| OCR Text |
Show - 15 - treated in this report. The values for the individual basins are shown in the table below. Volume of Reservoir Depth of Specific available water area reservoir yield in storage Basin (acres) (feet) (percent) (acre-feet) 1. Salt River Valley 1,600,000 100 12 19,200,000 2. Lower Santa Cruz 1,500,000 100 10 15,000,000 3. Avra-Altar 540,000 100 8 4,320,000 4. UTpper Santa Cruz 570,000 100 10 5,700,000 5. Upper San Pedro 535,000 100 6 3,210,000 f>. Lower San Pedro 370,000 100 6 2,220,000 7. L'pper San Simon 640,000 100 6 3,840,000 S. Lower San Simon- Gila River 735,000 100 8 5,880,000 9. Duncan 175,000 100 8 1,400,000 Question IV. What is your Department's estimate of the safe yield in acre-feet of all the underground reservoirs of this basin? Question V. For the last 10 years of record give in acre-feet the average annual surplus or overdraft for the South Coastal Basin. The estimate of the safe yield of all the basins in Arizona and the average annual surplus or overdraft are interrelated and are discussed together. Estimates of safe annual yield are made only for Basins 1, 2, 3, and 4 and are tabulated below. The determination of safe annual yield of the Salt River Valley (Basin 1, pi. 1) is complicated by the large, and yet undetermined, volume of water that must be allowed to flow out of the basin in order to maintain the salt balance. Consequently, the estimate of safe annual yield for Basin 1 is stated as being between probable upper and lower limits. |
