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<br />002813 tt . {) tt <br />~c--\v- , <br />The long-term average ~irgin)flow at lee Ferry is approximately <br />15 million acre-feet based on the 78-year period from 1906 through 1983. <br />Approximately 6.2 millon acre-feet of the water is being depleted in the <br />Lower Basin and serves to meet firm contractual water supply commitJf- <br />ments. The largest diversion, the MWD (Metropolitan Water District) <br />currently supplies southern California with approximately 800,000 acre- <br /> <br />feet annually. The CAP (Central Arizona Project), which will begin <br />operations in late 1985, will ultimately divert about 1.5 million acre- <br />feet annually. <br /> <br />, II\. t?P~ <br />C~~ <br />,.. <br /> <br />Current Upper Basin depletions are approximately 3.5 million acre-feet <br />annually. Oil shale, coal, and other future energy-related developments <br />in the Upper Basin could substantially increase water usage during the <br /> <br />next few decades. <br /> <br />Following the filling of Lake Powell in 1980, the basic operating strat- <br />egy of the Colorado River has been to maintain Lakes Powell and Mead at <br />their essentially full storage levels. Although this operating 'strategy <br /> <br />has the advantage of maximizing available water for appropriate uses, it <br /> <br />also increases flood risk during high inflow periods and reduces hydro- <br /> <br />power production flexibility. <br /> <br />The floods on the Colorado River in 1983 occurred while operations of <br /> <br />all the reservoirs were in complete harmony with the laws and regula- <br /> <br />tions which govern the operations of the river, including the "Criteria <br /> <br />for Coordinated Long-Range Operation of Colorado River Reservoirs" and <br />the flood control regulations for Lake Mead. These laws and regulations <br /> <br />3 <br />