Item 21 - Pressure Control Station Relocation and Transmission Main Improvements

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CITY OF SANTA ANA RFP NO.: 21-127 SA-2 PRESSURE CONTROL STATION RELOCATION AND TRANSMISSION MAIN IMPROVEMENTS SCOPE OF WORK Introduction and Background: The City of Santa Ana is located in the County of Orange in Southern California. The City encompasses 27.2 square miles and a population over 340,000 people. The City of Santa Ana Public Works Agency — Water Resources Division oversees and maintains the daily operations of the Water System and Sanitary Sewer System. The City of Santa Ana's water system has an average day demand of about 30 million gallons (MG) with 45,000 services. It is comprised of approximately 478 miles of water main, 45 MG of storage at five (5) sites, seven (7) Metropolitan Water District (MWD) connections, 21 groundwater wells, seven (7) pump stations, four (4) pressure regulating stations and utilizes two (2) pressure zones. The existing MWD SA-2 meter vault houses a 12-inch connection from the Metropolitan Water District's Orange County Feeder line (36-inch water main). The MWD SA-2 meter vault is currently located underneath the sidewalk on the south side of West 1 st Street, roughly 60 feet east of Bristol Street. Once outside of the meter vault, the existing 12-inch pipeline, which is cast iron and constructed in 1943, carries high-pressure water (approximately 170 psi) to an existing Pressure Reducing Station (PRS) located near the southeast corner of the intersection of Flower Street and 1st Street. The water imported from MWD exits the PRS at a lower system pressure and is deposited into Walnut Reservoir and the distribution system. The existing connection normally operates around 8.0 cubic feet per second (cfs) and has a maximum capacity of 15.0 cfs. The City of Santa Ana is requesting proposals for the purpose of providing engineering design services for the preparation of plans, specification, and cost estimate (P.S.& E.) for a new SA-2 MWD connection, 3,500 feet of transmission main with the possibility of adding approximately 2,900 feet of distribution water main. The proposed pressure control station shall be located on a City owned parcel of land located at 116 South Flower Street or 202 South Flower Street. The new station shall contain both a pressure reducing valve and a hydro -turbine generator. Power generated by the hydro -turbine generator will need to be conveyed to the Walnut Pump Station Facility by a new proposed electrical conduit. Onsite battery storage will also be required with smart programming to switch from grid power to local power on demand. The high-pressure MWD conveyance pipeline will need to be replaced from the MWD SA-2 meter vault to the proposed location of the new SA-2 pressure control station. The City also desires to attain the highest Envision Rating possible with this project. A more detailed layout of the proposed location and work shown on the attached feasibility study in Attachment 4 of the Appendix. Page 1 of 11