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BACKGROUND <br /> The City has encountered water quality problems at the Foothill Reservoir that have <br /> caused the tank to be taken out of service and drained on a regular basis. The <br /> configuration of the tank piping allowed layering of the water in the tank which <br /> prevented appropriate water turn over. In addition, the piping coating system in the tank <br /> was failing and corrosion of the pipe contributed to the water quality issues. <br /> On December 6, 2011, City Council approved the construction contract to Trinet <br /> Construction Inc. in the amount of $210,670. The project removed the existing outlet <br /> piping, extended the existing inlet piping, recoated the metal surfaces, and installed new <br /> roof vents. The project has since been completed and is ready for acceptance. <br /> DISCUSSION <br /> This project is part of the City's on-going maintenance program to improve the water <br /> quality and reduce long-term operation and maintenance costs. The project enhanced <br /> the inlet piping, thereby improving the mixing in the tank. <br /> There were six construction change orders issued for the project resulting in a net <br /> increase of $37,886, approximately 18% of the original contract. Major change orders <br /> included: the repair/replacement of portions of the asphalt driveway around the tank <br /> because of failure of the pavement, modifications to the roof vents, installation of new <br /> hardware on existing hatches, and spot repair of the coating system. <br /> When the tank was placed back in service in Spring 2012, paint failure was observed <br /> within weeks. The tank could not be taken out of service until the following fall when <br /> water demand is lower. Once the coating system was inspected, all parties agreed upon <br /> the repair method, but there was disagreement regarding the cause of failure. After <br /> much discussion, the spot repairs costs were split with the contractor and the City, each <br /> paying $8,998. In addition, the closure of the project was delayed by the subcontractor <br /> associated with the completion of the punch list items on the roof vents. The contractor <br /> hired another subcontractor to complete the work. <br /> Total project expenditures are $264,011 (see Attachment 1 for the Funding and <br /> Expenditure Summary). A total project balance of $26,300 is remaining and staff <br /> recommends the balance be returned to the Water Replacement and Improvement <br /> Fund balance. <br /> Page 2 of 3 <br />