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7.2.A. - Page 1 <br /> REPORT <br /> To the Honorable Mayor and City Council <br /> From the City Manager <br /> January 12, 2015 <br /> SUBJECT <br /> Final Acceptance — Carson Reservoir Seismic Improvement Project <br /> RECOMMENDATION <br /> By motion, accept the Carson Reservoir Seismic Improvement Project, and authorize <br /> the release of bonds and the retention according to city procedures. <br /> BACKGROUND <br /> On October 10, 2011, the City Council accepted the Water System Master Plan Report <br /> and directed staff to move forward with specific recommendations for future Council <br /> consideration. As part of The Water System Master Plan, a seismic vulnerability <br /> assessment was performed to prioritize seismic improvements based on condition <br /> assessments of tanks, reservoirs and pump stations and an analysis of system pipeline <br /> performance during seismic events. The Water System Master Plan identified the <br /> Carson Reservoir as one of the most critical water facilities due to receive seismic <br /> upgrade modifications because of its age, storage capacity and ability to serve both <br /> Emerald Hills and main City during an emergency event. <br /> ANALYSIS <br /> The 3.75 million gallon concrete lined Carson Reservoir is one of two remaining <br /> underground reservoirs in the City with construction completed in 1932. The reservoir is <br /> covered with a rectangular lumber roof approximately one acre in size built in 1953. To <br /> extend the useful life, improve the seismic performance and improve the water quality of <br /> the reservoir, the project replaced the damaged lumber in the wood roof system, made <br /> structural modifications to the roof, installed water - sampling stations to monitor water <br /> quality, installed an access ladder, and replaced the inlet pipe to improve water <br /> circulation within the reservoir. Necessary repairs were also made to cracks in the liner <br /> to prevent leaking and water loss. <br /> On February 10, 2014 the City Council awarded the Contract for the Carson Reservoir <br /> Seismic Improvement project to the lowest responsible bidder, Anderson Pacific <br /> Engineering Construction Inc. of Santa Clara. Their base bid was $579,210.00 and the <br /> approval authorized the City Manager to increase the contract amount up to 10% if <br /> necessary. <br /> After the reservoir was drained and cleaned, staff performed several close up <br /> inspections of the reservoir interiors. These areas were inaccessible or were not <br />