OCR Text |
Show 49 full 100,000 acres which the Project was designed to serve have never been under irrigation in any one year. While irrigated acreage varies from year to year, depending upon water supply, the average annual irrigated acreage from 1934 to 1955 was 63,000 acres." The main works of the Project are Coolidge and Ashurst-Hayden Dams.78 Coolidge Dam, which is located on the Gila River below its confluence with the San Carlos River, creates the San Carlos Reservoir which has a designed capacity of 1,285,000 acre-feet. This reservoir has never been more than two-thirds full. Ashurst-Hayden Dam is 63 miles further downstream and is a purely diversionary structure serving the Project's canals. Situated within the boundaries of the Project and utilized to catch flash flood waters, excess flows from Ashurst-Hayden Dam, and to regulate canal flow is Picacho Reservoir with a capacity of 18,000 acre-feet.79 Water supply is derived from both surface and underground waters.80 From 1934 to 1955 average annual surface diversions were 187,000 acre-feet. In addition, approximately 99,000 acre-feet were pumped. Thus, about 35% of the water supply comes from ground water.81 From total supply, the farmers have received 3 to Z]/z acre-feet per acre for irrigation. The remainder is lost in transit in the canal system.82 The Gila River is the primary source of surface water, although summer floods in the San Pedro River occasionally furnish some irrigation water. Pump water comes from wells operated by the Project, 108 of which were active in 1956. Natural flow surface "Tr. 1559 (Gookin). 78See p. 39, supra. "Tr. 1492-1495 (Gookin). 80Tr. 1498 (Gookin). 81Tr. 1537 (Gookin). 82Tr. 3375-3377 (Gookin). |
Source |
Original Report: State of Arizona, complainant v. State of California, Palo Verde Irrigation District, Imperial Irrigation District, Coachella Valley County Water District, Metropolitan Water District of Southern California, City of Los Angeles, California, City of San Diego, California, and County of San Diego, California |