92 CONSERVATION OF GROUND WATER 

 PROBLEMS OF MAXIMUM SUSTAINED DEVELOPMENT 



It is evident that the arid regions have ground-water res- 

 ervoirs in almost every stage of development, from those 

 practically unused and capable of considerable development 

 to those capable of very little sustained perennial use and 

 seriously overdeveloped. Many reservoirs are in areas where 

 the land and other resources are eminently suitable for the 

 enterprises of civilization, and those enterprises are limited 

 only by the amount of water that can be made available 

 perennially for their use. Eventually, every ground-water res- 

 ervoir in the arid regions will doubtless be scrutinized to 

 determine its capabilities in this respect, although attention 

 to date has been concentrated on those areas where needs have 

 been most urgent. A fundamental requirement for a satis- 

 factory answer to this question is a knowledge of the locations 

 and rates of replenishment and discharge over a sufficiently 

 long period of time. With this information, comprehensive 

 development for maximum utilization of the resource is pos- 

 sible. Enid, Okla., provides an example of full development of 

 a ground-water reservoir where the limited potentialities of 

 that reservoir have been recognized. 



Enid, Okla. 33 This city obtains its water from a ground- 

 water reservoir in terrace sands and gravels north of the 

 town. The terrace has an areal extent of 50 square miles, 

 and under somewhat less than half that area the water- 

 bearing materials are thick enough to yield water for muni- 

 cipal supply. The reservoir is replenished entirely by 

 precipitation on the terrace. Experience has shown that the 

 replenishment is enough to furnish about 2 million gallons 

 a day and that this quantity can be obtained satisfactorily 

 from wells spaced about half a mile apart. The requirements 

 of the city have passed this limit, and Enid is planning to 

 develop additional supplies, not by sinking more wells in 

 the fully developed reservoir but by tapping other sources. 



S3 Reference: Schoff, S. L., "Ground-water Conditions in the Vicinity of 

 Enid, Okla.," U.S. Geol. Survey, Mimeo. rept., 1949. 



