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BACKGROUND This project is a part of the annual maintenance program which includes replacing failing water lines that have the potential to break and/or leak (including at bridge and culvert crossings). Water replacement projects are selected from a list of problem areas and potential problem areas identified and maintained by the City's Utilities Division. Repair and replacement projects are prioritized based on records of maintenance, the potential for failure due to breakage, and the expected life span of the existing pipelines. Prioritization also considers the schedule of other CIP projects such as the annual roadway resurfacing projects. In recent years, the three channel crossings (Owens Drive at Chabot Canal, Owens Drive at Tassajara Creek, and Gibraltar Drive at Chabot Canal) have been removed from service numerous times due to leaks. These water lines were installed in the 1980s and provide water to the businesses within Hacienda Business Park and the residents on Owens Drive and Andrews Drive. While the water service is not completely disrupted while repairs are made as the water system is "looped," maintaining these waterlines is critical to provide the necessary quantity and quality of water to the area's customers. In the case of the City water distribution system connection at Zone 7's Turnout No. 2 located at 3400 Hopyard Road, Operations Services' Utilities Division require installation of valving and flushing ports in the piping to more efficiently operate the distribution system based upon changes in demand since the original construction. DISCUSSION This project consists of replacing the three water pipeline crossings (as described) and installing seismic fittings at each end of the new pipeline to accommodate settlement and seismic activity. On Owens Drive at Chabot Canal, 75 feet of existing pipe will be removed and replaced with new ductile iron pipe and will require trenching in the roadway. On Gibraltar Drive at Chabot Canal, 125 feet of existing pipe under the planter box alongside the westbound roadway will be abandoned in place, and new ductile iron piping will be installed within the median. On Owens Drive at Tassajara Creek, 100 feet of existing pipe under the planter box alongside the eastbound roadway will be abandoned in place, and new ductile iron piping will be installed in the roadway and require trenching. At Turnout No. 2, the work will consist of piping and valving upgrades within and adjacent to the turnout. In addition to the replacement of piping and installation of seismic fittings at the crossings, and new valves at the turn outs, the project also includes new air release valves, cathodic protection, and additional isolation valves. The improvements will allow more isolated areas to be removed from service for required inspection and maintenance, thereby reducing the number of customers affected at a time by these required operational activities. At the turnout, the improvements will allow Operations Services staff to better control how water enters the distribution system to react to changes in demand that have occurred and/or will occur over time. (See Attachment 2 for a map of locations.) Page 2 of 4