter through building cleanouts that are two (2) inches
in diameter.
Both cameras used must be able to be traced throughout the entirety of the inspection. The
equipment must have the ability to be physically located from above grade through a sonde
locator.
LEGACY CROSS BORE INSPECTION GUIDELINES SECTION 2741
CITY OF PALO ALTO: Legacy Cross Bore Inspection Guidelines Section 2741 PAGE 2
The footage counter for both cameras must be calibrated during video inspection and must
be accurate to 0.5 feet per 100 feet. At the City’s request, the Contractor may be required to
replace the footage counter to capture accurate counter readings. The travel speed should
be a uniform rate of no more than thirty (30) feet per minute. The equipment should be slower
when recording features and defects of the City-owned sewer lateral (lower sewer lateral).
The lighting of the equipment shall fully illuminate the entire pipe but shall not oversaturate
the footage of pipes. The operator shall ensure that the camera and video show a correct
reflection of the true colors within the pipe and on the video display. The camera lens shall
be kept clear of condensation and debris and shall be able to operate in one hundred percent
(100%) humidity.
B. WATER JETTER
1. The Contractor shall perform water jetting services if a blockage prevents complete
inspection of the pipe. Water jetting will be initiated via the cleanout.
2. The equipment should not have a saw or a cutting head attached.
3. The equipment must have a minimum capability of providing a 2,000 psi and a maximum of
4000 psi (pounds per square inch) of water pressure and a maximum output of 18 gallons
per minute.
4. The equipment must have a minimum of 1,500-gallon water tank.
C. HYDRO – EXCAVATION
1. The equipment must have a minimum capability of providing a 2,500 psi force of water with
rotating digging tips.
2. The equipment must have a minimum of 1,500-gallon water tank.
D. CLEANOUT PLUG WRENCH
1. The Contractor shall utilize a cleanout plug wrench to remove cleanout lids and avoid damage
to cleanout plugs. The Contractor shall be responsible for repairing any damages caused by
their forces to cleanouts. The Contractor is required to bring extra cleanout covers/plugs of
varying sizes to replace damaged cleanout covers/plugs during the inspection.
PART 3 – QUALIFICATIONS, TESTING, AND INSPECTION
3.01 OPERATOR QUALIFICATIONS
The Contractor shall have participated in a minimum of 1,000 sewer lateral inspections associated
with a gas cross bore inspection program.
The lower sewer lateral shall be assessed by a certified NASSCO Lateral Assessment and
Certification Program (LACP) trained operator or technician.
3.02 INSPECTION
A. HEALTH
1. The Contractor performing the push-camera inspection shall wear proper PPE such as
LEGACY CROSS BORE INSPECTION GUIDELINES SECTION 2741
CITY OF PALO ALTO: Legacy Cross Bore Inspection Guidelines Section 2741 PAGE 3
disposable gloves and safety glasses.
B. LATERAL LAUNCHER
2. The lateral launcher must have the capability of traversing a minimum of 150 feet.
3. The video inspection must begin from the wastewater main pipeline to the foundation of the
structure or extend three (3) feet beyond the furthest gas riser.
C. PUSH CAMERA
1. Where inspection cannot be completed using a lateral launcher, the Contractor will use a
push camera to complete the inspection or vice versa. The push camera is inserted at
cleanout and travels toward the wastewater main pipeline.
2. If branched laterals are encountered and identified as a location that cross the gas service
pipeline, the push camera will be initiated via an accessible cleanout to successfully clear the
branch lateral.
3. If a cleanout is not available, the Contractor may request City-approval to perform push
camera inspections through a roof vent.
a. The Contractor must provide the appropriate equipment to perform the push camera from
one to two stories above the grade. This includes ladders, harnesses, and any other
equipment required to safely perform the push camera inspection.
b. The Contractor is responsible for any damages that occurred during inspection through
a roof vent and the safety of their employees.
c. The Contractor shall not enter the property of the occupant nor access the roof vent of
the house or the building without the approval from the Project Engineer and the
presence of the City Inspector.
4. If a backwater valve is encountered in the sewer lateral, the Contractor may attempt to
inspect the sewer lateral by using a small diameter push camera, only if equipment damage
is unlikely and not limited by the backwater valve design configuration.
