If there is a benefit to emerge from the recent White House report on climate change, it is the growing awareness that water scarcity may be one of the most serious political and environmental challenges of our time.

The White House report, a joint scientific undertaking of 13 federal agencies, said that climate change is already affecting residential and agricultural water supplies, and that the impact of global warming is expected to become more severe in coming years. At the same time, population growth is placing increased demands on water resources. The government estimates that at least 36 states will face water shortages within five years.

As well, a recent Wall Street Journal article detailed the manner that solar power, especially in the desert southwest, is being slowed or halted by a lack of sufficient water supply.

With so much of the country at risk, what can be done about it ?

The solutions should come from the local level, rather than through a state or federally ordained system.

High priority should go to conserving water and reusing and recycling wastewater for crop irrigation. Efficient drip irrigation is far more frugal than spray or flood irrigation. Increased storage in reservoirs would help reduce the loss of rainwater due to runoff. And the replacement of aging, leaking water pipes could save billions of gallons daily.

But there is also a technology developed in the United States that could help meet the growing demand for fresh water: nuclear desalination.

For more than a half a century, U.S. nuclear submarines have used reactor-powered desalination systems to supply potable water. The reactor is attached to a desalination unit wherein heat from the reactor forces water under high pressure through membranes in a process known as reverse osmosis that separates fresh water from salty seawater.

Although most of the world’s desalination plants rely on energy from fossil fuels, several countries, including India and Japan, have plants that use nuclear energy to supply fresh water for everyday needs and crop irrigation.

Pakistan is planning to use nuclear desalination, and countries in Europe, the Middle East and South America are considering it.

Now, with growing public concern about global warming and the ramp-up in fossil fuel costs, nuclear power is gaining new support in the United States.

Nuclear plants capable of producing both electricity and heat for desalination make the most sense. Several years ago, researchers at Argonne National Laboratory determined that such reactors — known as cogeneration plants — would be more economical for desalination than plants using oil or natural gas. Given the sharp increase in fossil fuel prices in recent years, nuclear cogeneration would be an even better deal today.

Water is our most important natural resource. But we seem to have ignored the ever-increasing demand for water by assuming that supplies would always be there. That’s shortsighted. Water consumption has doubled since World War II, and projections show it’s expected to increase by 30 percent by 2050.

During last year’s severe drought in the Southeast, a political battle over dwindling water supplies broke out between Georgia, Alabama and Florida.

If we want to avoid a severe water crisis in coming years, then fundamental decisions need to be made now about conservation and increasing the supply of water with nuclear desalination. Otherwise the economic and political costs will be high.

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C.T. Carley, a native of Vicksburg, is professor emeritus of mechanical engineering at Mississippi State University. E-mail reaches him at ctcarley@bellsouth.net