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HomeMy WebLinkAbout2007-05-21 Ordinance 4952ORDINANCE NO. 4952 ORDINANCE OF THE COUNCIL OF THE CITY OF PALO ALTO APPROVING AND ADOPTING PLANS FOR IMPROVEMENTS TO EL CAMINO PARK The Council ofthe City of Palo Alto does ORDAIN as follows: SECTION 1. Findings. The City Council finds and declares that: (a) Article VIn of the Charter of the City of Palo Alto and Section 22.08.005 of the Palo Alto Municipal Code require that, before any substantial building, construction, reconstruction or development is commenced or approved, upon or with respect to any land held by the City for park purposes, the Council shall first cause to be prepared and by ordinance approve and adopt a plan therefor. (b) EI Camino Park is dedicated to park purposes. (c) The City intends to authorize construction of a new 2.5 million gallon (MG) water storage reservoir and associated pump station in El Camino Park, and new well, as shown on the El Camino Park Reservoir and Well Development Area, the El Camino Park Typical Reservoir Construction Layout and the EI Camino Park Reservoir, Pump Station, and Well Construction Plan (collectively "Plans") attached as Exhibits "A-1 ", "A-2" and "A-3" including, without limitation, the following: 070531 syn6050143 (1) Construction of a new below-grade 2.5 million gallon water storage reservOIr. (2) Construction of a new pump station, including a new well, which will replace the existing Lytton Station. The structure will consist of an above-and below--grade structure which will house the production well facilities and equipment. The above-ground portion of the main structure would be of a similar size as the existing structure, approximately 26 feet by 44 feet wide, and 17 to 25 feet high. (3) Installation of underground piping connecting the underground reservoir to the pump station, turnout, and well facility. (4) Installation of underground piping connecting the reservoir to the existing water distribution and storm water systems. (5) Installation of an access hatch, approximately 50 square feet in area, on top of the reservoir and buried below ground level such that it does not occupy any playing field. 1 (6) Clearing of vegetation and trimming of existing trees in accordance with City policies and as necessary to provide equipment access for construction. (d) Passage of this ordinance is contingent upon Council approval of the property acquisition of the appropriate property rights to the project site. (e) Passage of this ordinance is also contingent upon the vote on the November 2007 advisory ballot measure concerning the use of EI Camino Park for the placement of the water storage reservoir and associated pump station and well facilities. (f) The improvements at EI Camino Park will not alter the existing location and square footage of the existing athletic fields. Upon completion of construction, existing park uses, including the baseball and soccer fields, will be restored and improved with new facilities. (g) The improvements will avoid existing protected trees located along the perimeter of the park and will be either contained within existing structures and fences or buried below-grade, causing no reduction in park area. (h) The improvements described above and as more specifically described on the Plans attached hereto as Exhibits "A-I", "A-2" and "A-3" are consistent with park and conservation purposes. (i) The Council desires to approve the projects described above and as more specifically described on the Plans attached hereto as Exhibits "A-I ", "A-2" and "A-3". SECTION 2. The Council hereby approves the Plan for replacement and construction of improvements in EI Camino Park and hereby adopts the Plans attached hereto as Exhibits "A-I", "A-2", and "A-3" as part of the official plan for the construction of improvements in EI Camino Park. SECTION 3. The Council finds that the projects to construct new facilities at EI Camino Park are subject to review under the California Environmental Quality Act (CEQA) A Draft Environmental Impact Report for this project was prepared and circulated on November 8, 2006, and a Final Environmental Impact Report for this project was prepared and circulated On February 8, 2007. II II II II II 2 070531 syn 6050143 SECTION 4. date of its adoption. This ordinance shall be effective on the thirty-first day after the INTRODUCED: PASSED: AYES: NOES: ABSENT: ABSTENTIONS: March 05, 2007 May 21, 2007 BARTON, BEECHAM, DREKMEIER, KISHIMOTO, MORTON, MOSSAR CORDELL, KLEIN, KLEINBERG APPROVED AS TO FORM: ~ CityAtt ey inistrative Services 3 070531 syn 6050143 DevelOpment Area o Potsntlal Utility Connection Locations ~ Regulaled Tree Pr<lIE!c:t1on Zone (TPZ) pa2!l7Il~ Notes: ,. Undelllrcund utility rout .. and aoooss routes 10 be finalized during preliminary design. Routes to be mitiga!ad per Tree Protection Report and d .. igned 10 avoid sensitive resources and existing facilities to the extent feasible. 2. Please refer to F.gure 2.13 for a typical layout of the proposed reservoir facilities. 3. Regulated tn>es (Including protected oaks and redwoods). street 11_ in the rightoQl.woy and signlficant d .. ignated trees (Olympic Grove Redwoods. man"" saeening trees, etc.) are present. 