D. WATER JETTING AND MECHANICAL CLEANING
1. If an obstruction such as roots, debris, deposits, fat, oil, and grease prevents lateral launching
or using a push camera, the Contractor will perform hydro flushing as needed to allow
passage of the inspection camera and to capture acceptable quality video.
2. The Contractor will be responsible for providing all backpressure and backflow preventive
measures and equipment.
3. The Contractor will be responsible for all damages associated with sewer backup caused by
their cleaning activities.
4. The Contractor shall immediately notify the City in the event of any Sanitary Sewer Overflow
(SSO) associated with their cleaning activities. The Contractor is responsible for all costs
associated with the proper cleanup of SSO.
5. The City will not be responsible for the pre-cleaning of the wastewater mains. Therefore, the
Contractor may be required to pre-clean the wastewater main prior to sewer lateral
LEGACY CROSS BORE INSPECTION GUIDELINES SECTION 2741
CITY OF PALO ALTO: Legacy Cross Bore Inspection Guidelines Section 2741 PAGE 4
inspection.
E. HYDRO – EXCAVATION
1. If sag sections of sewer lateral are found during video inspection or if the sewer lateral cannot
be inspected in the potential cross bore area:
a. The Contractor must locate the alignment of the sewer lateral and gas service line using
sonde devices and pipe locator, respectively.
b. If the shortest distance between the gas service line and the sewer lateral is within three
(3) feet, the Contractor will perform potholing to determine if a potential cross bore exists.
2. Where gas pipelines cross branched laterals or wyes, the Contractor shall pothole at the
downstream point of connection to perform a video inspection of the branched lateral when
a push camera cannot be used to complete video inspection, see Figure 1.
WW Main
Gas Main
sewer lateral
branched lateral
gas service line
sewer cleanout
perform pothole
Gas service line cross branched laterals
Figure 1
3. The Contractor shall refer the Water, Gas, & Wastewater Utility Standards for excavation,
backfill, and restoration.
4. The Contractor shall only perform the potholing in the presence of the City Inspector.
5. The Contractor shall follow all established safety procedures as per CAL OSHA for digging
around underground utilities.
F. SURFACE MARKING
1. The Contractor shall place marking chalk or paint on paved surfaces and flags or feathers on
LEGACY CROSS BORE INSPECTION GUIDELINES SECTION 2741
CITY OF PALO ALTO: Legacy Cross Bore Inspection Guidelines Section 2741 PAGE 5
unpaved surfaces. The Contractor shall remove the markings placed by their forces.
2. Surface markings shall be placed at a maximum of five (5) foot intervals and at all locations
where there is a change in horizontal direction exceeding fifteen degrees (15o) when
locating the alignment of the sewer laterals and gas service pipelines.
3. All Underground Service Alert (USA) markings requested by the Contractor shall be
removed by the Contractor.
G. PIPE CONDITION
1. If severe pipe conditions exist such as root balls, broken pipe, and offset joints that prohibit
complete video inspection, the Contractor shall notify the City Inspector who shall determine
if it is on the City-owned lateral side or private lateral side.
a. Lower sewer lateral side - The Contractor and City Inspector shall notify CPAU
Engineering for repair.
b. Upper sewer lateral side – The Contractor and City Inspector shall notify CPAU
Engineering to provide notice to the property owner or representative.
2. Where a sag is encountered, the Contactor shall video inspect the sewer lateral from the
downstream point of connection and from the upstream access point to verify that a sag is
present. The Contractor shall pothole at the location of the sag to determine if a cross bore
exists.
3. Where a root ball is encountered, the Contractor shall hydro-flush the sewer pipe if it is
within 3-feet of the location of a gas pipe, to the satisfaction of the City Inspector. If the root
ball cannot be removed, the Contractor shall attempt to perform a reverse inspection.
Where a reverse inspection cannot be performed by the Contractor, the Contractor will be
required to hydro-excavate to determine if there is a cross bore at the location of the root
ball.
