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HomeMy WebLinkAbout1998-01-12 City CouncilTO: FROM: City of Palo Alto City Manager’s Report HONORABLE CITY COUNCIL CITY MANAGER DEPARTMENT:UTILITIES 8 DATE: SUBJECT: JANUARY 12, 1998 CMR:101:98 AMARILLO AVENUE AND EMBARCADERO WAY RELIEF SEWER PROJECT -APPROVAL OF MITIGATED NEGATIVE DECLARATION, FINAL PROJECT ALIGNMENT, AND RIGHT-OF- WAY ACQUISITION REPORT IN BRIEF This report requests that Council adopt the Negative Declaration, approve the proposed relief trunk sewer route and expenditures of $160,000 for the purchase of necessary temporary and permanent rights-of-way and easements. The proposed project will construct approximately 4300 linear feet of 42 inch relief sewer from Amarillo Avenue to Embarcadero Way. Microtunneling, bore and jack and open trench construction methods are planned for the project. Staff anticipates completing the final design and returning to Council in July, 1998 for the award of the construction contract. Funds for the design, rights-of-way acquisition and construction are in the FY 1997-98 Wastewater Collection System Rehabilitation!Augmentation CIP 9173. CMR:101:98 Page 1 of 5 RECOMMENDATION Staff recommends that Council: Adopt the Negative Declaration with a finding of no significant environmental impact (Attachment A); Approve staff’s recommendation on proposed relief sewer route for the project contained in the Initial Study and Negative Declaration for Amarillo Avenue and Embarcadero Way Relief Sewer Project (Attachment A); and Approve expenditure of funds in the amount of $160,000 for the purchase of the necessary rights-of-way for the project. BACKGROUND In 1988, Camp Dresser & McKee completed the Master Plan of the Wastewater Collection System (Master Plan) for Palo Alto’s sanitary sewer collection system. The Master Plan indicated certain trunk main facilities were in need of capacity relief to carry peak wastewater flows and recommended improvements to correct these collection system deficiencies. One of the recommended major capacity relief projects in the Master Plan is a capacity relief sewer construction project that crosses US 101 at Amarillo Avenue, continues on East Bayshore Frontage Road to a City bike path, follows the bike path aligrmaent, crosses under the edge of the City Baylands Nature Preserve and ties into a manhole in an easement near Embarcadero Way. The existing major sewer trunk main is located in the central part of the City’s collection system and conveys more than 50 percent of the City’s wastewater flow to the Regional Water Quality Control Plant. To minimize disruption to the public, traffic flow, and the environment, a trench less construction method, microtunneling, will be used to install major portions of the relief sewer pipeline. The sewer pipe alignment which crosses under the Bayshore Freeway, US 101, will be bored and jacked into place. The alignment portions which cross under the Palo Alto Baylands and private property will use microtunneling technology. The alignments on Amarillo Avenue and East Bayshore Road will have the bid option of being microtunneled or traditional "open cut" construction. Microtunneling technology involves the excavation of construction pits from which the pipeline is installed beneath the ground surface. The construction pits are used to launch and retrieve the microtunneling equipment. Unlike traditional open trench pipeline construction methods, which can involve substantial surface disruption and related traffic flow problems, the only surface disruption with microtunneling is the building of the construction pits and.the micr0tunneling work at these pits. CMR:101:98 Page 2 of 5 On September 30, 1996, Council approved a consultant agreement with Kennedy/Jenks Consultants, Inc., in the amount of $301,000 for the design of the Amarillo Avenue and Embarcadero Way Relief Sewer Project (CMR:410:96). On May 5, 1997, Council approved Amendment No. 1 for surveying services and a limited update of the Master Plan, authorized staff to proceed with preliminary right-of-way discussions on private property for rights-of- entry and preparation of easement descriptions, authorized staff to proceed with geotechnical investigations in public rights-of-way and in easements on private property, and supported staff’s recommendation on CEQA documentation for the project (CMR:221:97). Staff anticipated returning to Council in July 1997 to ask Council to approve the proposed relief sewer route, for authorization of funds to acquire the necessary easements, and to certify the CEQA Initial Study/Negative Declaration. The project was delayed for several reasons. The original alignment recommended for approval was modified due to findings in the geotechnical investigations. Additional soil borings needed to be performed and analyzed as a result of [he revised alignment. The revised alignment also resulted in the need for additional surveying services and additional time for preparation of new easements for the project. Staff has now completed this additional work. DISCUSSION Kennedy/Jenks’ subconsultants have completed the surveying of the proposed route and the necessary easement descriptions for the acquisition of these easements. A geotechnical~ investigation was conducted through a subconsultant, Woodward-Clyde Consultants. As the proposed alignment design was developed, the length of each microtunneling segment was established. Based on the geotechnical lab test data, the sucbonsultant performed engineering analysis to develop recommendations regarding the geotechnical aspects of open .cut trenching and microtunneling methods. These recommendations will be incorporated in the final design for the proposed project route. The Initial Study/Negative Declaration (IS/ND) work was performed by Kennedy/Jenks’ subconsultant, CH2M HILL. A notice regarding the IS/ND for the project was sent to all property owners and occupants within a 300 foot radius of the project alignment on November 3, 1997. A public notice of a project Negative Declaration was also published in the Palo Alto Weekly on November 7, 1997. The public review period of 30 days ended December 8, 1997. Copies of the IS/ND were also sent to the