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<br />Depletions" in table 3, Projections of water use
<br />were developed from information supplied by
<br />State water resource agencies and from
<br />construction schedules of projects authorized for
<br />construction or already under construction,
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<br />Chapter 4
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<br />Present and Future Development
<br />
<br />This section of the report summarizes the
<br />projected depletions used by Reclamation to
<br />evaluate the effects of water use and depletions,
<br />Table 3 summarizes the estimated depletion of
<br />water through the year 2010 for the main stem
<br />of the Colorado River,
<br />
<br />The projections for the years 1991 through 2010
<br />represent the best available estimate of water
<br />use over the next 20 years, The projections were
<br />made in consultation with individual States
<br />within the Colorado River Basin; however, the
<br />States do not necessarily concur with the
<br />projections adopted by Reclamation for planning
<br />purposes,
<br />
<br />Nothing in this report is intended to interpret
<br />the provisions of the Colorado River Compact
<br />(45 Stat, 1057), the Upper Colorado River Basin
<br />Compact (63 Stat, 31), the Water Treaty of 1944
<br />with the United Mexican States (Treaty Series
<br />994; 59 Stat, 1219), the decree entered by the
<br />Supreme Court ofthe United States in Arizona
<br />v, California et ai, (376 U,S, 340), the Boulder
<br />Canyon Project Act (45 Stat, 1057), the Boulder
<br />Canyon Project Adjustment Act (54 Stat, 774:
<br />43 U,S,C, 618a), the Colorado River Storage
<br />Project Act (70 Stat, 105; 43 U,S,C, 620), or the
<br />Colorado River Basin Project Act (82 Stat, 885;
<br />43 U,S,C, 1501),
<br />
<br />UPPER BASIN DEPLETIONS
<br />
<br />Table 3 summarizes estimates of future
<br />depletions due to water development in the
<br />Upper Colorado River Basin, The original
<br />depletion projections were developed from the
<br />Upper Colorado Region Comprehensive
<br />Framework Study published in 1971, The
<br />comprehensive framework study established
<br />normalized depletion levels for the 1965 level of
<br />water resource development, Updates and
<br />revisions to those tables which are not a direct
<br />result of the new projects described below are
<br />included under "Miscellaneous Additional
<br />
<br />The Upper Colorado River Basin Compact
<br />provides that the States of Arizona, Colorado,
<br />New Mexico, Utah, and Wyoming will share in
<br />the consumptive use of water available in the
<br />Upper Basin in the following proportions:
<br />Arizona, 50,000 acre-feet; Colorado,
<br />51.75 percent ofthe remainder: New Mexico,
<br />11,25 percent of the remainder; Utah,
<br />23,00 percent ofthe remainder; and Wyoming,
<br />14,00 percent of the remainder, Each Upper
<br />Basin State is charged a proportionate share of
<br />the total evaporation from Lake Powell, Aspinall
<br />Unit, and Flaming Gorge Reservoirs, This
<br />charge is provided for in Article V ofthe Upper
<br />Colorado River Compact and is identified in
<br />table 3 as "Evaporation from Storage Units,"
<br />
<br />Reclamation's most recent hydrologic
<br />determination of water available to the Upper,
<br />Colorado River Basin is 6,0 mafrather than the
<br />7,5 maf anticipated by the 1922 Colorado River
<br />Compact, While the Upper Basin States do not
<br />share Reclamation's view of water available to
<br />the Upper Basin States, they have acquiesced to
<br />Reclamation's views for planning purposes only,
<br />
<br />Arizona
<br />
<br />Miscellaneous Additional Depletions
<br />
<br />Consumptive uses due to irrigation and
<br />stockpond evaporation have increased by about
<br />5,000 acre-feet since the Comprehensive
<br />Framework Study estimates were prepared,
<br />Municipal and domestic uses have increased by
<br />about 5,000 acre-feet, The Navajo Indian Nation
<br />and the city of Page, Arizona, are expected to
<br />use additional water for municipal purposes,
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