Hydrology: A Question of Birthright

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Unquenchable Thirst. The consciousness comes none too soon. In the next 20 years, the world's demand for water will double. Americans, who consume 355 billion gallons a day, will raise their requirements to more than 600 billion gallons; it will be a trillion gallons by the end of the century. The statistics are less a reflection of the country's burgeoning population than the result of modern industrial society's increasing and unquenchable thirst. For all the bathtubs, dishwashers, washing machines and lawn sprinklers of an affluent era, home use of water still represents less than 10% of the nation's consumption. Nearly half goes for irrigation, another 40% for industry. It takes 770 gallons of water to refine a barrel of petroleum, up to 65,000 gallons to turn out a ton of steel, 600,000 gallons to make a ton of synthetic rubber.

Demand is so high that the search for fresh water and for the means of putting it to work economically has become an expanding challenge to scientific ingenuity. Dowsers, who used to roam the land with their unreliable witch-hazel divining rods, are no longer adequate—although there are still enough of them around to call a meeting of the American Society of Dowsers Inc. this week in Vermont. Man has taught himself to prospect for new sources of water by seismic refraction and aerial photography. Since World War II, engineers have gone into the remotest valleys to dig wells, build dams, cut canals and lay pipelines. In the U.S., some $10 billion is spent annually on dams, waterworks, sewage-treatment plants, pipelines, canals and levees.

With the pioneering Tennessee Valley Authority as a pattern, river basins all over the world are being crosshatched with dams, laced with power lines and irrigation ditches. The waters that will be backed up by Egypt's giant Aswan Dam are expected to bring forth a better life on the Ni'e. When the project is completed in 1971, Aswan Dam will put 2,400,000 acres of new land into cultivation, generate 10 billion kw-hours of electricity annually and, hopefully, double Egypt's national income. In Iraq, where water is so scarce that the penalty for maliciously damaging an irrigation works is death, plans are being made to dam the Tigris and Euphrates rivers for power and irrigation. Brazil has just completed the $186 million Furnas Dam, South America's largest hydroelectric complex. In a project financed by the U.N. and 20 Western nations, four dams are being thrown across the Mekong River and tributaries in Thailand, Cambodia, Laos and Viet Nam. As part of the Indus River project, India has built one of the world's highest dams (740 ft.) across the Sutlej River at Bhakra.

The catalogue is immense. But for all his works and all his study, man's understanding of water remains curiously limited. "Considering the forces that man is trying to affect," says Dr. Raymond L. Nace, a U.S. Government hydrologist, "we can say that he has scarcely made a dent." But scientists keep trying. Attempts at weather control, for example, have been as unsuccessful and unreliable as appeals to the rain gods of old, yet researchers continue to seed clouds with silver iodide and Dry Ice, hopeful that they may some day learn to manage what they cannot yet predict.