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Show PART III FUTURE DEMANDS OBE-ERS Projections Water Supply Requirements Regional Summary A Regional summary of projected domestic, manufacturing, livestock, governmental, and commercial and other M&I water requirements for each target year is presented in Table 21. A summary of projected municipal and industrial withdrawal and depletion water requirements by states excluding livestock water requirements is presented in Table 22 for the Region. A summary of livestock water use and stock pond evaporation estimates for all target years is presented in Table 23 for the Region. As shown in Table 21, withdrawal requirements are projected to increase from 123,900 acre-feet per year in 1965 to 347,900 acre-feet per year in 2020, representing almost a two-fold increase over the study period. Withdrawals for commercial uses will be largest in 2020, with needs of 94,400 acre-feet per year. This requirement for the commercial water-use category is projected to be 50 percent greater than that pro- jected for the manufacturing water-use category in 2020. Domestic uses are the next largest category, with 88,400 acre-feet per year projected in 2020. In descending order, the next largest withdrawal requirements are for the manufacturing livestock, and governmental categories. A projected 86 percent increase in population (includes hydrologic area of Arizona), more than eight-fold increase in the value of manu- facturing output, seven-fold increase in the economic activity in the commercial category, and a rising water-use rate by the Region's Indian and rural residents are the major reasons for the growth of municipal and industrial water demands. Total water withdrawal for livestock will increase from about 35,000 acre-feet in 1965 to 59,000 acre-feet in 2020. The water consumed annually by livestock will increase from 11,000 acre-feet in 1965 to nearly 18,000 acre-feet by 2020. Increases in animal units over the study period from nearly 1 million to nearly 1.6 million account for the projected water uses. (See Table 23.) Subregions Tables 24, 25, and 26 present the projected withdrawal and depletion water requirements for the Green River, Upper Main Stem, and San Juan- Colorado Subregions, respectively. In 2020, depletions are projected to be 47,600, 61,000 and 60,500 acre-feet per year for the Green River, Upper 33 |