4. Perimeter_ are regulated~ ExhibitA-1 EL CAMINO PARK RESERVOIR AND WELL DEVELOPMENT AREA CITY OF PALO AlTO pa207f14-6542.cdr Connection to -+J.....!' Pressure Area 1 and 3 Overflow / "-J I I I • / Connection ~ to Storm Drain Note: Facility locations and pipeline alignments are preliminary. The actual locations and dimensions (including the portions above and below grade) would be'confirmed during final site design. Supply Pipelines - -Below Ground Pipeline ~ Above Ground Structure _ Below Ground Structure ~ Restored After Construction Pump Station and Well Exhibit A-2 EL CAMINO PARK -TYPICAL RESERVOIR CONSTRUCTION LAYOUT CITY OF PALO ALTO Exhibit A-3 EL CAMINO PARK RESERVOIR, PUMP STATION, AND WELL CONSTRUCTION PLAN The proposed Emergency Water Supply and Storage Project is intended to correct the deficiency in the City's emergency water supply, when compared to the standards recommended by the Department of Health Services (DHS). Implementation of the proposed project includes the construction of a new 2.5 million gallon water storage reservoir and associated 11.5 million gallon per day pump station, a new well, and pipelines (connecting the reservoir facility to the City's distribution system) at EI Camino Park. The proposed project design is preliminary and the final project facility design would incorporate input from the public (including property owner and neighbors) received throughout the project planning and environmental review process. The final project design would be subject to review by the City of Palo Alto Architectural Review Board to ensure that project design is consistent with that of the surrounding community. El Camino Park Reservoir and Well Introduction EI Canuno Park is situated between EI Camino Real, a major thoroughfare, Alma Street, and University Avenue. The EI Camino Park reservoir site is on land leased from Stanford University, with the CalTrain Station and University A venue to the south. The northwestern portion of the park consists of soccer playfields and unimproved land, while the southeastern portion contains a parking lot and baseball field. Lytton Station is located in the northeastern portion of the park within a fenced area. The entire park is contained within a chain link fence and further screened by large, mature tress along EI Camino Real and Alma Street. Exhibit A-I identifies the potential development area at EI Camino Park. The new reservoir and well facilities could be sited in most locations of the park. A potential reservoir configuration is shown conceptually in Exhibit A-2. The proposed footprint of the reservoir is approximately 152 feet in diameter, at an excavation depth of approximately 32 feet (to maintain the bottom of the reservoir above the groundwater table per DHS requirements). The below grade reservoir would not be visible, with the exception of the associated pump station and access hatch strncture. The project siting would avoid existing mature trees located along the perimeter of the park and the northern end of the park to the extent feasible. The project would include removal and replacement of the existing Lytton Station with a new above !below ground pump station. The majority of the new pump station structure would be below grade, with the above grade portion of the pump station strncture constructed within the existing Lytton Station fenceline. Below ground pipelines connecting the reservoir facility with the pump station would be required. In addition, underground 1 070227 syn 6050102 pipelines would connect the reservoir and pump station facilities to the City's existing water distribution system. Pipeline connections could be located within the alignment of Alma Street. Construction of the reservoir, pump station and well facilities, at EI Camino Park, would not require permanent closure of the !lark to public use and no loss of parklands would occur, as the ancillary features (approximately 50 square feet) would be blended into the park features. The post- construction facility area would be approximately 0.03 acre and would be located within the existing Lytton Station fenceline. Under the proposed project, a new 2.5 million gallon reservoir and pump station, and new well facilities would be constructed at EI Camino Park to provide for emergency water supply as one component of the City's Emergency Water Supply and Storage Project. Proposed Reservoir Construction Activities The construction area required for the proposed reservoir, pump station and well facilities is approximately 4 acres. The project siting would avoid areas with identified sensitive resources to the extent possible. The site would accommodate all of the proposed structures including the 2.5 million gallon reservoir, associated pump station, well facilities, pipelines, access, and staging areas required during construction activities. Construction activities include: Site Clearing and Grading Reservoir and well construction activities would require initial site clearing and grading of up to four acres. Clearing of vegetation and trimming of existing trees would be conducted in accordance with City policies and as necessary for construction activities. New Reservoir and Associated Facilities Following site clearing, excavation of soils for installation of the reservoir would occur. Excavated soil would be stockpiled in an adjacent staging area for use as backfill material, and the remaining excavated soils would be off hauled for disposal. Vertical shoring would be installed to provide support for the reservoir excavation walls during construction. A dewatering operation would be implemented to remove groundwater during construction activities. Following excavation activities, a highly reinforced, concrete floor would be installed. Wall forms would be curved to the radius of the tank and concrete poured into the wall forms. A concrete, two-way flat slab roof would be cast in place. The contractor would then prestress the tank and apply a coat of grout using a strand wrapping machine. The reservoir would be backfilled, with approximately three feet of soil cover over the top of the structure. Reservoir Pump Station The pump station would house the well facilities, pumps, flow meters, hoist, valves, piping, standby generator, and a fuel storage tank. The pump station would consist of an above and . below grade structure. The above ground footprint of the structure would be approximately 26 foot by 44 foot, with a below ground structure footprint of approximately 44 foot by 64 foot. The exterior height would be approximately 17 to 25 feet high. The actual configuration would depend on the architectural treatments required to blend the proposed structure with the surrounding area. The facility would include access hatches, stairwells, and ventilation. The