268 CONSERVATION OF GROUND WATER 



tion practices are far from universal. Apart from the question 

 of cost, there are many areas, of course, where some conserva- 

 tion measures are not justified because supplies are still suffi- 

 ciently abundant. 



Temporary water shortages in various areas have shown 

 that much water can be saved by economy in use. In New York 

 City the usage of water was cut 25 per cent in late 1949 by 

 such measures as repairing leaky pipes and fixtures, turning 

 off faucets when not needed, and other economy measures, 

 some of which caused hardships to certain water users and 

 were enforced only for the period of emergency. Many of 

 these economies, however, are habitually practiced in places 

 where water is perennially in short supply. For example, there 

 are statutes in many western states prohibiting Avaste of water 

 from flowing wells. In most of these states beneficial use is the 

 basis of all water rights. Nevertheless, even in the most arid 

 states there are opportunities for further conservation of 

 water merely by economy in use. Efficient techniques in irri- 

 gation can conserve water and also prevent waterlogging and 

 leaching of soils; but in many places such techniques are still 

 not the rule. Many industrial plants have achieved great 

 economies in use of water, and thus have demonstrated the 

 possibilities of water conservation by industrial users where 

 necessary. 



Similarly, there is a wide variety of conservation practices 

 that maintain the quality of water. Some prevent natural 

 waters from contaminating usable supplies, for instance, the 

 construction of wells to prevent entry of brines, or the pond- 

 ing of brine springs to prevent their flow into streams. In 

 ground-water reservoirs where there is danger of salt-water 

 intrusion, pumping may be limited to protect the supply. In 

 general, preventing or controlling pollution in lakes, streams, 

 and coastal waters maintains the usefulness of these water 

 sources, not only for our needs but for fish and wildlife. 



Storing water in reservoirs when there are surpluses from 

 precipitation is, of course, generally practiced. Arguments 

 have developed, however, as to the relative merits of the vari- 



