AZ vs. CA:01 California Exhibits, Vol I, Nos. 1-57

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-13- plants at Bridge Canyon, Hoover Dam, Davis Dam, and Parker Dam. Under this plan of operation the latter three plants receive a credit of power output equal to their production without Bridge Canyon. The remainder of the firm energy output of the system is credited to Bridge Canyon. On the basis of these operation studies, it is estimated by the Department that the annual firm power production of the Bridge Canyon power plant would be 3.5 billion kilowatt-hours under initial conditions of operation. As outlined in the answer to question 12, which is based upon the premise that neither Bluff Dam nor Glen Canyon would be in operation, Bridge Canyon Reservoir would be substantially filled with silt within 35 to 45 years. Bridge Canyon power plant would of necessity be operated thereafter as a run-of-the-river plant. So operated the firm output is estimated to be about 3 billion kilowatt-hours annually. 14. Question. What is the estimated cost of the upstream storage, if any is necessary to assure production of firm power at the Bridge Canyon Dam and power plant in the annual amounts estimated in House Document 136, Eighty-first Congress, first session? Answer. The Bureau of Reclamation report on the central Arizona project proposed construction of Bluff Dam on the San Juan River and Coconino Dam on the Little Colorado River as adjuncts to Bridge Canyon Dam. Bluff Reservoir would have served to retain sediment which would otherwise deposit in Bridge Canyon Reservoir, to provide river regulation, and to control floods. Coconino Reservoir would serve to keep the sediment load of the Little Colorado River out of Bridge Canyon Reservoir, and to provide flood control. On the basis of a total