HomeMy WebLinkAbout2003-03-10 City CouncilCity of PaRo ARto
C ty Manager’s Report
TO:
FROM:
DATE:
TITLE:
HONORABLE CITY COUNCIL
CITY MANAGER
MARCH 10, 2003
DEPARTMENT: UTILITIES
CMR: 115:03
CITY OF PALO ALTO UTILITIES CAPITAL IMPROVEMENT
PROGRAM (CIP) - STATUS REPORT
This is an informational report and no Council action is required. This report provides
the City Council with an overview and update on the status of the ongoing efforts to
up~ade and rehabilitate the City of Palo Alto Utilities (CPAU) under~ound facilities
and discusses how CPAU and the Public Works Department coordinate work in city
streets.
DISCUSSION
CPAU is undertaking a major capital improvement program (CIP) to improve the
capability, reliability and esthetics of utility systems. The systems include water, natural
gas, electric distribution and the wastewater collection system. Each system has unique
operating characteristics that require specific engineering and construction practices. At
the conclusion of World War II, the growth in Palo Alto increased dramatically resulting
in large portions of the infrastructure being 40 to 50 years old today. Consequently, a
substantial number of the utility distribution systems are near or at the end of their useful
lives.
Water
The City’s water utility was founded in 1896.
consists of:
~ 226.2 miles of water mains
The water distribution system presently
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19,335 meters
6 reservoirs
5 booster pump stations
5 standby (3 operational) wells
Mains
o Prior to 1960:140 miles
o 1960- 1980:47.5 miles
o 1980 to present: 38.7miles
Pipe Materials
o 120.9 miles of asbestos cement pipe (ACP)
o 49.3 miles of cast iron pipe (CIP)
o 17.3 miles of concrete cylinder pipe (CCP)
o 38.7 miles of polyvinyl chloride pipes (PVC)
As the water distribution system ages, it is necessary to replace specific water mains and
accessories. Some mains are inadequate in size to supply required flows and pressures
for fire protection; others are subject to recurring breaks.
In 1989, the cast iron portion of the water distribution system (about 35 percent of the
water system) began experiencing frequent and recmxing breaks due to both external and
internal corrosion. These cast iron mains were mostly installed between 1904 and 1956.
Hence, in FY 1991/92 the 26-year cast iron main replacement program was launched to
replace old and corroded cast iron mains as well as other mains subject to recun~ng
breaks. CPAU is also replacing existing water mains that have been detern~ined to be
undersized and inadequate to supply the required flows and pressure for fire protection.
In addition to replacing deteriorating and deficient water mains, CPAU is
rehabilitating/up~’ading existing reservoirs, wells and pumping stations, as well as
building new wells and reservoirs. These current and planned infrastructure
improvements will greatly enhance the water distribution system reliability, reduce the
cost of maintenance and repair, preser~;e system water quality, and help prepare for
potential water supply emergencies.
Since the water main replacement program began in 1991, over 32 miles of new PVC
water mains have been installed. On average, three miles of new PVC water mains are
installed each year.. With the current replacement cycle, the number of breaks on the cast
iron portion of the system has held steady. As the cast iron pipes age, the frequency of
breaks increases and essentially offsets the decreased breaks from replacing bad sections.
None of the new PVC sections have failed. It is expected that a decrease in the overall
number of breaks will be achieved as more cast iron is replaced with PVC.
CMR: 115:03 Page 2 of 8
On the Water Main Replacement Project 15, the total design, construction and other
related costs to date are approximately $21,700,000 or $678,125 per mile. This cost
includes system connections, new valves, new fire hydrants, and reconnections of
existing services. These costs are expected to increase at about 3% per annum. It will
take an additional 15 years to complete the water main replacement pro~am (by FY
2016/17) at an additional cost of approximately $40,400,000. Without taking into
consideration inflation changes, the total estimated expenditures to complete the pro~am
will amount to $62,100,000.
Natural Gas
Municipal operation of the gas system began in
presently consists of:
1917.The gas distribution system
209 miles of mains
200 miles of service lines
19,059 services
23,101 meters
Mains
.t9!7 to 1956:83 miles
~1956- 1963:51 miles
.1963- 1986:29 miles
o 1986- Present: 46 miles
Gas lnains must be replaced when leaks present a potential safety hazard or when leak
repairs are no longer cost effective. The accelerated replacement of high priority mains
will result in fewer leaks and public safety concerns. It will also result in lower long-
term maintenance costs.
Since the infrastructure replacement pro~am began in 1991, 35.8 miles of main and
2,884 smwice lines have been replaced. In FY 1992/93 the amount of main replaced was
increased from 7,000 to 20,000 lineal feet (lf) per year. In IVY 1999/00, the amount of
main replaced was again increased from approximately 20,000 to 30,000 If per year due
to the improved efficiency associated with directional drilling methods and the reduction
in associated excavation/backfill and paving expenses. The construction impacts in the
neighborhoods were also greatly reduced with the introduction of directional drilling
rnethods.
For the completion of Gas Main Replacement Project (GMR) 11, and the design phase of
GMR 12, the total design, construction and other related costs to date is approximately
$25,349,000.
