National Geographic : 1952 Aug
Water for the World's Growing Needs Ever Seeking More, Man Makes Better Use of Earth's Liquid Assets, Fights River Pollution, Even Desalts the Sea BY HERBERT B. NICHOLS AND F. BARROWS COLTON WHEN drought hangs hot over the land, when fields parch and wells run dry, men in many parts of the world, in their seasons, look to the sky and pray for water-maya, shui, pani in Arabic, Chinese, Hindustani. Yet within the same year runaway rivers like the Mississippi and Yangtze spread muck, death, and destruction over hundreds of square miles. How to make best use of the rain that falls is one of man's oldest and greatest problems, for without the bounty of the clouds life on earth would not last long. Our very bodies are about two-thirds to seven-tenths water. A man can live some 30 days without food, but no more than a week without water. Americans Use 1,100 Gallons a Day New York City authorities watch daily rain fall reports with new interest since their wryly remembered water shortage of 1949-50. Ac tually, they suffered only minor inconvenience - fewer baths and shaves, no washing cars and sprinkling lawns, using paper cups at fountains instead of drinking from spouts, and washing all the day's dishes at once. But these small annoyances drove home a telling fact: even in a great modern city you can't take water for granted. Nowadays we hear much about dropping water tables, artificial rain making, the urgent need of finding a way to make the ocean drink able. Yet actually, for the earth as a whole, we have as much water as we ever had. Though rainfall varies from year to year, there is no sign of any permanent decrease. Rainfall in the United States has averaged 30 inches a year ever since 1870 when Gov ernment agencies started keeping records. Every year, as rain, snow, or hail, 10 mil lion gallons fall for every man, woman, and child in the country-surely enough to go around. Then why these water shortages? One difficulty is that the water is not evenly distributed. In many local areas the demand is exceeding the present supply. Sites for our industrial and population centers were not often chosen with an eye to long-range water needs. But another important part of the answer is the fact that world population is growing now placed at about 2,400,000,000-and that many millions are using more water than ever. The average American uses far more water than his grandfather. Bathtubs, sinks, and running water are considered essentials rather than luxuries. Electric washing machines, automatic dishwashers, garbage-disposal units, all require more than the old-fashioned equip ment they replace. In Washington, D. C., air-conditioning plants are estimated to ac count for 15 to 20 percent of the water now used. Though our average citizen drinks less than half a gallon of liquid a day, he uses about 1,100 gallons of water daily for all domestic, agricultural, and industrial purposes, not counting hydro power. In just the last ten years use of water in the United States has jumped from 150 billion gallons a day to more than 170 billion. In Texas the population nearly tripled in the 50-year period ending in 1940, but use of water increased 71 times on an average for all pur poses. For industries and municipalities the increase was 30 times: for irrigation, about 55 times; for water power, about 85 times. Vast Quantities Needed by Industry Few people realize that today water is the largest single raw material used by American factories. We could not make cars or tele vision sets without plenty of water. For example, it takes 65,000 gallons, or 270 tons, of water to produce one ton of highly finished steel. Chiefly for cooling and quench ing and granulating slag, American iron and steel mills use nearly five times as much water in an average day as all of New York City. To make a ton of the high-grade paper used in this Magazine takes 70,000 gallons, to wash away impurities and assist the refining process. Other industries use vast amounts for cool ing, removing impurities, preparing solutions, and diluting and removing wastes, besides using water as an ingredient of finished prod ucts. Many industries, including steel plants, oil refineries, and chemical factories, circulate used water through cooling towers and re-use the same water as often as ten times. In the last 100 years, population of the United States has increased more than 600 per cent-which means six times as many users for the same amount of water. Most of this great growth of population has been in the large cities. Half of the people of the United States now live on less than two percent of its land area.