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BACKGROUND This project is part of an ongoing maintenance program that replaces aged and problematic sewer pipelines with a potential for breakage and leaks. Sewer replacement projects are identified by the City Utilities Division and are prioritized based on past records of maintenance, potential for failure due to breakage, potential for sewer backups, expected life span of existing pipelines, and the scheduling of other Capital Improvement Program projects. The existing sewer siphon was installed in the late 1960s and provides services to a large number of Pleasanton residences west of 1-680 from Puri Court at the north, to Bernal Avenue at the south. The existing siphon has reached the end of its useful life and requires monthly maintenance to keep the siphon in operation and prevent sewer overflows. The existing line has lost capacity due to corrosion and permanent grease buildup typically seen in older sewer siphons. DISCUSSION The project installs 790 linear feet of 12-inch fusible PVC casing utilizing directional drilling. An 8-inch fusible PVC sewer main will then be pulled through the casing pipeline. The project will also install an 8-foot diameter, 15-foot deep manhole structure at each end of the new pipeline. These structures will serve as the diversions structures diverting sewage flows from the old pipeline to the new pipeline. The 12-inch casing is a requirement of Caltrans to cross under the 1-680 freeway, but is also practical as it will allow the 8-inch pipe to be removed and replaced when needed in the future at minimal cost. The project will be built from Meadowlark Park near the intersection of Regency Drive and Medallion Court (where the upstream manhole structure will be installed), and on the east edge of the Arroyo de la Laguna on the access roadway near Corte Del Mar (where the downstream manhole will be installed). The new line will run underneath the 1-680 freeway and be approximately 40 feet below the Arroyo de la Laguna. The old siphon will remain in place to be used on an emergency basis until the condition of the pipeline requires it to be fully abandoned by grout injection. Bids Sealed bids for this project were opened on April 25, 2017. Two bids were received: $1,012,900 and $1,302,500 (see Attachment 1, Bid Summary). The Engineer's Estimate for this project was $1,106,000. The low bid of $1,012,900 was received from Manito Construction, Inc. of Pleasanton, California. All bid documents were found to be in order and past work performed by this contractor was verified to be satisfactory. Staff is recommending award of the construction contract to the lowest responsible bidder Manito Construction, Inc. Budget Staff recommends that the construction contingency amount for this project be set at $100,000, approximately 10% of the construction contract. Funding and estimated expenditures are presented in Attachment 2. Page 2 of 4