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BACKGROUND This project is a part of the annual maintenance program, which includes the replacement of failing water pipelines. Water pipeline replacement projects are selected from a list of problem areas or potential problem areas identified and maintained by the City's Utilities Division. Repair and replacement projects are prioritized based on maintenance records, failure potential, damage caused by breakage, and the expected life span of the existing pipelines. On May 2, 2023, the City Council awarded the annual maintenance project to DPI, Inc. for $334,084 and authorized staff to approve and execute contract change order(s) for a not-to-exceed project contingency amount of$50,000. DISCUSSION To ensure the delivery of water purchased from Zone 7 Water Agency, interim water improvements to increase water supply through existing turnouts are presently under design. Interim Water System Improvements Modeling Temporary water improvements were modeled and identified that a 12-inch water line at Turnout 1 (located at Santa Rita Road and the Iron Horse Trail) should be put back in service as the water line was out of service due to a leak, and the turnout was shut down due to flood damage to the equipment. Turnout 1 is a redundant turnout and not needed when the wells are in service. In spring 2023, Turnout 1 was repaired and returned to service; this repair of the 12-inch line allowed for increased turnout capacity and improved the water system's balance. The modeling also identified the need to increase the firm capacity of Turnout 4, located at Stoneridge Drive and Hopyard Road. A turnout's firm accommodation includes adequate pumping equipment and/or treatment capacity to meet peak daily demand. The pressure that pushes the water from Zone 7's line to the City's distribution system drops during peak demand periods, reducing the amount of water the City can receive. Zone 7 informed the City that Zone 7 could not increase the pressure of its supply line and that the City would need to install a booster station; a permanent booster station is now being designed for the interim water improvements. It is recommended that a temporary booster pump be installed at Turnout 4 that can be used to meet peak demand periods without utilizing the wells until the permanent station is built. To install a temporary pump, underground piping improvements are needed to connect the pump to the system, which includes installing a suction and discharge line onto the existing discharge line at Turnout 4, relocating the fluoride injection vault, and building a pad for the temporary pump. In addition, two isolation valves on the water line in Santa Rita Road are broken and need to be repaired. Interim Water System Improvements Project Progress Santa Rita Road at Turnout 1 The contractor located and repaired the leak on the existing 12-inch water main. The work was complicated by a Kinder Morgan gas line and a PG&E gas transmission line Page 2 of 4