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<br />3& <br /> <br />occurs. <br /> <br />Meeting five of the Commission contained the most e;,tensive discussion <br /> <br />of this provision for a pool of reservoirs. Mr. Larson, a regional director <br /> <br />from Utah, discussed three possible plans for operating a pool of main stem <br />reservoirs along the Colorado. The first plan would entail building a series <br />of reservoirs uith a very large holdover capacity, perhaps as high as 35 million <br />acre-feet. In a uet cycle such as that of J.922-1929, there l<Quld be enough cap- <br />acity "to store every drop that l{Quld not have to be released belOll Lee Ferry." <br /> <br />This idea of reaching the ma;dmum holdover storage, hOl;ever, would have to make <br /> <br />provisions for the high evaporation rates on reservoirs with an extensive <br /> <br />surface area. The Final Engineering Report, using tI,e total storage capacity <br /> <br />figure of 34, 500,000 <br /> <br />acre-feet estimatE'd tllat the \{ater depletion <br />131 <br />\{ould amount to abcut 481,000 acre-feet. <br /> <br />due to such <br /> <br />reservoir evaporation <br /> <br />The second <br /> <br />plan that Larson described \{ould entail reducing holuover storage in order to <br /> <br />reduce high evaporation losses. In very wet years some water would be spilled <br /> <br />because these smaller reservoirs l{Quld not have the ca'lJacity to hold all of it. <br />Larson appeared to say this spilled water would be delivered to help exceed the <br />7.5 million goal for that \>let year. In subsequent dry years, then. the armual <br />deliveries to the Lower basin could then be reduced to average out the ten-year <br />delivery at 75 million acre-feet as reSuired by the Colorado River Compact. The <br />third plan, which Larson quickly dismissed, involved cutting down reservoir <br />holdover even more to save costs of construction, operation, and evaporation <br /> <br />losses. Yet the amount of water that would be spilled, according to Larson, <br /> <br />would be "more in the wet cycle than I,e can recover." HE recommended to the <br /> <br />Commission a large holdover capacity in most of these main stem reservoirs because <br /> <br />of several unknowns, most importantly the occurance and potential severity of <br />132 <br />drought cycles. <br />