4. If the depth of flow exceeds 20% of the inside pipe diameter, the Contractor shall monitor
the sanitary pipes. If there is evidence the sanitary has low-flow conditions (≤ 20%) and
upon City approval, the Contractor would be permitted to adjust working hours. If high-flow
conditions (> 20%) persist, the Contractor will be requested to provide the necessary flow
control. Where flow control is required, the Contractor shall not plug pipes with the diameter
of 12-inches or larger.
5. Where a protruding lateral prohibit the Contractor from performing lateral launch, the
Contractor shall notify the City Inspector and provide a still-image of the protruding lateral
to CPAU Engineering. The still-image will be forwarded to CPAU Operations and its
removal will be scheduled. The Contractor will be notified when the protruding lateral is
removed.
H. INSPECTOR
1. The City Inspector will be on-site during all sewer lateral inspections.
2. The City Inspector will determine the necessary distance to safely clear the sewer lateral of
any potential cross bore.
3. The completion of a sewer lateral inspection will be left up to the discretion of the City
Inspector. If a sewer lateral inspection is complete, the Contractor shall not move to the next
inspection until instructed by the City Inspector.
LEGACY CROSS BORE INSPECTION GUIDELINES SECTION 2741
CITY OF PALO ALTO: Legacy Cross Bore Inspection Guidelines Section 2741 PAGE 6
4. The Inspector will verify the correct property to be inspected based on the package provided
to the Contractor.
I. PROXIMITY CLEARANCE
1. Upon City approval, the Contractor will be permitted to clear sanitary pipes by proximity if
other methods of inspection are unable to be performed.
J. EFFORT EXHAUSTED
1. The Contractor must exhaust all efforts as directed by the Engineer to determine if a cross
bore exists when existing conditions prevent the full inspection of the complete lateral.
2. If all attempts to video inspect the sewer lateral are unsuccessful and a proximity clearance
cannot be performed, the Contractor shall report the reason for effort exhausted to the City
after the last inspection attempt.
3. The Contractor will NOT be compensated for effort exhausted.
K. IDENTIFIED CROSS BORES
1. If an apparent cross bore is discovered, the Contractor shall take a still-image of the cross
bore location and submit it to the City Inspector for it to be included as a part of the daily
report and submit the Contractor’s Zoho form with the photo of the cross bore. The Inspector
will notify CPAU Engineering.
2. The Contractor shall mark the surface location of the apparent cross bore with marking paint.
a. If the gas pipe conflicting with the sewer pipe does not impede the inspection camera
and does not damage the gas pipe, the Contractor can continue inspection of the
sewer pipe until the video inspection is completed.
b. If the gas pipe conflicting with the sewer pipe impedes the inspection camera, the
Contractor shall stop the video inspection and notify the City Inspector.
3. CPAU Engineering will inform CPAU Operations and Maintenance to investigate the cross
bore.
4. Where a cross bore is found, CPAU Operations and Maintenance will schedule the
necessary repairs.
5. After the cross bore is repaired, the Contractor shall remobilize and resume the video
inspection work until it’s successfully completed.
L. REPORTING
1. The Contractor shall encode the condition assessment as per the NASSCO Standard of the
City-owned sewer lateral (lower sewer lateral) and electronic images of the sewer lateral
condition. The report will also include documentation of the footage traveled during sewer
lateral inspection.
2. The Contractor shall fill out and provide a Zoho Form report for cross bores and reasons for
an incomplete inspection with inspection pictures attached to the form.
LEGACY CROSS BORE INSPECTION GUIDELINES SECTION 2741
CITY OF PALO ALTO: Legacy Cross Bore Inspection Guidelines Section 2741 PAGE 7
3. If there are wyes or branched laterals encountered during inspections, the Contractor shall
document the inspection footage traveled in each wye or branched lateral.
4. A video of the inspection for each sewer lateral must be submitted by the Contractor. The
video must be in 19 x 20 MP4 file format.
5. All reports must be in PDF format.
6. All lateral launch and push camera videos and corresponding reports for the main lateral
shall be named the following:
Video Name:
“StreetName_House#_FID_MMDDYYYY” for one complete video of both the Private
lateral and City lateral.
