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BACKGROUND This project is a part of the annual maintenance program which includes replacing old water lines that have the potential to break and/or leak, including at bridge and culvert crossings. In Hacienda, there are eight locations where the waterlines cross over channels and several locations have been removed from service for repairs numerous times due to leaks. The leaks are associated with differential settlement occurring at the crossings. To address the settlement, seismic fittings are installed to accommodate the movement and protect the crossing in the event of an earthquake. Previous projects have completed the replacement of four locations; this project replaced an additional three locations. The remaining location will be replaced as a part of a future capital improvement project. This year's project also included operational improvements at Turnout 2 on the west side of Hopyard Road, north of Valley Avenue. A turnout is where the City's water distribution pipeline connects to Zone 7's water supply pipeline. Turnouts are owned and operated by the City to meter the flow of water into the City's distribution system based on demand. There are several turnouts within the city. On November 16, 2021, City Council awarded a contract for $735,777 to the lowest bidder, DPI, Inc. City Council also authorized the Director of Engineering to approve change orders up to the project contingency amount of $110,367. DISCUSSION The Annual Water Distribution System Improvement Project, CIP No. 22183, replaced three water pipeline bridge/culvert crossings — Owens Drive at Chabot Canal, Tassajara Creek on Owens Drive, and Gibraltar Drive at Chabot Canal. The project also included improvements at Turnout 2 on Hopyard Road. Each crossing consisted of removing and replacing the water pipeline spanning the crossing and adding seismic fittings at each end to connect back to the existing system. Turnout 2 was improved by adding valving and a flushing port to operate the distribution system more efficiently. The improvements were necessary due to changes in water demand since the original construction of the turnout. Construction began in February 2022 and was completed in June 2022. Four change orders were issued during construction for a total of $109,036, including $74,702 for additional work identified by City staff. The additional work under these change orders is described below. • On Owens Drive at Tassajara Creek, the limits of concrete work were increased due to additional settlement discovered after pavement removal. Moreover, the soils in the pipe excavation failed during construction and required additional shoring to maintain nearby traffic lanes. The failed trench section also required additional pavement restoration. Finally, a concrete kicker, which is used to support turns in pipelines, had to be removed and replaced to accommodate the new pipeline installation. Page 2 of 3