If there is an essential resource that surpasses energy and is requisite to sustain life, it is water — potable, abundant, inexpensive water for industry, commerce, homes, agriculture, recreation and even energy production. Yet after a decade of drought afflicting the Southwest and growing concern over global warming, little attention is given to a technology that could alleviate and even eliminate these water shortages. That technology is nuclear desalination.

The idea of using nuclear energy to desalinate seawater is not a pipe dream. Indeed, nuclear reactors on U.S. submarines have used nuclear-generated heat to provide potable water for the crews and steam generation for propulsion ever since the USS Nautilus was launched more than a half-century ago. Japan, India and other countries use nuclear desalination to provide fresh water for industry and farming and culinary needs. Many Middle East countries are now examining this technology.

Water desalination is safe and simple. Nuclear energy supplies heat for a simple passive process that produces potable water from brackish or salty water. Known as reverse osmosis, desalination is a proven technology that could supply water throughout the Southwest from seawater, degraded surface waters and brackish groundwater. Even the Great Salt Lake and Utah Lake could serve as sources for potable water.

Improved water management supported by conservation methods is needed to preserve all water resources. Wastewater should be recycled for irrigation and watersheds improved and expanded. But these measures are not sufficient, and desalination using nuclear energy is a vital part of the solution.

Of course, other energy sources can be used to supply heat for desalination. But as oil and natural gas costs escalate, nuclear power costs have decreased. Nuclear-generated electricity is less than a quarter of the fuel costs for plants burning oil or natural gas, and nuclear produces no greenhouse gases.

The U.S. Department of Energy should promote the use of nuclear reactors for desalination. A good start would be to build a small pilot reactor coupled with a desalination system that also produces electricity. Such a demonstration cogeneration plant could supply potable water without greenhouse-gas emissions and prove more economical than fossil fuels and renewables, according to Argonne National Laboratory.

If we fail to secure adequate water for the Southwest, our entire economy and standard of living will be at risk. We need a dual-purpose reactor, linked to a desalination system, to demonstrate the reliable production of electricity and fresh water. Instead of unfounded fears over the safety of nuclear power and management of nuclear wastes, public leaders in the Southwest must recognize the seriousness of water shortages and lead the effort to ensure adequate supplies of life's elixir — water.

Gary M Sandquist is a professor emeritus at the

University of Utah.