OR
“StreetName_House#_FID_MMDDYYYY_PVT” and
“StreetName_House#_FID_MMDDYYYY_CITY” for two separate video reports of the
Private lateral and City Lateral
Report Name: “NASSCO_StreetName_House#_FID_MMDDYYYY”
For branched laterals or wyes from the main lateral requiring inspection (each address), the
videos and reports shall be labeled the following:
“StreetName_House#_FID_BL# or W#_MMDDYYYY_PVT”
7. All NASSCO and video reports shall be submitted at the end of each week to CPAU
Engineering for review.
M. QUALITY ASSURANCE (QA)/QUALITY CONTROL(QC)
1. The Contractor shall provide experienced work crews for data capture.
2. Frequent lens washing and lighting adjustments shall be included in order to obtain
acceptable video quality
3. Videos submitted for payment that exceeds the maximum travel speed will be rejected. The
Contractor will be directed to re-inspect the sewer lateral at no additional cost to the City.
4. The Contractor will provide coding of all City-owned sewer laterals at the time of video
inspection by a NASSCO LACP certified personnel.
5. The camera operator shall assess and shall indicate the status of the City-owned lateral
(lower sewer lateral) using NASSCO-compatible software.
6. In the event that the CPAU Engineering personnel discover a gas cross bore during the video
review, the Contractor will be instructed to re-inspect the sewer lateral at no additional cost
to the City.
7. The City shall reserve the right to cease all Contractor activities when the quality of work is
found to be unsatisfactory.
8. The Contractor shall indicate footage of sewer pipe inspected in deliverables. The footage
counter shall be displayed although out the video inspection.
LEGACY CROSS BORE INSPECTION GUIDELINES SECTION 2741
CITY OF PALO ALTO: Legacy Cross Bore Inspection Guidelines Section 2741 PAGE 8
9. The Contractor QC personnel shall review one hundred percent (100%) of all video
inspections.
PART 4 – SUBMITTALS
4.01 DELIVERABLES
A. The Contractor will provide the following deliverables on a weekly basis. The deliverables must
be submitted to the CPAU Engineering on the following Monday by 12:00 p.m.
1. Video
a. Acceptable individual video footage for each lower sewer lateral and each upper sewer
lateral. Video files must be submitted through a “cloud” storage online application.
b. Sanitary pipe inspection videos shall only be submitted for sanitary pipes that were
cleared of cross bore by the City Inspector at the time of inspection.
2. Forms
a. PACP Structural and O&M pipe assessment condition grading form for each inspected
lower sewer lateral. If a defect is identified in the lower sewer lateral, an image of the
defect must be included on the form.
b. WWOPS - LACP Checklist form for each lower sewer lateral.
c. Contractor Zoho forms per address inspected. The Contractor Zoho forms shall provide
required information about the inspection (property address, FID, total footage,
inspection details, and necessary pictures, attached to the form, regarding the
inspection)
3. Weekly cross bore spreadsheet for anticipated work. The spreadsheet will be provided by
the City and must be completed by the Contractor.
4. Weekly invoices for completed work to process progress payment. All invoices must be in
CPAU Engineering-approved format. The progress payment will be made at the end of each
month.
B. The Contractor must submit the latest calibration report of their equipment. The equipment must
be calibrated at least annually but may be calibrated at shorter intervals.
C. Upon the City’s request, the Contractor shall submit maintenance records for equipment used for
the inspection of sanitary pipes. The maintenance records include but are not limited to, truck,
generator, camera, etc.