above grade structure 2 070227 syn 6050102 would be surrounded by an 8 foot high black, steel chain link fencing, with a locked entrance gate. Construction would involve excavation of the pump station area, installation of shoring materials, pouring concrete for the pump station structure (including forming, reinforcing, concrete placement and curing), and construction of above ground elements. In addition, activities include installation of pumps and motors, electrical/instrumentation, standby generator and fuel storage tank, chloramines system components, appurtenances, access stairwell and ventilation. Chloramine system components include: prefabricated storage tanks, ammonia and chlorine gas detection features, pressure relief valves with a scrubber tank to prevent discharge of ammonia and chlorine gasses, metering pumps, secondary containment to prevent any leaks (e.g. concrete containment berms), instrumentation, and controls. Well Construction The production well facilities (including pump, valves and piping, and electrical equipment) would be accommodated within the pump station structure. Well construction activities include: Drilling -The production well borehole (approximately 28 inches) would be drilled using rotary drilling methods, followed by well construction, well development, and pump· testing. The 24-hour well drilling would require portable flood lighting for nighttime construction activities. Installation ~ Following well drilling, the well casing and well screen would be installed. A sorted gravel envelope would be placed around the screen to prevent sediment from entering with the water during pumping operations. A conductor casing would be installed to a depth of around 100 feet below ground surface, to provide a concrete seal, in accordance with DRS requirements for potable water wells. Pump Testing • Following the installation of the well, a pumping test would be conducted. The test would consist of a step test lasting 8-hours, followed by a 24-hour constant rate test. The step test would be conducted to establish the performance of the well (e.g. production capacity) and to provide the required information to design the pump station facilities. A 24-hour constant rate test would be performed to develop the well and to establish the production capacity. Well Facilities and Connections· Upon establishment of a-the production well, the engineer would complete design of the well facilities including sizing the pumps, and designing the well enclosure. Connection to Existing Stormwater System. -New piping would be constructed connecting the well to the existing storm drain system. Reservoir Access Hatch and Vent Structure One 50 square foot reservoir access hatch and vent would be located on top of the reservoir. Project design would construct the access hatch to either be buried or blend in with the existing uses. 3 070227 8yn 6050102 Reservoir Pipelines New pipelines would be installed connecting the reservoir facilities to the City's existing water distribution system, as well as to connect the reservoir to the pump station. Reservoir pipelines would be approximately 18-inches in diameter. Pipeline installation activities would generally occur within public right-of-way and existing roadways, and could require temporary closure of one-lane of traffic. The City would retain a 20 foot wide permanent pipeline access easement along the pipeline route. The length of pipeline needed, and the proposed construction method (either open cut trenching or trenchless technology) would vary, based on the location of the reservoir within EI Camino Park. Pipeline construction would include: clearing and grading the right-of-way; trenching and hauling of excess spoils; relocation of utilities, if required; delivery and installation of the pipe; backfilling of the trench; filling and flushing, hydrostatic and disinfectionlbacterial testing (24 hours minimum); and restoration of the right-of-way. Lighting -Lighting at site would be dependent on the security requirements, and public input. If external lighting is required, motion sensor lighting would be installed. Site Restoration -Following completion of well construction activities, construction work areas and staging areas would be regraded, contoured, and restored to conditions and uses similar to conditions prior to construction activities, or improved with new facilities accounting for local community input. Power -Power would primarily be supplied to the well pump station via an electrical line off of an existing transformer. Access -Access to the reservoir and pump station site would be via existing roads. It is not anticipated that new access routes would be required. Construction Schedule Reservoir, pump station, well and pipeline construction activities would require approximately 24 months to complete. The overall project (including preliminary design, design and construction) would last for approximately 49 months. Construction, with the exception of the 24-hour drilling/well testing, would likely occur during weekdays from 8:00 a.m. to 5:00 p.m. Twenty- four-hour construction for the proposed reservoir, pump station and pipeline is not anticipated, but would be required for installation of the well. Anticipated Results The anticipated benefits of this rehabilitation include: .:. The ability to meet the Emergency Water Supply and Storage Project's objective to provide a supplemental water supply during "emergency" conditions through providing 11,000 gallons 4 070227 syn 6050102 per minute (gpm) of reliable well capacity and 2.5 million gallons of water storage for emergency use in Pressure Areas 1,2 and 3. Construction of facilities EI Camino Park support this objective by: );> Providing for 2.5 million gallons of water storage for emergency use in Pressure Areas 1 and 3. );> Providing for a new high production well (approximately 1,000 gpm). );> Producing chloraminated water that is compatible with the water in the distribution system. 5 070227 syn 6050102