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BACKGROUND The subject project is located at two sites, Kilkare Road, and the southern end of Pleasanton Ridge Regional Park within the East Bay Regional Park District (see Attachment 1). The Kilkare Road project site will consist of replacing three sub standard pressure reducing stations, fourteen main line valves and nine blow -off assemblies. The Pleasanton Ridge project site will consist of replacing one pressure reducing station and one sub standard fire hydrant. This water system (also referred to as Assessment District No. 1) was built in the early 1960's to serve the Foothill Road Corridor, and Kilkare Road Canyon. The water system consists of seven water tanks on the Pleasanton Ridge, adjacent to Foothill Road. The water discharges from the water tanks into 12" water mains along Foothill Road, Pleasanton Ridge and Kilkare Road. In order to control the water pressure (caused by the elevation difference between the water tanks and the points of service) from exceeding deliverable water pressure (between 45 -60 pounds per square inch) to the residents, pressure reducing stations are required at specific locations to reduce the water pressure from the Pleasanton Ridge water tanks to Kilkare Road and Foothill Road residents. The water pressure entering a pressure reducing station can be as high as 110 pound per square inch (psi) and must be reduced to 60 psi in order to serve the residential homes without damaging their plumbing fixtures. The existing pressure reducing stations and main line valves within this system are reaching the end of their useful life and replacement parts are hard to find. In addition to replacing the valves, interior piping within the pressure reducing stations will be increased to meet additional fire flow demands. The concrete vault enclosures which house the pressure reducing stations will be replaced to handle the increased interior piping sizing and to secure the facility. Included with this project are the replacement of main line valves to ensure successful operational shut downs when necessary, and installation of blow -off assemblies for proper purging of the accumulated sediments in the main line to maintain the overall quality of the water system serving approximately 147 residents on Kilkare Road. DISCUSSION Bids Sealed bids for this project were opened on Thursday, July 23, 2009. There was a total of ten bids received ranging from $358,675 to $554,661, compared with the engineer's estimate of $320,000 for the project (see attached Bid Summary). The low bid of $358,675 was received from William G. McCullough Company of Antioch, California. Since 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 this firm. Budget Staff recommends that the construction contingency amount for this project be increased from the usual 10% to 15% due to the potential for encountering unstable Page 2 of 3