State Clearinghouse for Environmental Documents for distribution to various State agencies for comment, in accordance with CEQA. CMR:101:98 Page 3 of 5 One comment letter was received from the public in response to the notice for the IS/ND. The topics of concern in the letter included the location of the proposed new relief.sewer, status of a public easement on and adjacent to the project alignment, .disruption of normal and customary use of a building on a property adjacent to the proposed project alignment, surface drainage concerns, and structural integrity of a building on a property adjacent to the proposed project alignment, surface drainage concerns, and structural integrity of a building on a property adjacent to the proposed project alignment. Although not required under CEQA, a response to these issues was prepared and mailed to’ the commentor. Copies of the comment letter (Attachment B) and staff response (Attachment C) are attached to this staff report. The value of the temporary and permanent fights-of-way required for the project has been appraised by a State-certified General Real Estate Appraiser. Based on this appraisal, staff estimates costs to acquire tlae necessary fights-of-way for the project will not exceed $160,000. RESOURCE IMPACT Sufficient funds for this project are included in the FY97-98 Capital Improvement Program budget for Wastewater Collection System Rehabilitation/Augmentation (CIP Number 9173). POLICY IMPLICATIONS This report does not represent any change to existing City policies. TIME LINE Staff anticipates completing the final project design, preparing bid documents, bidding the project and returning to Council by July 1998 for award of the construction project. The construction of the project will be completed by March 1999. ENVIRONMENTAL REVIEW An environmental assessment has been prepared, and the Negati.ve Declaration of no significant environmental impact is attached to this report. CMR:101:98 Page 4 of 5 , ATTACHMENTS Attachment A: Attachment B: Attachment C: Initial Study and Negative Declaration for Amarillo Avenue and Embarcadero Way Relief Sewer Project Letter from Michael J. Ackerman Staff response letter to Michael J. Ackerman PREPARED BY: Roger W. Cwiak DEPARTMENT HEAD: Jo Director of Utilities CITY MANAGER APPROVAL: , EMIL"~"-H ARR~ 61(I Assistant City Manager CMR:101:98 Page 5 of 5 Attachment "A" NOTICE ~0F AVAILABILITY AND NOTICE OF PUBLIC MEETING INITIAL STUDY AND NEGATIVE DECLARATION FOR AMARILLO AVENUE AND EMBARCADERO WAY RELIEF SEWER PROJECT TO:All Interested Parties DATE: October 31, 1997 FROM:City of Palo Alto, Utilities Dept. 250 Hamilton Avenue Palo Alto, CA 94301 SUBJECT:NOTICE OF AVAILABILITY AND NOTICE OF PUBLIC MEETING FOR INITIAL STUDY AND NEGATIVE DECLARATION FOR THE AMARILLO AND EMBARCADERO WAY RELIEF SEWER PROJECT LEAD AGENCY: CONTACT: City of Palo Alto, Utilities Department 250 Hamilton Avenue Palo Alto, CA 94301 Edward Wu, Senior Engineer Public notice is hereby given that the City of Palo Alto Utilities Department has prepared an Initial St.udy/Negative Declaration (IS/ND) for the proposed Amarillo and Embarcadero Way Relief Sewer Project, and the IS/ND is available for public review. The Relief Sewer Project involves the construction of a 42-inch relief sewer in a portion of Amarillo Avenue, East Bayshore Road, and other private and public properties in Palo Alto. The need for this project was identified in the City’s 1988 Wastewater Collection System Master Plan. The existing 36-inch sewer line extends from the southwest corner of Greer Park in Amarillo Avenue, under the Bayshore Freeway (U.S. 101), and under the Baylands Nature Preserve to the Palo Alto Regional Water Quality Control Plant, and was identified as not having sufficient capacity to accommodate expected wastewater flows in the year 2000. The proposed project will provide a 42oinch sanitary sewer to relieve the existing 36-inch trunk sewer. The project description and location, along with a discussion of potential environmental effects that may occur as a result of project implementation, are contained in the attached Initial Study/Negative Declaration, pursuant to Article 6 (Negative Declaration Process) of the California Environmental Quality Act (CEQA) Guidelines. PUBLIC HEARING: The Palo Alto City Council will conduct a public hearing on the proposed IS/ND at its regular meeting on Monday, December 15, 1997. The meeting will be held at 7:00 p.m. in the City Council Chambers at 250 Hamilton Avenue, Palo Alto, CA 94301. RESPONSES: Due to limits mandated by State law, your response to this notice must be sent no later than 30 days after receipt. Based on our mailing, this 30 day period will run from November 3 to December 3, 1997. PLEASE SENDYOURRESPONSESTO: Mr. Edward Wu, Senior Engineer, at the address shown above. Please remember to include your name and/or the name of the contact person in your agency. We will be pleased to receive your input and comments. Please contact Mr. Wu at (650) 329-2126 should you need more information. CITY OF PALO ALTO -ENVIRONMENTAL CHECKLIST FORM 1. Project Title: Amarillo Avenue and Embarcadero Way Relief Sewer Project 2. Lead Agency Name and Address: City of Palo Alto Utilities Department 250 Hamilton Avenue Palo Alto, CA 94301 3. Contact Person and Phone Number: Edward Wu, Senior Engineer (650) 329-2126 4. Project Location: Amarillo Avenue and East Bayshore Road in Palo Alto, California 5. Application Number(s): Not applicable. 6. Project Sponsor’s Name and Address: 7. General Plan Designation: City of Palo Alto Utilities Department 250 Hamilton Avenue Palo Alto, CA 94301 Edward Wu, Senior Engineer Not applicable. 8. Zoning: Not applicable. 