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To complete the replacelaent of the high priority mains (approximately 39.77 miles or
210,000 linear feet), it will take an additional six GMR projects (to GMR 18) to complete
construction in 2009 at an additional cost of approximately $30,725,000. The
replacement pro~am reduces the City’s exposure to significant ABS pipe failure.
Without taking into consideration inflation changes, the total estimated expenditures to
complete the program will amount to $56,074,000.
Waste Water Collection System
The development of the wastewater collection system (sewers) dates back to 1898, when
a bond issue was approved to construct a sanitary sewer system. Over the years, the
wastewater collection system has been expanded to accomrnodate growth in the service
area.
Wastewater System Infrastructure:
203 miles of wastewater main pipe
17,245 service connections
82 miles of service lines
3,400 sewer structures in the system (manholes,
cleanouts)
lampholes, flushing inlets, and
Age of Wastewater Mains:
,1899-1935:60 miles
o 1935-1965:90 miles
e 1965-1988:50 miles
e 1988-present: 3 miles
Pipe Materials Used:
, Vitrified clay pipe (VCP) for nearly all of the sewer mains smaller than 14 inches
in diameter
, Reinforced concrete (RC) for most of the pipelines larger than 14 inches
, Vitrified clay pipe (VCP) for selwice laterals
Wastewater collection systems have a design tife of about 50 years. The CPAU
wastewater collection system is an aging infrastructure with a number of operational
challenges. Because the system dates back to the end of the 19th century, much of the
system was constructed to older desig-n standards and lower pipe material requirements.
New standards require extra strength VCP.
CMR: 115:03 Page 4 of 8
Over the years, this system has also been subjected to a number of earthquakes, the
effects of solids deposition, tree root intrusion, grease accumulation, structural defects,
system overloading, corrosion, and deterioration. Additionally, many of the existing
manholes are constructed of brick and mortar and show signs of deterioration. All of
these conditions contribute to a significant and costly water infiltration and inflow
problem that can cause hydraulic overloading of both the sanitary sewer system and
wastewater treatment facilities.
The Wastewater CIP pro~’am encompasses both rehabilitation and augmentation. In
general, sewer systems do not last for their desig-n life and thus require rehabilitation
before the end of their desig-n life. Rehabilitation tries to restore sewers to their original
life expectancy. In contrast, augmentation work involves capacity enhancement of the
wastewater collection system to handle increased use and peak wastewater flow. In
1989, a Wastewater Collection Master Plan for the entire sanitary sewer collection
system was conducted. This analysis, along with the Inflow/Infiltration flow study,
provided the basis for CPAU’s 20-year CIP Rehabilitation/Augmentation Wastewater
Program. On March 1, 1990 (CMR: 183:0), the Council adopted the current 20-year CIP
Rehabilitation!Augmentation Pro~am.
Sewer rehabilitation, construction of flow diversions, new developments, and other
operational improvements have no doubt altered the flows and hydraulics in the system.
An update of the Wastewater Collection Master Plan is underway to help CPAU
effectively plan for future system improvements.
The rehabilitation work classified as having significant structural defects is included in
the 20-year CIP Program. Significant structural defects include missing pieces, gaps in
the line, and large cracks. The early years of the 20-year program concentrated on the
most cost effective infrastructure projects, i.e., diversion structures and rehabilitation
projects before the augmentation projects. The 20-year period for the program allowed
CPAU to spread the costs of the pro~am over a number of years so that annual costs
remain relatively uniform and at a reasonable rate for the customer.
The five main objectives of the \VW Collection System Rehabilitation/Augmentation
Program are:
1.Rehabilitate all the pipes that are classified as structurally defective.
2.Increase the capacity of certain facilities to handle peak wastewater flow.
3.Minimize and/or eliminate wastewater overflows from the collection system.
4.Construct and maintain an accurate computerized database of the collection
system.
Continually monitor the effectiveness of the pro~am and to make changes as
needed.
CMR: 115:03 Page 5 of 8
Since the 20-year CIP Rehabilitation/Augmentation Wastewater Pro~am began in 1990,
171,416 linear feet or 32.5 miles of main have been replaced or rehabilitated. In the early
years of the CIP program, work was concentrated in the rehabilitation area to obtain the
most cost effective use of the money. Through the completion of Project 11 Sanitary
Sewer Rehabilitation Project, the total construction costs to date are approximately
$35,460,000. To complete the current 20-year CIP Rehabilitation!Augmentation
Wastewater Program, it will take an additional 9 years (FY 2010/11) at an additional cost
of approximately $35,595,000 or $4 million per year. Without taking into consideration
inflation changes, the total estimated construction costs to complete the pro~am will
amount to $71,055,000.
Electric
The electric utility was founded in !900.The Fiber Optic syst;m was added in 1996.
Electric Infrastructure
o 12 substations
o 186 miles of underground lines
,227 miles of overhead distribution
,17 miles of 60kV sub-transmission
,_8,28a meters
o 89 traffic siN~al intersections
o 6,240 streetlights
Fiber Optic Infrastructure
*31.5 route miles of fiber plant
o 15.75 miles of overhead fiber plant
.15.75 miles of underground fiber plant
,101 commercial buildings connected.
