65. Has an efficient method of obtaining fresh water from sea 

 water been invented? 



Compared to the cost of purifying fresh water, desalinization is not 

 yet an efficient method of obtaining water for either drinking or irriga- 

 tion. Only in a few water-poor areas is it now economical to desalinate 

 sea water. As commercially practical plants reduce water costs, the con- 

 sumption of water will increase, making the desalinization operation not 

 only attractive but also essential. 



Use of water in the United States is increasing at the rate of 1.5 mil- 

 lion gallons an hour! In many parts of the country water shortages are 



already critical. Recognizing this crisis, the U. S. Congress in 1952 passed 

 the Saline Water Act; this Act established the Office of Saline Water and 

 assigned to it the primary mission of developing practical low cost com- 

 mercial ways to increase the supply of potable water. Using the best com- 

 mercial methods available in 1 952, the cost of producing 1 ,000 gallons of 

 fresh water from sea water was more than 4 dollars. Today the cost is 

 about 1 dollar; future cost of 20 to 30 cents per 1,000 gallons is con- 

 sidered entirely possible. 



A nuclear powered plant is scheduled to begin operation in southern 

 California in 1972. Capacity will be 150 million gallons per day plus 

 1,800 megawatts of electricity. This one plant will produce more fresh 

 water than all the desalination plants operating throughout the world in 

 1966. 



There are a number of desalinization methods. Freezing of sea water 

 leaves about one-third of the salts in pockets in the ice. Use of semi- 

 permeable membranes, ion exchange, and salt-eating bacteria has been 

 considered experimentally. Scripps Institution of Oceanography is 



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