9.Description of the Project: The project evaluated in this Initial Study/Negative Declaration (IS/ND) is a 42-inch relief sewer to be constructed in Amarillo Avenue, East Bayshore Road, and other private and public properties in Palo Alto. The need for this project was identified in the City’s 1988 Wastewater Collection System Master Plan (Camp Dresser & McKee, 1988). The 1988 Plan recommended a Capital Improvement Program (CIP) to address the wastewater system’s current and expected capacity deficiencies through the year 2000. The existing 36-inch diameter trunk sewer line extending from the southwest comer of Greet Park in Amarillo Avenue, under the Bayshore Freeway (U.S. 101), and under the Baylands Nature Preserve to the Palo Alto Regional Water Quality Control Plant (PA.RWQCP) was identified in 1988 as having insufficient flow capacity, using a 5-year storm event. Studies performed by the City in 1996 indicated that the additional required capacity can be provided by constructing a new 42-inch diameter sewer line to relieve the existing 36-inch diameter trunk sewer. The existing trunk sewer carries flow from the lower basin area of Palo Altoidentified as Basin B07 in the Master Plan (the area encircling the intersection of East Meadow Drive and Louis Road). The sewer system in Basin B07 has experienced significant surcharging during periods of heavy rainfall. Though recent CIP projects have reduced the potential of manholes overflowing, surcharging still occurs during storm events. The relief sewer project, along with other improvements included in the City’s CIP, are designed to correct capacity deficiencies and to convey the wastewater flows anticipated in the year 2000. J :\WOR K\ 139139\lSFORM I .doc I Several alignment options were evaluated for locating the relief sewer project. To identify the preferred alignment for the project, a series of workshops were held to discuss the feasible options, define the criteria that would be used to evaluate the alternatives, determine weighting factors, and rank the alternatives to identify the best apparent solution. These workshops were usually attended by City staff from the following departments or divisions: ¯Utilities Engineering ¯Regional Water Quality Control Plant ¯Field Operations ¯Planning and Community Environment ¯Real Estate ¯Recreation, Open Space & Sciences The design team for the project identified the feasible altematives for conveying the flow to the Palo Alto Regional Water Quality Control Plant. These alternatives were discussed at the first workshop and a decision matrix was developed that considered the short term construction impacts and the longer term operation and maintenance issues associated with each alternative. Weighting factors for each impact were also established. The design team then developed the feasible altematives for the project and applied the decision criteria with weighting factors to each alternative. Through this process, it was determined that the best solution was an alignment that parallels the existing 36-inch sewer at the beginning and end of its alignment, but goes around the edge of the Baylands Nature Preserve in the middle segment; it was also determined that trenchless construction technologies should be used to minimize the construction-related impacts in the project area. This alignment was then selected and work was initiated to secure the necessary easements and geotechnical investigations for the project. The proposed relief sewer will begin at City manhole #21-4-16 in Amarillo Way near Greer Park, and .travel eastward adjacent to an existing 15-inch diameter sanitary sewer under U.S. 101 to East Bayshore Road. The alignment continues north to parallel the existing 15-inch diameter sanitary sewer in East Bayshore Road for about 730 feet, where it tums eastward along an existing pedestrian path located between two office buildings. The alignment then crosses eastward underneath the northwest comer of the Baylands Nature Preserve from the end of the pedestrian path to a point at the rear of an office building parking lot west of Faber Place, and then to the parking lot at the rear of The Harbor Business Park located southeast of Faber Place. The alignment then traverses east through the parking lot to parallel the existing 36-inch trunk sanitary sewer, and terminates at City manhole #15-1-18 located in the parking lot approximately 220 feet west of Embarcadero Way. A junction box structure will be required at the beginning and end of the alignment to connect to the existing 36-inch diameter trunk sewer. Figure 1 shows the project vicinity. Figure 2 shows the relief sewer schematic design, and Figure 3 shows an aerial photograph of the project area. The proposed alignment was developed to avoid conflicts with existing utilities while maintaining service in the existing sewers. Criteria for the separation of water mains and sanitary sewer mains have been incorporated into the design. To minimize disruption to the public, traffic flow, and the environment, trenchless construction methods (including microtunneling) will be used to install major portions of the relief sewer pipeline. J:\WORK\I39139~ISFORM 1 .doc 2 The alignment portions which cross the Bayshore Freeway, the Baylands Preserve, and The Harbor Business Park will use microtunneling technology. The alignments in Amarillo Avenue and East Bayshore Road will have the option of being microtunneled or traditional "open cut" construction. Microtunneling technology involves the excavation of "jacking" and "receiving". pits, from which the pipeline is pushed (or "jacked") underground from one pit and received at another pit. The only surface disruption with this technology is related to construction activities which take place at the jacking and receiving pits; unlike traditional "cut and cover" (or trench) methods, which can involve substantial surface disruption and related traffic flow bottlenecks), microtunneling is performed underground, with virtually no surface disruption. The proposed locations of jacking and receiving pits are shown in Figure 2. Schematic drawings of typical jacking and receiving pit configurations are shown in Figure 4. Jacking pits are typically about 12 to 15 feet wide and 20 feet long, for a total area of 240 to 340 square feet. Receiving pits are usually smaller than jacking pits, and measure approximately 10’ x 10’ o.r 12’ x 12’ square. The entire pit staging area would be approximately 2,500 to 4,000 square feet in area. The newly-installed pipe would be located approximately 12 feet below ground surface. This depth is at a sufficient elevation so as not.to .affect the ground surface and tree roots above. There is virtually no surface vibration from the microtunneling activity. The total length of the relief sewer is approximately 4,334 feet, with an overall slope of 0.11 percent. The relief sewer will be completed in eight segments. The pipe material for the alignment will need to be resistant to corrosion and will be selected in a competitive bidding process, except for the U.S. 101 crossing, which will likely be T-lock lined reinforced concrete cylinder pipe; steel casing may also be required for this crossing. Actual construction of the project is anticipated to last approximately 6 months. When completed, the Amarillo Avenue and Embarcadero Way Relief Sewer Project will meet the City’s Wastewater Master Plan and CIP goals by providing the capacity that the wastewater collection system needs to convey design flows during major storm events. 