The Last Drops

By EUGENE LINDEN

Swaminathan Asokan dreams of water. It gushes out of a giant tap and fills bucket after bucket. But then he wakes up -- to a nightmare. For at Asokan's house in Madras, India's fourth largest city, there is no water. The tap has long been dry. So he must get up in the dark of night and, laden with plastic pails, take a five-minute walk down the street to a public tap. Since the water flows only between 4 a.m. and 6 a.m., Asokan, 34, a white-collar worker at a finance company, tries to be there by 3:30 a.m. to get a good place in line. His reward: five buckets that must last the entire day.

Compared with many of his countrymen, Asokan is fortunate. At least 8,000 Indian villages have no local water supply at all. Their residents must hike long distances to the nearest well or river. In many parts of the country, water is contaminated by sewage and industrial waste, exposing those who drink it to disease.

The sad state of India's water supply is just one sign of what could become a global disaster. From the slums of Mexico to the overburdened farms of China, human populations are outstripping the limited stock of fresh water. Mankind is poisoning and exhausting the precious fluid that sustains all life.

In the Soviet Union, the mismanagement of land around the Aral Sea has cut it off from its sources of water, causing the volume of the once giant lake to shrink by two-thirds in 30 years. Now storms of salt and pesticides swirl up from the receding shoreline, contaminating the land and afflicting millions of Uzbeks with gastritis, typhoid and throat cancer. In Beijing, one-third of the city's wells have gone dry, and the water table drops by as much as 2 meters (2.2 yards) a year. In the Western U.S., four years of drought have left municipalities and agricultural interests tussling over diminishing water stocks. Says Ivan Restrepo, head of the Center for Ecodevelopment in Mexico, where as many as 30 million people do not have safe drinking water: "We've been enduring a crisis for several years now, but it is in this decade that it will explode."

) Camouflaged by its very familiarity, the water problem has crept up on a world distracted by fears of global warming and other emergent environmental threats. Yet water could be the first resource that puts a limit on human population and economic growth. Shortfalls of water will mean shortfalls of food, since up to three-quarters of the fresh water that humanity uses goes for agriculture. Moreover, contaminated drinking water in heavily populated areas endangers the health of hundreds of millions of people. According to the United Nations, 40,000 children die every day, many of them the victims of the water crisis.

At the moment, countries are poised to go to war over oil, but in the near future, water could be the catalyst for armed conflict. Israel and Jordan, Egypt and Ethiopia, and India and Bangladesh are but a few of the neighboring nations at odds over rivers and lakes. Warns Arnon Sofer, professor of geography at Israel's Haifa University: "Wars over water might erupt in the Middle East in the '90s when states try to control each other's supplies."

Whatever the human consequences of the crisis, it has an even greater effect on many other living things. Fish, birds and countless creatures are crowded out, marooned or poisoned as industry, agriculture and municipalities reroute rivers, dry up wetlands, dump waste and otherwise disrupt the normal functioning of delicate ecosystems. The world is learning that there are limits to mankind's ability to move water from one place to another without seriously upsetting the balance of nature.

The idea of a global shortage seems incredible when 70% of the earth's surface is covered by H2O. But 98% of that water is salty, making it unusable for drinking or agriculture. Desalinization is technically feasible, but it is far too expensive to use anywhere except in an ultra-rich, sparsely populated country like Saudi Arabia. Other options, like towing icebergs from the poles, are also beyond the means of poor nations.

The scarcity of fresh water for agriculture makes famines more likely every year. The world consumes more food than it produces, and yet there are few places to turn for additional cropland. Only by drawing on international stockpiles of grain have poorer countries averted widespread starvation. But those supplies are being depleted. From 1987 to 1989, the world's stock of grain fell from a 101-day surplus to a 54-day one. A drought in the U.S. breadbasket could rapidly lead to a global food calamity.

Even if rainfall stays at normal levels, current world food production will be difficult to maintain, much less increase. The food supply has kept pace with population growth only because the amount of land under irrigation has doubled in the past three decades. Now, however, agriculture is losing millions of hectares of this land to the effects of improper watering.

Without adequate drainage, continuous irrigation gradually destroys a piece of land -- and any streams or rivers near it -- through a process called salinization. As the heat of the sun evaporates irrigation water, salts are left behind. The water also flushes additional salts out of soils with high concentrations of minerals, leaving them to dry on the surface into a cakelike residue or to dissolve in groundwater and poison plant roots.

History shows that such environmental destruction can have far-reaching consequences. The salinization of irrigated land led to the fall of Mesopotamia and Babylon, and perhaps even the Mayan civilization of Central America. Similar pressures are at work today. Sandra Postel of Worldwatch Institute estimates that 60 million hectares (nearly 150 million acres) of irrigated land worldwide have been damaged by salt buildup.

Human activities have also disrupted the delicate natural systems that maintain water supplies. To obtain wood and clear land for homes and farms, mankind is chopping down forests at an unprecedented rate. But vegetation traps water, reducing runoff and replenishing groundwater supplies. Throughout the world, tree cutting has led to floods, mud slides and soil erosion during rainy seasons and acute water shortages during dry periods.

