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BACKGROUND This project is part of the annual maintenance program, which includes replacement or rehabilitation of sewer pipelines and structures. Sewer replacement and rehabilitation projects are selected from a list of problem areas or potential problem areas identified and maintained by the City's Public Works Department, Utilities Division. Projects are prioritized based on maintenance records, the potential for failure or damage caused by breakage, and the expected life span of the existing pipelines. Attachment 3 shows the project locations. Video surveillance of the existing 8-inch sewer main under Meadowlark Park reveals a substantial sag, impacting flow and causing consistent buildup along the length of the pipe. This line is currently hydro-jetted clear on a monthly basis. Replacement of the main from Regency Drive to a new manhole near the park's existing basketball court will remove this problem and reduce maintenance needs. The existing pipeline within W. Angela Street, running 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 prior to 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 will be placed in a new alignment away from the banks of the Arroyo. Current sanitary sewer collection around Rose Avenue flows from 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. DISCUSSION Replacement of a portion of the 8-inch sewer main within Regency Drive and under Meadowlark Park will require removing and replacing 176 feet of pipe and installing a new manhole to facilitate future maintenance access. Page 3of5