220 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1949 
Especially during the past century, the use of water has increased 
at an amazing rate. In 1850 only 83 cities in the United States had 
public water supplies, and only a small proportion of the homes in 
these cities had water piped directly from the city mains. By 1939 
there were 12,760 ? municipal waterworks and thousands of industries 
had private supplies from wells or surface-water sources. As the 
number of waterworks increased, the uses of water and the per- 
capita consumption also increased. The quantities of water used 
for a few purposes are given below. Flush toilets, bathing and 
laundry, street cleaning, and fire protection require an average of 
about 40 to 75 gallons per day per capita.* Processing a ton of steel 
in highly finished form requires about 65,000 gallons* of water; 
making a gallon of gasoline takes 7 to 10 gallons® of water. Vast 
quantities of water are used for air conditioning and for making paper, 
explosives, coke, textiles, and a host of other products. Thus, a large 
city, such as Chicago, with numerous industries may have a per-capita 
water consumption as high as 250 to 300 gallons per day. 
Only a few thousand acres in the West was irrigated in 1850, but 
21 million acres ® was irrigated in 1939, and many additional irrigation 
projects are under construction. An acre of cotton uses about 2.57 
acre-feet, or 800,000 gallons, of water during the growing season; an 
acre of alfalfa requires about 4 acre-feet of water; irrigation of truck 
gardens, fruits, sugarcane, rice, and other crops also requires large 
amounts of water. In eastern United States, supplemental irrigation 
is increasing because the application of a relatively small amount of 
water when it is needed by crops may double or triple the yield of 
the land. 
The greatly increased use of water has, in many places, almost fully 
utilized the readily available water supplies, drawn ground-water 
levels dangerously low, caused sea water to enter streams and ground- 
water reservoirs in coastal areas, and permitted oil-well brines or 
factory wastes to pollute many of our ground-water reservoirs and 
streams. Thus, the development of additional water supplies for 
new projects or industries has become increasingly difficult and costly. 
Nevertheless, it would be a mistake to infer that our water supplies 
are approaching exhaustion. Actually, much can be done to conserve 
and thereby increase the total amount of water available for beneficial 
use. For example, in many places spacing pumped wells over wider 
2 Engineering News-Record, vol. 123, p. 414, 1939. 
3 Turneaure, F. E., and Russell, H. L., Public water supplies, 4th ed., p. 19. John Wiley & Sons, New 
York, 1940. 
«Lloyd, Kenneth M., Industry and water supply in Ohio. Ohio State Univ. Exper. Stat. News, p. 31, 
April 1946. 
‘ Jordan, Harry E., Industrial requirements of water. Amer. Water Works Assoc. Journ., vol. 38, pp. 
65-68, 1946. 
6 Census Bureau. 
’ National Resources Committee, Regional Planning, pt. 6, p. 91, 1938. 
