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It is technically possible to screen river diversions with screens with extremely small openings; <br />however, as screen size decreases, both construction and operational costs increase. Therefore, it <br />is the desire of the program to determine the largest screen size that would balance loss of fish <br />with costs. <br />While this EA does not fully consider the possible construction of upstream passageways at the <br />Price-Stubb Dam and Government Highline Canal Diversion, the Service and Recovery Program <br />concur that if fish screens are needed at these facilities in the future, the funding and operation <br />and maintenance would be the responsibility of the Service and/or Recovery Program. Similarly, <br />loss of endangered fish at these structures would be handled the same as at the GVIC Diversion <br />Dam. This "incidental take" is discussed elsewhere in the EA. <br />Alternatives Discarded <br />Several alternatives were considered but dismissed for several reasons. One alternative was to <br />remove the GVIC Diversion Dam and install a pump to provide water to the GVIC Canal. To <br />ensure the 640 cfs water right, it was apparent that the present gravity-flow system was more <br />reliable than a pump would be. The pump installation would be costly to construct and would <br />have high annual maintenance and operation costs. In addition, pump failures could have <br />significant adverse economic costs to farmers and other water users. <br />Another alternative, considered but dismissed, was related to streamflow management. <br />Streamflows could be kept at an elevation that would allow the endangered fishes to pass the <br />GVIC Diversion during even normally low water periods. Since the GVIC Diversion becomes <br />passable at streamflows of 12,000 cfs and the river flow is often in the 2,000 to 4,000 cfs range in <br />the summer and fall, the amount of water needed was considered excessive and would interfere <br />with existing and future water users. <br />13