10. Su~’rounding Land Uses and Setting: Following is a description of the land uses and setting along the various segments of the pipeline alignment. Amarillo Avenue - Greer Park is located on the southeast side of Amarillo Avenue, and apartment complexes and units are located on the northeast side. Single-family residences line both sides of Amarillo Avenue west of Greer Park. West Bayshore Road, which parallels the west side of Bayshore Freeway, is lined with apartment complexes on its west side and a freeway sound wall on its east side. Large eucalyptus and cypress trees line the southwest side of Amarillo Avenue in Greer Park. ¯East Bayshore Road - Commercial office buildings are located along both sides of East Bayshore Road. High tension PG&E wires and towers are located along the northeast side of this road. Pedestrian Path - The pipeline will turn eastward from East Bayshore Road and be installed underneath an existing pedestrian path that provides recreational access from East Bayshore Road to the Baylands Preserve. Both sides of the path are abutted by parking lots and offices, and are landscaped with ornamental species, including oleander and eucalyptus. J :\WORK\ 139139\ISFORM I .doc 3 Baylands Nature Preserve - The pipeline will run underneath the Baylands Preserve which in this location, consists primarily of open space and marsh vegetation. This portion of the Preserve does not typically contain water from the bay. The pedestrian path described above, along with its continuation to the terminus of Faber Place, provide access to the Preserve from East Bayshore Road and Faber Place. Although access to some portions of the path may be temporarily restricted due to construction activities, alternate pedestrian and bicycle access routes will be identified and remain open during project construction. ¯Harbor Business Park - The final leg of the pipeline will be located at the rear of the Harbor Business Park, where parking lots and ornamental landscaping are the primary land use features. 11. Other public agencies whose approval is required (e.g. permits, financing approval, or participation agreement): Various encroachment permits will be required for the project, including encroachment permits for construction in city rights-of-way, a permit from Caltrans for the U.S. 101 crossing, possible encroachment or other permits from other utilities (such as PG&E, Brooks Fiber Optic, etc.). Temporary construction easements and permanent public works easements will be required from a few private property owners in the project vicinity. The following approvals will be required for the pipeline construction underneath the Baylands Nature Preserve: a) Park Improvement Ordinance from City of Palo Alto; 2) Letter of Permission from the U.S. Army Corps of Engineers; and 3) Notice of Intent to Proceed from the San Francisco Bay Conservation and Development Commission. In addition, the California Department of Fish and Game and the U.S. Fish and Wildlife Service will be notified of the project to solicit their input on issues relating to threatened/endangered species. J :\WORK\ 139139\ISFORM l.doc PALO ALTO MUNICIpAl. Scale: 1"= 2,900 Feet // MTN. VIEW Figure 1 Vicinity Map CH2MHILL ~ 5 Environmental Issues Information Sources (see list on page 1 5) Potentially Significant Issues Potentially Significant Unless Mitigation Incorporated Less Than Signifi- cant Impact No Impact 1. LAND USE AND PLANNING. Would the proposal: a)Conflict with general plan designation or zoning?1 b)Conflict with applicable environmental plans or 1, 6 policies adopted by agencies with jurisdiction over the Pr.0Ject? ...... c)Be incompatible with existing land use in the 1 vicinity? d)Affect agricultural resources or operations (e.g.1 impact to soils or farmlands, or impacts from incompatible land uses)? e) Disrupt or divide the physical arrangement of an 1 established community (including a low-income or minority community)? 2.POPULATION AND HOUSING. Would the proposal: a) Cumulatively exceed official regional or local 1 x population projections? b) Induce substantial growth in an area either directly 1 x or indirectly (e.g. through projects in an undeveloped area xor major infrastructure)? c) Displace existing housing, especially affordable 1 housing? 3.GEOLOGY, SOILS, SEISMIClTY: Would the proposal result in or expose people to potential impacts,involving: a)Fault rupture?1, 2 x b)’Seismic ground shaking?1, 2 x c)Seismic ground failure, including liquefaction?1, 2 x d)Seiche, tsunami, or volcanic hazard?’1, 2 x e)Landslides or mudflows? .....1,"’2 ’x f)Erosion, changes in topography or unstable s0il 5 x conditions from excavation, grading or fill? ’g)Subsi(~’~nce of the lan’d? ..............5 ...........x ’h)’Expansive soils?5 x" i)Uniqu~ geologic or physical features?1, 2 x :\WORK\139139~lSFORM I .doc I 0 Environmental Issues Information Sources (see list on page 15) Potentially Significant ~ssues Potentially Significant Unless Mitigation Incorporated Less Than Signifi- cant Impact No Impact 4.WATER. Would the proposal result in: a) Changes in absorption rates, drainage patterns, or 3 x the rate and amount of surface runoff? b) Exposure of people or property to water ~lated 2 x hazards such as flooding? 