Our diminishing water

There's a story in Texas about the rancher who complained when a well driller found oil instead of the water he had been sent to look for. "Cattle can't drink that stuff!" the rancher cried.

That story is no longer funny. We are short of both oil and water, but the water shortage is worse. We cannot live without oil in the style to which we have become accustomed, but we cannot live at all without water. And we are using water a great deal faster than it is being replaced. The replacement rate is dependent on rainfall (sometimes in the form of snow) to resupply rivers, lakes, and ground water. A century ago, a drought affected only farmers and perhaps inland navigation; now it affects everybody. Worse, droughts are occurring more frequently and are increasing in severity, not only in the United States but also abroad.

Even without droughts, rainfall is insufficient to maintain a balance. Rivers are running dry, especially in the West. Earlier this spring, the Rio Grande, the primary water source for both sides of the US-Mexican border between El Paso and the Gulf of Mexico, simply stopped dry 50 feet from its mouth. The Ogallala Aquifer, a huge natural underground reservoir stretching from Texas to South Dakota, was an estimated 100 meters thick when settlers arrived on the Great Plains in the 19th century. An estimated 60 percent has already been extracted. What's left is becoming more expensive to get out, but is being removed at an increasing rate regardless of cost. In 1997, 6.2 million acre-feet were pumped; nature resupplied 439,000 acre-feet. This is a depletion rate of 93 percent.

So much water has been taken from the Colorado River by Arizona and California that Mexico has complained that those states have exceeded the US share under a 1944 treaty on water-sharing. Southern Californians also have elaborate arrangements to transport water from the Pacific Northwest, which has it in abundance, to the their area, which doesn't have nearly enough to support its population. The Northwest is showing signs of getting tired of this drain.

Nor is the US the only country short of water and getting shorter. The Sahara is spreading south as the people who live there overgraze and overcultivate the land. (Parts of the US West are subject to the same degradation.) At one time when the oil-producing Middle East was awash in money, there was a serious suggestion that Antarctic icebergs be wrapped in plastic and towed to Saudi Arabia.

Short of such a fanciful solution, the US has two broad options, neither palatable. We can conserve or we can produce. The former is inconvenient or worse: less irrigation (and thus less food), fewer swimming pools, golf courses, and green lawns. The latter is expensive: desalinization of sea water. In the quantities necessary, this would probably require nuclear power. It is technically feasible, but expensive, and was considered 30 years ago as a joint US-Mexican project in the Gulf of California to alleviate the Colorado River problem. As more of it is done, the cost could be expected to come down; and as we became more desperate for water, we would be more willing to pay the cost even if it didn't come down.

A solution currently being advanced in west Texas is a concept called "water ranching." This is an arrangement whereby large landowners would sell the groundwater under their land, for whatever the market would bear, to cities that might be hundreds of miles distant. This would involve the considerable cost of pipeline or aqueduct construction and would mean faster depletion of groundwater reserves. It would also mean less food production. Some ranchers are talking about getting out of agriculture entirely and devoting themselves to peddling urban water supplies. This might be good for the land, but not for dinner tables.

It's a good bet that during the 21st century some new arrangements are going to have to be made about the nation's - and the world's - water supplies. These are likely to be neither cheap nor easy. They are more likely to be cheaper and easier if we have thought about them in advance. It is not too soon to begin. We have been used to choices of guns or butter. This one might be water or meat.

Pat M. Holt is former chief of staff of the Senate Foreign Relations Committee.