END OF SECTION
TABLE OF CONTENTS Appendix A General Details
CITY OF PALO ALTO PAGE 1
Table of Contents
Appendix A
General WGW Utility Standard Details
Detail No. Title
WGW-01 Water, Gas & Wastewater Utility Configurations
WGW-02 Trench Backfill
WGW-02B Joint Gas Service Trench with Electrical
WGW-03 Trench Backfill for Shallow Mains
WGW-04 Pipe Casing and Vent Pipe
WGW-05A Residential Bollard
WGW-05B Commercial Bollard
WGW-06 Gas/Water Valve Concrete Collar and Steel Rebar in Existing Street
ALLOWED FOR RESIDENTIAL SERVICES ONLY
MARKER DETAIL
NOT TO SCALE
A-
CASING SEAL DETAIL
NOT TO SCALE
A-A-
A-A-
A-A-
”
TABLE OF CONTENTS Appendix B Water Details
CITY OF PALO ALTO PAGE 1
Table of Contents
Appendix B
Water Standard Details
Detail No. Title
WD-01A 2” HDPE Water Service (HDPE Main) with 5/8” or 1” Meter
WD-01B 2” HDPE Water Service (Non-HDPE Main) with 5/8” or 1” Meter
WD-01C 1” Copper Water Service Connection (Contaminated Soils)
WD-02A 2” HDPE Water Service (HDPE Main) with 1-1/2” or 2” Meter
WD-02B 2” HDPE Water Service (Non-HDPE Main) with 1-1/2” or 2” Meter
WD-02C 2” Copper Water Service (Contaminated Soils)
WD-03A 4” Thru 10” HDPE (HDPE Main) Domestic/Fire Service Connection
WD-03B 4” Thru 10” HDPE (Non-HDPE Main) Domestic/Fire Service Connection
WD-04 4” and 6” Water Meter Set with 2” By-Pass
WD-05A 2” HDPE Water Service (HDPE Main) with Two 5/8” or 1” Meters
WD-05B 2” HDPE Water Service (Non-HDPE Main) with Two 5/8” or 1” Meters
WD-06A 2” Water Service Manifold (HDPE Main) with Two or Four 5/8” or 1” Meters
WD-06B 2” Water Service Manifold (Non-HDPE Main) with Two or Four 5/8” or 1” Meters
WD-07A 2” HDPE Water Service Tap HDPE Domestic or Fire Service
WD-07B 2” HDPE Water Service Tap Existing Non-HDPE Fire Service
WD-08 Combination Fire/ Domestic Water Service Connection
WD-09 Combination Fire/Domestic Water Service Connection (Multiple Meters)
WD-10 Armorcast Meter Box (30”x48”) with Multiple Headers
WD-11A 3” or Larger Reduced Pressure Principle Assembly – RPPA
WD-11B Parallel Reduced Pressure Principle Assembly
WD-11C Reduced Pressure Principle Assembly – RPPA (3/4”-2”)
WD-12A Reduced Pressure Detector Assembly RPDA For Fire Services and Sprinklers
WD-12B Reduced Pressure Detector Assembly RPDA For Inside Installation
WD-12C Residential Double Check Valve Assembly - DCVA (1”-2”)
WD-13 Thrust Block Table
WD-14 Gate Valve Assembly
WD-15 Fire Hydrant Assembly with HDPE Pipe
WD-16 Fire Hydrant or Service Abandonment
WD-17 Vertical Bends HDPE Pipe Connecting to Non-HDPE Pipe
WD-17A Vertical Bends PVC or DI Pipe Connecting to Non-HDPE Pipe
WD-18 Valve Tie-Back During Construction
WD-19 2” Blow-Off Valve for Dead End HDPE Mains Up to 12”
WD-19A 2” Blow-Off Valve for Dead End Non-HDPE Mains Up to 12”
WD-20 Cut & Cap Existing Main
WD-21 Air Release Valve
WD-22 New Gate Valve (Installation on Exist. Main)
TABLE OF CONTENTS Appendix C Gas Details
CITY OF PALO ALTO PAGE 1
Table of Contents
Appendix C
Gas Standard Details
Detail No. Title
GD-01A 1” Gas Service with 1” EFV
GD-01B 1” Gas Service with 1-1/4” EFV
GD-01C 2” Gas Service with EFV
GD-01D 2” Gas Service without EFV