3 xc)Discharge into surface waters or other alteration of surface water quality, including but not limited to temperature, dissolved oxygen, turbidity or other typical storm water pollutants (e.g. sediment and debris from construction, hydrocarbons and metals from vehicle use, nutrients and pesticides from landscape maintenance)? d) Changes in the amount of surface water in any water body or wetland? 3 x e") Changes in currents, oi’ the course or’direction of 3 x water movements, in marine or freshwater, or wetlands? 3 xf)Change in the quantity of ground waters, either through direct additions or withdrawals, or through interception of an aquifer by cuts or excavations or through substantial loss of groundwater recharge capability? g) Altered direction or rate of flow of groundwater? h) Impacts to groundwater quality through infiltration of reclaimed water or storm water runoff that has contacted pollutants from urban or industrial activities? i) Substantial reduction in the amount of groundwater otherwise available for public water supplies? 3 3 3 3j)Alteration of wetlands in any way? 5.AIR QUALITY. "Would the proposal: x x x a)Violate any air quality standard or contribute to an 2 x exiting or projected air quality violation? b)Expose sensitive receptors to pollutants?2, 3 c)Alter air movement, moisture, or temperature, or 2 x cause any change in climate? xd)Create objectionable odors?2, 3 J:\WORK\139139\ISFORMI .doc 11 Environmental Issues 6.TRANSPORTATION/CIRCULATION. Information Sources (see list on page 1 5) Would the proposal result in: Potentially Significant Issues Potentially Significant Unless Mitigation Incorporated Less No Than Impact Signifi- cant Impact a)Increased vehicle trips or traffic congestion? b)Hazards to safety from design features (e.g. sharp curves or dangerous intersections) or incompatible uses (e.g.. farm equipment)? c) uses? d) e) f) Inadequate emergency access or access to nearby Ins~’fficient parking Capacity on-site or off-site? ¯ Hazards or barriers for pedestrians or bicyclists? Conflicts with adopted policies s~pporting 3 1,2 1,2 alternative transportation (e.g. bus turnouts, bicycle racks)? g)Rail, waterborne or a.ir traffic’impacts?1’12 7.BIOLOGICAL RESOURCES. ~Would the proposal result in reduc’tion or interference in: a) Endangered, threatened or rare species or their habitats (including but not limited to plants, fish, insects, animals or birds)? 2,4,6 b) forest, d) e) 8. Locally designated species (e.g. heritage tree~’i? Loc’ally designated natural communities (e.g. oak coastal habitat, etc.)? Wetland habitat (e.g. marsh, riparian, vernal P0ol?) Wildlife dispersal or ’migration co’r~idors? ENERGY AND MINERAL RESOURCES. Would the pro 1,2 1’,2 )osal: x x x x x x x x x a)Conflict with adopted energy conservation plans? b) Use non-renewable resources in a wasteful and inefficient manner? 1 3 x x c) Result in the loss of availability of a known mineral 1 x resource that would be of future value to the region and the residents of the State? 9.HAZARDS. Would the proposal involve: 3 xa)A risk of accidental explosion or release of hazardous substances (including, but not limited to: oil, pesticides, chemicals or radiation)? J:\WORK~ 139139\lSFORM 1 .doc 12 Environmental Issues b) Possible interference with an emergency response plan or emergency evacuation plan? c) The creation of any health hazard or potential health hazard? d) Exposure of people to existing sources of potential health hazards? e) Increased fire hazard in areas with flammable brush, grass or trees? Information Sources (see list on page 15) 1,3 1,3 Potentially Significant Issues Potentially Significant Unless Mitigation .....Incorporated Less ’No " Than Impact ’Signifi- cant Impact x x x X 10. NOISE. Would the proposa! result in: a) b) Increase in existing noise levels? Exposure of people to severe noise levels? x x 11. PUBLIC SERVICES. Would the proposal have an effect upon, or result in a need for new or altered government services in any of the following areas: a) b) c) d) Fire protection? Police protection? Schools? Maintenance of public facilities, including roads or 1 1 1 1,3 storm drain facilities? e)Other governmental services?1 1’2. UTILITIES AND SERVICE SYSTEMS. Would the proposal result in a need for new systems or supplies, or substantial alterations to the following utilities: a)Power or natural gas? b)Communications systems? )Locai’ 0’r regional’wate~ treatment or distribution facilities~ 1,3 x x x x X X X d)Sewer or septic tanks?1, 3 x e)Stormwater drainage or stormwater quality?1, 3 X f)Solid waste disposal?1, 3 x g)Local or regional water supplies? ....11 3 ’ ’x .I :\WORK\139139XISFORM 1 .doc ,13 Environmental Issues Information Sources (see list on page 1 5) Potentially Significant Issues Potentially Significant Unless Mitigation Incorporated Less Than Signifi- cant Impact Impact a) .Does the project have the potential to degrade the quality of the environment, substantially reduce the habitat of a fish or wildlife species, cause a fish or wildlife population to drop below self-sustaining levels, threaten to eliminate a plant or animal community, reduce the number or restrict the range of a rare or endangered plant or animal or eliminate important examples of the major periods of California history or p.~eh!story? b)Does the project have the potential to achieve short- term, to the disadvantage of long-term, environmental goals? 13. AESTHETICS. Would the proposal: a)Affect a scenic vista or scenic highway?1, 2 x b)Have a demonstrable negative aesthetic effect?1, 2 x c)Create light or glare?3 x 14.CULTURAL RESOURCES. ’Would the proposal: a)Disturb paleontological resources?1, 2 ’x b)Disturb archaeological resources?1, 2 x c)Affect historical resources?1, 2 x d) Have the potential to cause a physical change 1, 2 x which would affect unique ethnic cultural values? e) Restrict existing religious or sacred uses within the 1, 2 x potential impact area? 15. RECREATION. Would the proposal: a) Increase the demand for neighborhood or regional x parks or other recreational facilities? b)Affect existing recreational opportunities?x 16. MANDATORY FINDINGS OF SIGNIFICANCE. X c) Does the project have impacts that are individually limited, but cumulatively considerable? ("Cumulatively considerable" means that the incremental effects of a project are considerable when viewed in connection with the effects of past projects, the effects of other current projects, and the effects .of probable future projects) d) Does the project have environmental effects which will cause substantial adverse effects on human beings, either directly or indirectly? X J:\WORK\139139\ISFORM 1 .doc 14 17, INFORMATION SOURCES 1 Draft Palo Alto Comprehensive Plan, 1996~2010, Embracing the New Centuryi 2 ’graf~ Enviionmental Impact Report for Palo Alto ComPrehensive ’Plan Update, prepa’~ed for City Of Palo Alto by Brady and....As.sociates, December 1996. ............3 ....Task 5 Schematic Design Submittal for the Amarillo Avenue/Embarcader~ Way Relief Sewer Project, prepared for the City of Palo Alto bY Kennedy/Jenks Consultants, April 1997. 