OCR Text |
Show -3- 504,000 acre-feet at source if all of the area were converted to uses other than agricultural. In a report entitled "Economic Survey of Salt River Project, Arizona", dated September, 1942, Mr. Raymond A. Hill, Consulting Engineer of the firm Leeds, Hill, Barnard and Jewett stated that, based on records of flow dating back to 1889, the present storage capacity on the Salt River would make it possible to regulate the flow of that river below Stewart Mountain Dam to provide not less than 700,000 acre-feet each year for Project uses. With Bartlett and Horseshoe Dams available to control the flow on the Verde River which joins the Salt River just above the point of diversion, water from the Verde River is also available to the Project. In the 14 years of record since 1941, the minimum release of water on the Verde for downstream use was 185,331 acre-feet. The future minimum annual supply from both rivers may be assumed as 885,000 acre-feet. It appears, therefore, that the available surface water supplies of the Project, without pumping any ground-water, would be adequate to supply an area of 100,000 acres devoted to urban development (210,000 acre-feet per year), and still have ample water for agricultural use on the remaining 140,000 acres of Project land (140,-000x4.7 = 658,000 acre-feet per year). Thus even if lowering of the groundwater level continues to the point where it would be uneconomical to obtain any water from that source, the surface supply available to the Project would still be adequate to serve cities and towns covering twice the Project land now so occupied while maintaining a full agricultural economy on the remaining land. If the urban development in the Valley should expand suffi- |