Hydrological poverty

AT a time when drought in the United States, Ethiopia and Afghanistan is in the news, it is easy to forget that far more serious water shortages are emerging as the demand for water in many countries simply outruns the supply. Water tables are now falling in every continent.

We live in a water-challenged world, one that is becoming more so each year as 80 million additional people stake their claims to the earth's water resources. Unfortunately, nearly all the projected three billion people to be added over the next half century will be born in countries that are already experiencing water shortages. Even now many in these countries lack enough water to drink, to satisfy hygienic needs and to produce food.

By 2050, India is projected to add 519 million people and China 211 million. Pakistan is projected to add nearly 200 million, going from 151 million at present to 348 million. Egypt, Iran and Mexico are slated to increase their populations by more than half by 2050. In these and other water-short countries, population growth is sentencing millions of people to hydrological poverty, a local form of poverty that is difficult to escape.

Even with today's six billion people, the world has a huge water deficit. Using data on overpumping for China, India, Saudi Arabia, North Africa and the U.S., Sandra Postel, author of Pillar of Sand: Can the Irrigation Miracle Last? calculates the annual depletion of aquifers at 160 billion cubic metres or 160 billion tonnes. Using the rule of thumb, that it takes 1,000 tonnes of water to produce one tonne of grain, this 160-billion- tonne water deficit is equal to 160 million tonnes of grain or one half the U.S.'s grain harvest.

At an average world grain consumption of just over 300 kg or one- third of a tonne per person a year, this would feed 480 million people. Stated otherwise, 480 million of the world's six billion people are being fed with grain produced with the unsustainable use of water.

Overpumping is a new phenomenon, one largely confined to the last half century. Only since the development of powerful diesel and electrically driven pumps have we had the capacity to pull water out of aquifers faster than it is replaced by precipitation.

Some 70 per cent of the water consumed worldwide, including both that diverted from rivers and that pumped from underground, is used for irrigation, while some 20 per cent is used by industry, and 10 per cent for residential purposes. In the increasingly intense competition for water among sectors, agriculture almost always loses. The 1,000 tonnes of water used in India to produce one ton of wheat worth perhaps $200 (Rs. 10,000) can also be used to expand industrial output by $10,000 (Rs. 5,00,000), or 50 times as much. This ratio helps explain why, in the American West, the sale of irrigation water rights by farmers to cities is an almost daily occurrence.

In addition to population growth, urbanisation and industrialisation also expand the demand for water. As developing country villagers, traditionally reliant on the village well, move to urban high-rise apartment buildings with indoor plumbing, their residential water use can easily triple. Industrialisation takes even more water than urbanisation.

Rising affluence in itself generates additional demand for water. As people move up the food chain, consuming more meat and dairy products, they use more grain. A U.S. diet, rich in livestock products, requires 800 kg of grain per person a year, whereas diets in India, dominated by a starchy food staple such as rice, typically need only 200 kg. Using four times as much grain per person means using four times as much water.

Once a localised phenomenon, water scarcity is now crossing national borders via the international grain trade. The world's fastest growing grain import market is North Africa and the West Asia, an area that includes Morocco, Algeria, Tunisia, Libya, Egypt and West Asia through Iran. Virtually every country in this region is simultaneously experiencing water shortages and rapid population growth.

As the demand for water in the region's cities and industries increases, it is typically satisfied by diverting water from irrigation. The loss in food production capacity is then offset by importing grain from abroad. Since one tonne of grain represents 1,000 tonnes of water, this becomes the most efficient way to import water.

Last year, Iran imported seven million tonnes of wheat, eclipsing Japan to become the world's leading wheat importer. This year, Egypt is also projected to move ahead of Japan. Iran and Egypt have nearly 70 million people each. Both populations are increasing by more than a million a year and both are pressing against the limits of their water supplies.

The water required to produce the grain and other foodstuffs imported into North Africa and West Asia last year was roughly equal to the annual flow of the Nile. Stated otherwise, the fast- growing water deficit of this region is equal to another Nile flowing into the region in the form of imported grain.

It is now often said that future wars in the region will more likely be fought over water than oil. Perhaps, but given the difficulty in winning a water war, the competition for water seems more likely to take place in world grain markets. The countries that will "win" in this competition will be those that are financially strongest, not those that are militarily strongest.

The world water deficit grows larger with each year, making it potentially more difficult to manage. If we decided abruptly to stabilise water tables everywhere by simply pumping less water, the world grain harvest would fall by some 160 million tonnes, or eight per cent, and grain prices would go off the top of the chart. If the deficit continues to widen, the eventual adjustment will be even greater.

Unless governments in water-short countries act quickly to stabilise population and to raise water productivity, their water shortages may soon become food shortages. The risk is that the growing number of water-short countries, including population giants China and India, with rising grain import needs will overwhelm the exportable supply in food surplus countries, such as the U.S., Canada and Australia. This in turn could destabilise world grain markets.

Another risk of delay in dealing with the deficit is that some low-income, water-short countries will not be able to afford to import needed grain, trapping millions of their people in hydrological poverty, thirsty and hungry, unable to escape.

Although there are still some opportunities for developing new water resources, restoring the balance between water use and the sustainable supply will depend primarily on demand-side initiatives, such as stabilising population and raising water productivity.

Governments can no longer separate population policy from the supply of water. And just as the world turned to raising land productivity a half century ago when the frontiers of agricultural settlement disappeared, so it must now turn to raising water productivity. The first step toward this goal is to eliminate the water subsidies that foster inefficiency.

The second step is to raise the price of water to reflect its cost. Shifting to more water-efficient technologies, more water- efficient crops and more water-efficient forms of animal protein offer a huge potential for raising water productivity. These shifts will move faster if the price of water more closely reflects its value.

LESTER R. BROWN

(c) Worldwatch Institute, Washington DC

Send this article to Friends by E-Mail

Section  : Features
Previous : Who speaks for Mohamana?
Next     : What's in a name?