The electric infrastructure rebuilding CIP is comprised of three major parts: the
rebuilding of the overhead system, the replacement of overhead with under~ound
facilities, and the rebuilding of existing underground facilities. In the traffic signal CIP
there is a major project to replace obsolete traffic signal controllers.
The rebuilding of the overhead system has two components: pole replacement and
voltage conversion. The pole replacement pro~am is intended to extend the useful life
of the existing overhead system by replacing poles that are near or at the end of their life
cycle. There are approximately 3,800 near the end of their useful lives. Over the last five
years replacements have been made at an average of 134 poles per year. The goal for the
next 15 years is to replace 200 poles per year at an estimated annual expenditure of $1
million. The remaining poles are expected to be removed as part of the undergrounding
CMR: 115:03 Page 6 of 8
of overhead facilities. Voltage conversion, the changing of the system voltage from
4,000 volts to 12,470 volts, results in energy savings and increased public safety.
System Undergrounding: The systematic under~ounding of the high voltage distribution
system began in the early 1960s. Approximately one-third of the system has now been
installed under~ound through either new construction or converting existing overhead
lines. There are two facets to under~ounding of the system. The first is to build
under~ound systems to replace existing overhead systems and the second is to
rehabilitate and upgrade underground systems that have reached the end of their useful
life.
The life expectancy of existing high voltage under~ound distribution cables and
connections are 30 years and approximately 238,000 feet of cable has reached its
expected life span. The cable replacement program began in 1995, and since that time
75,755 feet have been replaced. Another 88,000 feet are expected to be replaced in the
next five years.
The first section of the electric system to be converted to underground was completed in
1965; since then, 38 of 150 planned underground districts have been formed and
completed. All underground districts are formed by ordinance as adopted by the Council.
Districts are formed as needed to meet equipment replacement cycles and design
schedules.
The size and priority of the under~ound districts is determined by a number of factors
including age, condition of the system, and Council priorities. The rate at which facilities
are placed under~’ound is dictated by the availability of funds, staff time, and contractors
to do the work, in addition to avoiding congestion with other utility projects.
In the last 5 years, $7,100,000 has been spent to under~’ound 337 residential addresses.
Over the next 5 years CPAU expects to spend $9,200,000 million to underground another
338 addresses. The $7,100,000 and $9,200,000 million figures are budgeted amounts.
Approximately 40% is reimbursable from other entities (SBC and AT&T) that share in
the under~-ounding of an area. It is impossible to estimate with any accuracy the time or
costs to complete the undergrounding of all overhead lines.
Utilities and Public Works Proiect Coordination
The Public Works (PW) Engineering and Operations divisions are responsible for city
streets including storm drains, curbs, gutters and sidewalks and street pavement. The
City’s Infrastructure Management Plan includes the annual replacement of broken or
damaged curbs, gutter and sidewalk and annual street resurfacing (paving) projects.
CPAU and PW staff coordinate projects on Palo Alto’s streets to avoid trenching
operations where new pavement has been recently placed whenever practical.
CMR: 115:03 Page 7 of 8
The City’s Geographic Information System (GIS) is used as a too! to coordinate and
avoid scheduled installation conflicts between CPAU infrastructure projects and PW
street projects. Staff can identify where future projects are scheduled and whether they
are to be located in the same area as other planned projects. Conflicts be~veen projects
can be easily identified and unnecessary cutting of new paving surfaces can be avoided
by scheduling paving work after scheduled undergrounding work is completed. PW staff
also provides input to the GIS on street excavation permits from both private developers
and utility projects to assist in coordination with PW street projects.
Although CPAU and PW staffs schedule projects to avoid unnecessary cutting of new
pavement surfaces, there are times when this cannot be avoided. Examples may include
when unanticipated emergency repairs are needed on under~ound utilities or storm
drains, when outside agencies such as telecommunication companies perform work on
streets that have recently been repaved, and when new development projects are
submitted and approved that require new utility and storm drain connections. In these
instances the parties responsible for the unanticipated trenching are required to restore the
pavement surface to City standards.
RESOURCE IMPACT
The funding for CIP projects comes from the associated enterprise funds. Each enterprise
fund is based on revenues from customers charged for utility services. CPAU will use
revenue bonds to fund some of the upcoming water and gas system improvement
projects. Al! funding is authorized tl~’ough the bi-annual City budget approval process.
POLICY IMPLICATIONS
The CIP program is consistent with the Council approved Utilities Strategic Plan
Supporting Objective No. 2 to "Invest in utility infrastructure to deliver reliable se~wice,"
and Strategy No. 1 to "Operate distribution systems in a cost effective manner."
PREPARED BY:Scott Bradshaw
Ed Wu
Tomm Marshall
Greg Scoby
Roger Cwiak
Romel Antonio
DEPARTMENT HEAD:
CITY MANAGER APPROVAL:
?r of Utilities
EMIl HARRISON
Assistant City Manager
CMR: 115:03 Page 8 of 8