4 Te.lephone conversation with Stephen J. Klein, Woodward-Clyde Consultants, on April 8, 1997. 5 Geotechnical investigation’ for the Amari"ilo Av’en"’~e and Embarcadero way Relief Sewer Project, Palo /~lto, California, prepared by Woodward Clyde Consultants September 1997. 6 ’Baylands Nature Preserve Master Plan, adopted by City of Palo Alto in 19’78.’ 7 Conversation and field visit with Palo Alto City Arborist, David Sandage, April. 21, 1997. J:\WORK\ 139139’dSFORM 1 .doc 15 19.EXPLANATIONS FOR CHECKLIST RESPONSES 1 b Approximately 1,000 feet of the relief sewer would be located underneath the northwesternmo~t portion of the Baylands Nature Preserve. The preserve is owned by the City and is zoned for public facilities. The preserve has one of the largest undisturbed areas of native marsh vegetation, endangered species habitats, and habitats for waterfowl and shorebirds in the South Bay. Recreational facilities for the Baylands Preserve have been planned and implemented.through the Baylands Master Plan, which was adopted by the City in 1978. The Master Plan is a detailed plan that seeks to balance ecological preservation of the area with controlled commercial and recreational use of the area. The relief sewer would be installed underneath this portion of the preserve using microtmnneling technology; a jacking/receiving pit would be located approximately at the mid- point of the 1,200-foot length, about 500 feet west of the end of Faber Place. It is possible that access to the pedestrian/bicycle path in this location may be temporarily restricted by construction activities associated with this pit, but there would be no surface disruption of the preserve itself. After construction is completed in this vicinity, the pipeline would not be visible, and there would be a manhole on the north side of the pathway. Construction activities in this vicinity wilJ be coordinated with the City’s Recreation, Open Space & Sciences Division, and may require temporary signage to direct pathway users of alternate routes to access the Preserve. Because there would be no permanent affects on the Preserve, the project would not COrLflict with the Baylands Master Plan. 1 c Although construction activities may cause short-term temporary disruption to some land uses in the vicinity of the pipeline project, the project itself would not be incompatible with existing land uses. ’" 2b The relief sewer project is not growth-inducing because it does not provide additional capacity to or expansion of sewer collection or treatment infrastructure in Palo Alto. The relief sewer is designed and intended to provide flow capacity for peak storm events. 3a Based on available information, no active faults are located in the immediate project vicinity; therefore, the likelihood of surface rupture or fault creep along the proposed alignment is considered remote. 3b The Palo Alto Comprehensive Plan designates"the proj’ ci"area to be prone to very violent shaking in the event of a major earthquake. This shaking could cause significant damage to underground infrastructure if not properly designed and constructed. A geotechnical report for the project has been prepared and is available for public review at the City Utilities Department’ at the address listed on the front page of this document. The recommended seismic design measures identified in that report will be incorporated into the project to reduce potential seismic impacts to a less than significant level. Liquefaction can occur when loose, ~aturated, rel~tivei~’ dean cohesionless soils are subjected ’to ........ ground vibrations. The geotechnical investigation prepared for the project indicates that the soil conditions in the project vicinity consist primarily of day soils, with occasional sand and gravel layers. The day layers are judged not to be susceptible to liquefaction, but there is some potential for liquefaction to occur in the medium dense sand and gravel layers encountered at some boring locations. Design measures will be incorporated into the project to address liquefaction issues. 3~ ’ ’Tsunami, ~eiche, or volcanic hazard are geologic problems not associated with’the San Francisco Bay and its environs. Therefore, this does not represent a significant impact to the project. J:\WORK\139139’~ISFORM 1 .doe ¯16 3f 3g The project vicinity is relatively flat, so landslides and/or mudflows would not occur and no impact would result. Excavation and fill activities would be associated with the microtunneling jacking and receiving pits. Excavation and subsequent fill of these pits will be performed in accordance with standard construction practices, which include protective measures to prevent erosion and unstable soil conditions. Temporary shoring will be utilized, in accordance with recommendations contained in the geotechnical investigation. Based on the available subsurface data, it is anticipated"th~’t the ground conditions that will be encountered during microtunneling will consist mainly of soft to very stiff alluvial clays, interbedded with loose to medium dense alluvial sands and gravels. These ground conditions indicate the need for positive groundwater control during construction and special microtunneling equipment to minimize the loss of ground and surface settlement. Although no land subsidence is anticipated, either during or after pipeline installation, special design and construction measures, as recommended in the geotechnical investigation, will be incorporated into the project to reduce potential geotechnical impacts to a less than significant level. 