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Beneficial Consumptive Uses An extensive discussion of consumptive uses is treated in detail in Reclamation's "Colorado River System Consumptive Uses and Losses Report, 1981-1985." 'Ibis report is prepared jointly by the Upper and Lower Colorado Regional offices. The report presents estimates of the consumptive uses and losses from the Colorado River System for each year from 1981 through 1985. The table on the foUowing page was created using the data from the Consumptive Uses and Losses Report (June 1991). The table summarizes annual water use from the system by States, including water use supplied by ground-water overdraft. Work is now taking place to compile the 1986-1990 report. For the 1986-1990 report new techniques will be utilized to compute consumptive uses and losses. The new report will use Geographic Information Systems, Remote Sensing and Image Processing to determine irrigated acres, crop types and to compute the consumptive uses of these crops. It is expected that the 1986-1990 report will be completed in 1996. Upper Basin Uses and Losses The three largest categories of consumptive uses and losses in the Upper Colorado River Basin are agricultural uses within the basin, transbasin diversions to adjacent drainages, and evaporation losses from the major reservoirs. Estimated evaporation losses were about 825 million cubic. meters (669,tXXl acre-feet) from Upper Basin reservoirs in water year 1995. In water year 1994, 896 million cubic meters (726,500 acre-feet) were diverted for use in adjacent drainages. The total for transbasin diversions in water year 1995 has not yet been tabulated but the figure is expected to be similar to the 1994 total. Lower Basin Uses and Losses In the United States approximately 875 million cubic meters (709,000 acre-feet) were pumped for the CAP. Releases of approximately 10.1 billion cubic meters (8.2 million acre-feet) were made from Lake Mohave during water year 1995, to provide for releases to meet minimum downstream needs in the United States at Parker Dam; to supply diversion requirements of MWD and CAP, misceUaneous contractors, and other users; to offset evaporation and other transit losses between Davis and Parker dams; and to maintain the scheduled levels of Lake Havasu. During water year 1995, releases of approximately 10.8 billion cubic meters (8.8 million acre-feet) were made from Lake Mead at HOlWer Dam. These releases regulate the levels of Lake Mohave, provide for the small users on that reservoir, and provide for releases at Davis Dam to meet needs in the United States. In addition, 405.8 million cubic meters (329,000 acre-feet) were diverted from Lake Mead for use by the Lake Mead National Recreation Area; Boulder City; Basic Management, Inc.; and contractors of the Colorado River Commission of Nevada. Of the diversions from Lake Mead, approximately 236.8 million cubic meters (192,000 acre-feet) were consumptively used and the remainder returned to Lake Mead. Total releases and diversions from Lake Mead during water year 1995 were 11.3 billion cubic meters (9.10 million acre-feet). For water year 1996, a total release of 8.76 billion cubie meters (7.1 million acre-feet) from Lake Havasu is projected, including consumptive use requirements in the United States below Parker Dam, transit losses and regulation in the river between Parker Dam and the Mexican Border, and treaty deliveries to Mexico. During water year 1995, an estimated 8.21 billion cubic It is expected that MWD will divert 1.50 billion cubic meters meters (6.65 million acre-feet) of water were released from (1.20 million acre-feet) by pumping from Lake Havasu Lake Havasu (Parker Dam) to meet the requirements for during water year 1996. Similarly, the CAP is expected to _ _ water deliveries at Imperial Dam, as well as those of the _pump approxim~tely 1.27 jli)!jon cubic _Illceter~ (1.0.!!,illion Colorado River Indian Reservation near Parker, Arizona, the acre-feet). Consumptive uses by small users, river lossesor- Palo Verde Irrigation District near Blythe, California, other gains, and reservoir losses between Davis Dam and Parker miscellaneous users along the river, and transit losses Dam are projected to be a net loss of 9.9 million cubic between Parker Dam and Imperial Dam. meters (8,tXXl acre-feet). The major water diversions above Parker Dam were by the Metropolitan Water District (MWD) of Southern California and the Central Arizona Project (CAP). MWD pumped approximately 1.37 billion cubic meters (1.1 million acre- feet) from Lake Havasu during water year 1995, and . During water year 1996, diversions from Lake Mead are projected at 416.9 million cubic meters (338,000 acre.feet). Evaporation from Lake Mead is projected to be about 1.10 billion cubic meters (908,000 acre-feet) and net gain between Glen Canyon Dam and Lake Mead is expected to be about 1.01 billion cubic meters (820,tXXl acre-feet). 23