GD-02A Residential Diaphragm Gas Meter Clearance 250-800 SCFH
GD-02B Residential Diaphragm Gas Meter Clearance 1,000 SCFH
GD-02C Residential Rotary Gas Meter Clearance 1,100-1,500 SCFH
GD-03A Residential Meter Set Assembly 250-800 SCFH
GD-03B Residential Meter Set Assembly 250-800 SCFH
GD-04A Residential Manifold Meter Set Assembly w/o Bypass 500 SCFH
GD-04B Residential Manifold Meter Set Assembly w/o Bypass 500 SCFH (List of Materials)
GD-04C Residential Manifold Meter Set Assembly w/ Bypass 1,000 SCFH
GD-04D Residential Manifold Meter Set Assembly w/ Bypass 1,000 SCFH (List of Materials)
GD-05A Residential/Commercial Manifold Meter Set Assembly Up To 1,250 SCFH
GD-05B Residential/Commercial Manifold Meter Set Assembly Up To 1,250 SCFH (List of Materials)
GD-06A Residential/Commercial Manifold Meter Set Assembly 1,500 - 3,000 SCFH
GD-06B Residential/Commercial Manifold Meter Set Assembly 1,500 - 3,000 SCFH (List of Materials)
GD-07A Residential/Commercial Manifold Meter Set Assembly 3,000 - 5,000 SCFH
GD-07B Residential/Commercial Manifold Meter Set Assembly 3,000 - 5,000 SCFH (List of Materials)
GD-08A Residential/Commercial Manifold Meter Set Assembly 5,000 to 15,000 SCFH
GD-08B Residential/Commercial Manifold Meter Set Assembly 5,000 to 15,000 SCFH (List of Materials)
GD-08C Residential/Commercial Manifold Meter Set Assembly 5,000 to 15,000 SCFH (Est. Pressure Loss)
GD-09A Residential/Commercial/Industrial Rotary Meter Set Assembly 800–2,000 SCFH
GD-09B Residential/Commercial/Industrial Rotary Meter Set Assembly 800–2,000 SCFH
GD-09C Residential/Commercial/Industrial Rotary Meter Set Assembly 800–2,000 SCFH
GD-10A Commercial Meter Set Assembly 250 - 425 SCFH
GD-10B Commercial Meter Set Assembly 250 – 425 SCFH
GD-11A Commercial Meter Set Assembly 630-800 SCFH
GD-11B Commercial Meter Set Assembly 630-800 SCFH
GD-12A Commercial Meter Set Assembly 1,000 SCFH
GD-12B Commercial Meter Set Assembly 1,000 SCFH
GD-13A Commercial/Industrial Rotary Meter Set Assembly 2,000-3,000 SCFH
GD-13B Commercial/Industrial Rotary Meter Set Assembly 2,000-3,000 SCFH
GD-14A Commercial/Industrial Rotary Meter Set Assembly 5,000 & 7,000 SCFH
GD-14B Commercial/Industrial Rotary Meter Set Assembly 5,000 & 7,000 SCFH
GD-14C Commercial/Industrial Rotary Meter Set Assembly 5,000 & 7,000 SCFH
GD-15A Commercial/Industrial Rotary Meter Set Assembly 5,000-7,000 SCFH
GD-15B Commercial/Industrial Rotary Meter Set Assembly 5,000-7,000 SCFH
GD-15C Commercial/Industrial Rotary Meter Set Assembly 5,000-7,000 SCFH
TABLE OF CONTENTS Appendix C Gas Details
CITY OF PALO ALTO PAGE 2
GD-16A Commercial/Industrial Rotary Meter Set Assembly 11,000 SCFH
GD-16B Commercial/Industrial Rotary Meter Set Assembly 11,000 SCFH
GD-17A Commercial/Industrial Rotary Meter Set Assembly 11,000/16,000 SCFH
GD-17B Commercial/Industrial Rotary Meter Set Assembly 11,000/16,000 SCFH
GD-17C Commercial/Industrial Rotary Meter Set Assembly 11,000/16,000 SCFH
GD-18A Industrial Rotary Meter Set Assembly 23,000 SCFH
GD-18B Industrial Rotary Meter Set Assembly 23,000 SCFH
GD-18C Industrial Rotary Meter Set Assembly 23,000 SCFH
GD-19A Industrial Ultrasonic Meter Set Assembly 16,000-25,000 SCFH
