82 CONSERVATION OF GROUND WATER 



to meet all its obligations for diverted surface water, 

 nonirrigation-season spring flow, and developed subsurface 

 water. This surplus represented more than half the water 

 yielded by the company's wells. 



It must be concluded, therefore, that the Geneva Steel 

 Company, even with its enormous use of water, does not 

 deplete the net available supplies as much as did the same 

 property under an agricultural economy. And the best 

 prospect for development of additional water supplies in 

 the valley lies in the possibility of similarly salvaging water 

 now lost by natural processes. Such development requires 

 an adequate knowledge of the hydrology, intelligent plan- 

 ning, and wise management of the supply and its uses. 



Willcox Basin, Ariz. 25 The Willcox Basin is a closed basin 

 in southeastern Arizona. Water has been pumped from wells 

 for irrigation for 40 years, but the pumpage has been in- 

 creasing rapidly in recent years — from about 15,000 acre- 

 feet in 1946 to 28,000 in 1949. The water table has dropped 

 as much as 25 feet below its original position in some 

 pumped areas, grading to a fraction of a foot near the outer 

 limits of the basin. 



The Willcox Playa in the lowest part of the closed basin 

 discharges ground water by evapotranspiration at a rate 

 estimated to be of the order of 75,000 acre-feet a year. It is 

 not known how much of this waste could be economically 

 salvaged and converted to beneficial use. 



Tooele Valley, Utah. 26 Tooele Valley, about 30 miles 

 southwest of Salt Lake City, is bordered on the east and west 

 by mountains that rise as much as 5,000 feet above the valley 

 floor. Four small perennial streams draining these ranges 



25 Reference: Jones, R. S., and R. L. Cushman, "Geology and Ground-water 



Resources of the Willcox Basin, Cochise and Graham Coun- 

 ties, Arizona," U.S. Geol. Survey, Mimeo. rept., May 1947, 

 35 pp. 



26 Reference: Thomas, H. E., Ground Water in Tooele Valley, Utah, Utah 



State Engineer, 25th Biennial Rcpt., pp. 97-238, 1946. 



