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Page 2 of 4 that a pre-packaged pump station would increase the system's reliability and reduce the staff time necessary to operate and maintain the modified underdrain system. Also, after cleaning and reinspecting the park’s storm drain outfalls, two additional outfalls were identified as needing repairs. On February 1, 2022, the City Council authorized a task authorization amendment for an additional $36,915 to complete the design and prepare biddable construction documents, increasing the total task amount from $74,480 to $111,395. On January 17, 2023, the City Council awarded the subject project to Golden Bay Construction, Inc. for $1,561,960 and authorized staff to approve and execute project change order(s) for a not-to-exceed project contingency amount of $235,000 (approximately 15 percent), for unforeseen yet necessary related work. DISCUSSION The designed system diverts recycled irrigation water collected in the underdrain system to the sanitary sewer for treatment at the DSRSD plant as required by the State Water Board. The system design includes valves that will allow the underdrain system to discharge to the storm drain system during the wet weather season when the irrigation system is disabled. This valving will avoid the expense of unnecessarily sending stormwater to the DSRSD plant for treatment. The work included the installation of 1,500 linear feet of new eight-inch gravity flow recycled water pipe by open trench and horizontal directional drill operations, 14 new manhole structures, two recycled water package pump stations with electrical and controls systems, and 600 linear feet of new two-and-a-half-inch PVC recycled water force mains by open trench. The project also rehabilitated four concrete storm drain outfalls, including 570 linear feet of existing 18- to 48-inch-diameter corrugated metal storm drainpipe using a cured-in-place pipe liner. During construction, there was minimal impact on the Val Vista Community Park’s daily field usage. The park was open to the public during construction and the 2023 sports tournament season. DSRSD assessed a one-time capacity charge in the amount of $17,367 for diverting the park’s soccer field underdrain recycled water to the sanitary sewer system. The fee was required for the generation of additional flow and treatment of BOD (Biochemical Oxygen Demand) and SS (Suspended Solids). Annual sewer fees, currently in the amount of $525, will be added to the sewer billing account of Val Vista Park’s concession building for generating extra wastewater flow into the sanitary sewer networks. The annual rates, which include local Pleasanton sewer and regional DSRSD fees, are based on the assumed flow of 220 gallons per day or the equivalent of one dwelling unit. The City's on-call vendor performed miscellaneous park drainage improvements, including the placement of cobblestone around inlets to prevent larger pieces of bark and mulch from entering the drainage system and the installation of a chain-link fence to enclose the pump control panels securely. The project greatly reduced the efforts required to store and pump the recycled water as the old manual operation was very labor-intensive and required continuous monitoring. Page 44 of 554