Deforestation can set in motion forces that reduce the amount of rainfall in a given area. In a rain forest, for example, as much as half the moisture settles on trees and quickly evaporates into the sky, only to precipitate again in a continuous cycle. Thus when trees are cut down, rainfall may diminish.

Even in dryer regions sparse shrubs can help maintain rainfall. Some scientists argue that once ground cover is stripped, the land hardens and evaporates less moisture into the air. At the same time, the naked soil reflects more sunlight, triggering atmospheric processes that reduce rainfall by drawing dryer air into the area.

The result is desertification, a gradual conversion of marginal land into wasteland. This process is often driven by population pressures, which force people to work lands unsuitable for agriculture. In sub-Saharan Africa, for instance, settlers move into an area when it is wet and green, and then stay and remove the ground cover when the inevitable drought returns. Without a green barrier to stop them, sand dunes march inexorably forward.

While no place is safe from the effects of the water crisis, Egypt, in particular, faces hard times. The country's population of 55 million is growing by 1 million every nine months. Already the people must import 65% of their food, and the situation could grow far worse. The flow of the Nile, Egypt's only major water supply, will be reduced in coming years as upstream neighbors Ethiopia and Sudan divert more of the river's waters. Egypt's only practical course is to brake population growth and reduce the enormous amount of water wasted through inefficient irrigation techniques.

Competition for water is especially fierce between Israel and Jordan, which must share the Jordan River basin. Many towns in Jordan receive water only two times a week, and the country must double its supply within 20 years just to keep up with population growth. "We are cornered," admits Munther Haddadin, a Jordanian development official. With time running out, Jordan hopes to draw additional reserves from the Yarmuk river. Israel, however, will fight any plans for use of the river that do not give guarantees of access to the Yarmuk waters that the country currently uses.

In the grip of a three-year drought, Israel too is far from secure, despite its formidable conservation technologies. An expected 750,000 Soviet emigres will probably settle in the cities, where the use of pure water is the highest. At the same time, 750,000 Palestinians in the Gaza Strip face what Zemah Ishai, Israel's water commissioner, calls a "catastrophe" because of overpumping and contamination of groundwater.

A decade ago, a government study in China estimated that the nation's water resources might support only 700 million people. That was alarming, since the population had already reached 900 million. Unable to increase the supply, the Politburo took the simpler expedient of revising the study to conclude that there was enough water for 1.1 billion people. As the population continues to grow and now surpasses the 1.1 billion mark, China has gradually increased the numbers in the study.

Chinese leaders, aware of the true severity of the crisis, have at last begun to focus the nation's scientific talent on the water issue. The country has been working to develop salt-tolerant and drought-resistant crops, and it has begun to have some success in reclaiming salt-damaged land.

In the West the most troubled dry spot is Mexico, where a government report asserts that "water will be a limiting factor for the country's future development." The demands of Mexico City's 20 million people are causing the level of their main aquifer to drop as much as 3.4 meters (11 ft.) annually. Water subsidies encourage the wealthy and middle classes to waste municipal supplies, while the poor are forced to buy from piperos, entrepreneurs who fix prices according to demand. Belatedly, the government has begun to establish a more sensible system of tariffs as well as promote water-saving devices like low-flush toilets.

Despite the global breadth of the water crisis, the situation is not completely hopeless. In industrial nations the revitalized environmental movement has spawned a fresh offensive against pollution. Jan Dogterom, who runs a consulting firm in the Netherlands, represents a new breed of detective hired by governments to track down the culprits who contaminate waterways. Faced with the knowledge that toxins can be traced back to their source, many companies comply readily in cleanup efforts. Says Dogterom: "It is my honest- to-God conviction that the West European rivers will be clean in 50 years, and the East European rivers will soon follow."

The water-supply picture may not be entirely bleak. Mohamed El-Ashry of the World Resources Institute estimates that around the world 65% to 70% of the water people use is lost to evaporation, leaks and other inefficiencies. The U.S. has a slightly better 50% efficiency, and El-Ashry believes it is economically feasible to reduce losses to 15%.

Government officials and businesses are looking for ways to reuse waste water. With the aid of advanced technology, even highly contaminated water can be made drinkable again. Alcoa has just begun to market a new claylike material called Sorbplus that helps clean water by adsorbing toxic materials.

Most tantalizing of all is the possibility that there are great, undiscovered reservoirs throughout the globe. Speaking in Cairo last June at a water summit organized by the Washington-based Global Strategy Council, Farouk El-Baz of Boston University raised hopes among African nations when he announced that an analysis of remote sensing data has revealed unsuspected supplies of underground water in the dryest part of the Egyptian Sahara. El- Baz believes there may be twice as much water stored underground worldwide as previously assumed.

New supplies could take some pressure off rivers and lakes and would be a temporary godsend to millions of people. But if societies returned to business as usual, this bounty would only postpone the day of reckoning for humans and all other species. Humanity has long deluded itself into thinking that water shortages merely reflect temporary problems of distribution. Both industrial and developing nations are finally realizing that the world's fresh water is a finite and vulnerable resource, an irreplaceable commodity that must be respected and preserved.

CHART: NOT AVAILABLE

CREDIT: TIME Chart by Joe Lertola

CAPTION: UNEQUAL ACCESS

With reporting by Andrea Dabrowski/Mexico City, Anita Pratap/New Delhi and Amany Radwan/Amman