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Page 2 of 3 The existing pipeline within W. Angela Street, from First Street to Main Street, has been temporarily repaired after being damaged by utility construction and has a diameter change near Main Street. This area has seen frequent backups and pipeline failures. Replacement of this line will result in a consistent diameter of pipe and pipe material, which will improve flows. Three manholes at the intersection of California Avenue and Washington Street are currently subject to minor backups due to existing restrictions in the manhole inverts. These inverts will be reconstructed for better flows, reducing future maintenance needs. The sewer main on Arendt Way was installed before 1970, and video surveillance of the pipeline shows a major sag in the line impacting flow. This sag is causing buildup along the length of the pipe, which requires regular maintenance. Due to the age of this pipeline, a complete replacement is warranted. Continuing erosion of the banks of the Arroyo del la Laguna just south of Bernal Avenue has the potential to expose and damage the existing 18-inch sewer main in this area. To avoid potential significant sanitary sewer service interruption, this facility was placed in a new alignment away from the banks of the arroyo. The current sanitary sewer collection around Rose Avenue flows west to east and then under the Alameda County Fairgrounds. These facilities were built out as tract construction progressed westward over separate developments. As the ultimate goal was for collection to no longer require the connection under Alameda County’s property, developers were required to install a parallel system to flow in the opposite direction, exiting Rose Avenue west of Melinda Way. This project will put this system in service and abandon the previously used line. On November 15, 2022, the City Council approved a contract for $544,000 with Golden State Construction & Utility, Inc. (Golden State), a $16,800 contract with Alta Archaeological Consulting, LLC, and authorized a project contingency of $82,000 and the Director of Public Works to approve and execute change orders up to the contingent amount. DISCUSSION Golden State has relocated the 18-inch sewer line along the Arroyo del la Laguna just south of Bernal Avenue. To complete this work, additional piping was required to clear existing utility lines conflicting with the new manhole on W. Lagoon Road. Rose Avenue work is nearing completion, and flows have been redirected. West Angela Street pipe installation work has been completed and required additional work to upsize a lateral to address routine plugging due to an undersized pipe. Arendt Way work is under construction at the time of this report. Work at California Avenue is scheduled to begin in mid-December 2023. Replacement of a portion of the eight-inch sewer main within Regency Drive and under Meadowlark Park initially required removing and replacing 176 feet of pipe and installing a new manhole to facilitate future maintenance access. Following potholing, it was determined that the sag occurred under the recently renovated basketball court in Meadowlark Park and requires relocating the connection point to the north of the basketball court with the pipe then placed in an alignment to the east side of the court to the existing manhole on Regency Drive. The realignment will require an additional 220 feet of piping, an additional manhole, replacement of 400 square feet of concrete and asphalt, and the removal and replacement of six trees. The estimated cost for this additional work is $100,000. Page 221 of 270