AZ vs. CA:11 California Exhibits, Vol. XI; Nos. 1001-1011; 1101-1109; 1201-1251; 1301-13431301-1343

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-7- year period of 1928-1938 at the average rate from 1928 to 1988. The results may be summarized as follows: Development above Boulder Canyon 1928 1938 1988 Irrigated areas, acres................ 1,717,000 2,040,000 3,368,000 Capacity of irrigation reservoirs, acre-feet ...................... 662,000 ................ 2,933,000 Capacity of power reservoirs, acre-feet ................................ 10,000 ................ 8,100,000 Transmountain diversions, acre-feet annually ................ 116,000 180,000 621,000 Surface area of irrigation reservoirs, acres .................... 27,8001 \ 86,400 Surface area of power reser- 60,000 voirs, acres ............................ 2,000 \ \ 172,000 Mean depletion for irrigation consumptive use, transmountain diversions and reservoir losses, acre-feet annually ...................................... 2,760,000 3,481,000 6,595,000 Mean annual inflow to Boulder Canyon, acre-feet ................ 15,730,000 15,009,000 11,895,000 Irrigation depletion has been taken at 1.5 acre-feet per acre annually for the first one million acres of development, with all additional areas to have a normal consumptive use of 1.5 acre-feet per acre. Normal reservoir losses are assumed at 4 feet per year over the mean exposed area. These normal losses have been fluctuated for run-off conditions with departure from the normal equal to one-half the departure in the case of run-off. In estimating future stream flow, no allowance has been made for the hold-over effects of upstream storage estimated to total 11,000,000 acre-feet in capacity by 1988. Its effect would be to increase stream flow at Boulder Canyon during the critical period determining firm power capacity.