3h See response to Item 3g above. 3i There are no unique geologic or physical features in the project vicinity. 4c 4d Construction activities could temporarily cause surface runoff to storm drains ~r adjacent properties. However, pursuant to RWQCB permit requirements, a Stormwater Pollution Prevent Plan (SWPPP) will be developed and implemented for the project. The plan will include a description of all construction practices that would be employed to control pollutants in stormwater discharges. The SWPPP will be submitted to and reviewed by the City Public Works Department to ensure that suitable specifications are included in the plan. The project will not involve any disruptions to surface waters or wetlands. For the jacking/receiving pits located near the pedestrian path and Baylands Nature Preserve, the marsh and wetlands areas will be dearly delineated to the contractor, and no construction activity will be permitted in the Preserve itself. In addition, erosion control measures will be used to prevent accidental discharge of construction materials to wetlands. 4e See response to Item 4d above. Shallow groundwater in the project vicinity was encountered in all test borings at depths ranging between 4 !6 to 616 feet below present ground surface. The shallowest groundwater depths measured in the borings are typically within or just above the Bay Mud layer. It is anticipated that the groundwater level will be about 10 to 15 feet above the bottom of the proposed pipe trench; therefore, a dewatering system will be installed to minimize groundwater infiltration into the microtunneling operation. The dewatering system will be designed and implemented in accordance with the recommendations of the geotechnical investigation. 4]See response to Item 4d above. 5b An increase in dust and emissions from heavy’machinery and truck traffic is expected during project construction. This could create a temporary air quality impact to nearby residents and businesses. To reduce this impact to a less than significant level, construction equipment will be properly maintained and tuned, engine idling will be minimized, regular street cleaning will be conducted, and Construction zones will be watered as appropriate to reduce construction dust. Trucks hauling dirt will also be covered. J:\WORK\I39139~ISFORM 1 .doc 7b With microtunneling technology, approximately 6-8 trucks per day would arrive and depart from the jacking pits with pipe delivery, and approximately 6-8 trucks per day would arrive and depart from the same pits carrying waste or slurry spoils. Construction spoils would be taken t6 a nearby landfill. While this truck traffic increase is not considered significant and would not add to traffic congestion, the trucks would represent a different type of vehicular movement on the local Palo Alto streets (particularly Amarillo Avenue) where construction would occur. The construction contractor will be required to prepare and implement a traffic management plan for construction activities that have the potential to disrupt traffic flow or affect neighboring properties, and to identify appropriate travel routes for trucks. Both West Bayshore and East Bayshore Roads are designated through truck routes in the City of Palo Alto, so construction trucks would be limited to these routes. Truck access to the Amarillo Avenue construction area should be directed to West Bayshore Road, rather than Greer Road. Bicycle travel is an important component of the transportation system that Connects Palo Alto, Menlo Park, Mountain View, and Stanford University. Bicycle facilities are defined as: Class I - bike path (an exclusive right-of-way for bicyclists and pedestrians, with cross flows .of motorists minimized); Class II - bike lane (an area designated by lane striping within the paved roadway that is restricted to bicycle and moped use); Class III- bike route (a right-of-way, usually a paved street, designated by signs that is shared by bicycle and motor vehicle traffic, and where bicycle usage is encouraged); shared roadway (no bikeway designation, usage of any street by bicyclists unless specifically prohibited); and bicycle boulevard (a local street on which bicycle travel is given precedence, and on which impediments to bicycle travel are removed or minimized). Designated bike routes in the project vicinity include the following: ¯East Bayshore - on-street bike lane and off-road bike path ¯West Bayshore - on-street bike lane ¯Amarillo and Greer Avenues - signed bike route ¯Oregon Avenue or Oregon frontage road (between Greer and U.S. 101) - on-street bike lane ¯Pedestrian path off East Bayshore - off-road bike path Construction activities have the potential to affect these nearby bicycle facilities. The traffic management plan discussed in Item 6a above will include measures to protect bicyclists and pedestrians from construction activities and traffic, and to provide for adequate bicycle movement. As indicated in Item #1b above, a portion of’the relief sewer would be located underneath the northwesternrnost portion of the Baylands Preserve. The Preserve contains significant native marsh vegetation and endangered species habitat. Prior to construction of the jacking/receiving pits near the pedestrian pathway, the limits of the marsh will be clearly delineated and protected from construction activities. Therefore, there would be no surface disruption to any part of the preserve, and no endangered, threatened, or rare species or their habitats would be affected by the project. No heritage trees ’would be affected by the project. The microtunneling activity ~ould occur about 8 to 14 feet beneath the ground surface, with an average of 11 feet of cover. Tree root systems along the alignment are expected to reside in the first 3 feet of cover, and roots are not expected at more than 6 feet of depth, especially with the reduced oxygen available at deeper elevations. Therefore, tree roots along the alignment would not be affected by the microtunneling activity. ’See response to Items #1b and #7a above. .1 :\WORKM 39139\ISFORM 1 .doc 98 9b ’"10a Chemicals such as gasoline, diesel, fuels, lubricating