GD-19B Industrial Ultrasonic Meter Set Assembly 16,000-25,000 SCFH
GD-19C Industrial Ultrasonic Meter Set Assembly 16,000-25,000 SCFH
GD-19D Industrial Ultrasonic Meter Set Assembly 16,000-25,000 SCFH
GD-20A Industrial Ultrasonic Meter Set Assembly 23,000-45,000 SCFH
GD-20B Industrial Ultrasonic Meter Set Assembly 23,000-45,000 SCFH
GD-20C Industrial Ultrasonic Meter Set Assembly 23,000-45,000 SCFH
GD-20D Industrial Ultrasonic Meter Set Assembly 23,000-45,000 SCFH
GD-20E Industrial Ultrasonic Meter Set Assembly 23,000-45,000 SCFH
GD-21 Curb Gas Meter 250-630 SCFH
GD-22 Multiple Curb Gas Meters 250-630 SCFH
GD-23A Utility Box (Curb Location) Meter Set Assembly 250 SCFH
GD-23B Utility Box (Curb Location) Meter Set Assembly 250 SCFH
GD-23C Utility Box (Curb Location) Meter Set Assembly 400-630 SCFH
GD-23D Utility Box (Curb Location) Meter Set Assembly 400-630 SCFH
GD-24A Commercial Curb Gas Rotary Meter 800-2,000 SCFH Utility Box (Curb Location)
GD-24B Commercial Rotary Meter Set Assembly 800-1,100 Utility Box (Curb Location)
GD-24C Commercial Rotary Meter Set Assembly 800-1,100 Utility Box (Curb Location)
GD-25A Commercial Rotary Meter Set Assembly 1,500-2,000 SCFH Utility Box (Curb Location)
GD-25B Commercial Rotary Meter Set Assembly 1,500-2,000 SCFH Utility Box (Curb Location)
GD-25C Commercial Rotary Meter Set Assembly 1,500-2,000 SCFH Utility Box (Curb Location)
GD-26A Commercial/Industrial Curb Gas Rotary Meter 2,000-3,000 SCFH Utility Box (Curb)
GD-26B Commercial/Industrial Rotary Meter Set Assembly 2,000-3,000 SCFH Utility Box (Curb)
GD-26C Commercial/Industrial Rotary Meter Set Assembly 2,000-3,000 SCFH Utility Box (Curb)
GD-26D Commercial/Industrial Rotary Meter Set Assembly 2,000-3,000 SCFH Utility Box (Curb)
GD-27A Commercial/Industrial Curb Gas Rotary Meter 5,000-7,000 SCFH Utility Box (Curb)
GD-27B Commercial/Industrial Rotary Meter Set Assembly 5,000-7,000 SCFH Utility Box (Curb)
GD-27C Commercial/Industrial Rotary Meter Set Assembly 5,000-7,000 SCFH Utility Box (Curb)
GD-27D Commercial/Industrial Rotary Meter Set Assembly 5,000-7,000 SCFH Utility Box (Curb)
GD-28A Gas Service Regulator Vent Extension Assembly
GD-28B Gas Service Regulator Vent Extension Assembly
TABLE OF CONTENTS Appendix D Wastewater Details
CITY OF PALO ALTO PAGE 1
Table of Contents
Appendix D
Wastewater Standard Details
Detail No. Title
WWD-01A Sanitary Sewer Lateral
WWD-01B Sanitary Sewer Lateral with Backwater Valve Protection Type 1
WWD-01C Sanitary Sewer Lateral with Backwater Valve Protection Type 2
WWD-02A Sanitary Sewer Cleanout Type 1
WWD-02B Sanitary Sewer Cleanout Type 2
WWD-03 Sanitary Sewer Cleanout Box Type 1
WWD-04 Sanitary Sewer Cleanout Box Type 2 (Traffic Area)
WWD-05 Sanitary Sewer Lateral - Main Connections
WWD-06 Sanitary Sewer Lateral Connection with Tap-Tite
WWD-07A Sanitary Sewer Manhole (For New Pipes 36” and Less)
WWD-07B Sanitary Sewer Manhole (For Existing Pipes 36” and less)
WWD-08A Sanitary Sewer Manhole (For New Pipes Larger Than 36”)
WWD-08B Sanitary Sewer Manhole (For Existing Pipes Larger Than 36”)
WWD-09 Sanitary Sewer Manhole Outside Drop
WWD-10 Sanitary Sewer Manhole Frame and Cover