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<br />1 <br />1 <br />I <br />I <br />I <br />1 <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />1 <br />I <br />I <br />1 <br />I <br /> <br />Of the three 48-inch diameter valves, that discharge water from the gate tower, one valve has <br />never been connected to an operator, one valve is not functional due to a broken stem, and the <br />remaining valve binds during operation. <br /> <br />Additionally, most of the ladders, walkways, and operator stem guides below elevation 8375 <br />inside the gate tower are no longer serviceable. <br /> <br />The Sanchez Ditch and Reservoir company is undertaking this project to continue to provide <br />irrigation water to its shareholders and to ensure the safe operation of the reservoir. <br /> <br />ALTERNATIVES EVALUATED <br /> <br />A range of alternatives were considered including 1) Don't replace any of the valves, 2) Replace <br />the six functional 3D-inch diameter wedge gate valves and repair two of the 48-inch diameter <br />outlet valves, replace all existing operators with hydraulic operators 3) Replace three of the six <br />functional 3D-inch wedge gate valves with hydraulically operated knife gate valves, repair the <br />lower two 48-inch valves replacing their mechanical operators with hydraulic operators, and <br />replace the upper 48-inch valve with a 3D-inch fixed cone valve, and 4) Abolish the existing gate <br />tower and replace with a new outlet works. <br /> <br />A subjective evaluation of the alternatives follows: <br /> <br />1. Don't replace any valves: <br /> <br />If the one existing operable 48-inch valve were to fail, there would be no control <br />of the release of water from Sanchez Reservoir. The do nothing alternative is not <br />feasible! <br /> <br />2. Replace the six fimctional 3D-inch diameter wedge gate valves and repair two of the 48- <br />inch diameter outlet valves, replace all existing operators with hydraulic operators: <br /> <br />This option would allow the company to operate at normal operating levels and meet <br />emergency drawdown requirements but provides no backup in case of hydraulic <br />system failure. Also assumes that the two 48-inch diameter valves are in suitable <br />condition to handle extended daily operations. <br /> <br />3. Replace three of the six fimctional 3D-inch wedge gate valves with hydraulically operated <br />knife gate valves, repair the lower two 48-inch valves replacing their mechanical <br />operators with hydraulic operators, and replace the upper 48-inch valve with a 3D-inch <br />fixed cone valve, construct hydraulic operating system capable of handling future remote <br />control: <br /> <br />4 <br /> <br />- <br />