oils, hydraulic oil, lubricating grease, automatic transmission fluid, paints, and solvents may be used during construction activities. An accidental spill of any of these substances could occur during construction of the project. Handling and storage of fuels and other flammable materials is governed by the California Occupational Safety and Health Administration (CAL/OSHA) standards. Construction documents will include a Substance Control Program for construction activities to reduce and prevent the potential for chemical spills. This program will require the safe collection and. disposal of hazardous substances generated during construction activities, and will include an Emergency Response Program to ehsure quick and safe cleanup of accidental spills. The project would not interfere with an emergency response or evacuation plan. However; because some project construction would occur within City rights-of-way, some traffic obstruction, including emergency vehicle travel, may be affected. The contractor will be required to obtain permits for construction in City rights-of-way, and will notify the City regarding which streets may be affected.. It is not anticipated that the pipeline construhtion will enc0unter’contaminated soils or g.roundwa~er. In addition, the primary method of pipeline installation will be via trenchless technology; therefore, the potential for construction workers to come into contact with potentially contaminated materials would be minimized. Nonetheless, the contractor will be required to prepare and implement a health and safety plan which will include protocols to be followed in the event that contaminated soils or groundwater are encountered. The project would result temporary increased noise levels during Construction, but no long-term noise increases from operations. Sensitive receptors to construction noise include the residences and Greet Park along Amarillo Avenue, office building employees along East Bayshore Road and in The Harbor Business Park, and animals inhabiting the Baylands Preserve. Construction activities associated with the project would include earth-moving equipment required for excavating and filling the microtunneling pits, the microtunneling machinery itself, and truck traffic associated with the microtunneling activity. Construction activities and microtunnelin.g operations may generate noise levels around 85 to 90 dBA. According to the City’s Noise Ordinance (City of Palo Alto Municipal Code, Chapter 9.10), construction activities that are authorized by a city permit are allowed between 8:00 a.m. and 8!00 p.m. Monday through Friday; 9:,00 a.m. and 8:00 p.m. on Saturday;~and 10:00 a.m. and 6:00 p.m. on Sundays and holidays, if the construction activities meet at least one of the following requirements: No individual, piece of equipment may produce a noise level exceeding 110 dBA at a distance of 25 feet. ¯The noise level at any point outside the property plane of the project must not exceed 110 dBA. Construction on residential property shall be allowed only during the hours between 8:00 a.m. and 6:00 p.m. Monday through Friday; 9:00 a.m. and 6:00 p.m. on Saturday; and 10:00 a.m. and 6:00 p.m. on Sundays and holidays. The contractor will be required to comply with City noise standards during project construction in both residential and non-residential areas. If construction activities require exceptions to the noise standards or ordinance, appropriate permits will be obtained. 10b The noise levels from construction activities ~uld p0tentialiy be c~nsidered severe by adjacent sensitive receptors, although they would be temporary. As noted in Item #10a above, construction activities will be required to comply with all applicable City noise standards and ordinances. J:\WORK\139139~ISFORM 1 .doc 19 11d 1 2c 12d 13b 14a-e 15b The proposed relief sewer would be required to be maintained by the City of Palo Alto. This is n0~ a significant impact on City services. The project would n~t require any modifications to the Palo Alto Regional Water Quality Control Plant, or any other pipelines in the City’s sewage collection system. See response to Item #11c above. The project would be located underground, with no visible components on the ground surface except manholes. There would be no change to the visual environment in the project vicinity after construction is completed. The portion of the p~oject located adjacent to and west ~’f the Bayshore Freeway is considered to be an area of "Moderate Sensitivity" for archaeological resources in Palo Alto. Areas east of the freeway are considered to have low archaeological sensitivity. There are no known archaeological or historical resources in the project construction area. However, in the event that cultural resources are discovered during construction activities, all .work would cease, and a qualified archaeologist would be consulted to determine the significance of the findings. Recreational users of Greer ’Park and the pedestrian path leading from East Bayshore Roadthrough the Nature Preserve to Faber Place (under which the relief sewer would be located) could be temporarily affected by project construction activities. Greer Park users may be affected by construction noise, but there would be no construction activities within the park itself. The pedestrian path may need to be temporarily restricted to bicyclists and pedestrians during construction activities. If access to the path needs to be restricted, users would be directed by temporary signage to alternate routes in the Preserve vicinity. Pathway closures, notices to users, and temporary signage will be coordinated with the City’s Recreation, Open Space and Sciences Division. Impacts to recreational users are considered short-term temporary impacts related to construction only; no long-term effects to the Preserve would occur. Any damage to the pedestrian/bicycle path due to construction activities shall be repaired, and the path reconstructed to City standards. Pre- and post-construction surveys of the pathway will be performed; after construction, the City Engineer will use the surveys to determine if the pathway has been restored to its original condition. J :\WORK\ 139139’dSFORM 1 .doc 20