August 6, 2002-11
Copyright © 2002 Earth Policy Institute
WATER DEFICITS GROWING IN MANY COUNTRIES
Water Shortages May Cause Food Shortages
Lester R. Brown
The world is incurring a vast water
deficit. It is largely invisible, historically recent, and growing
fast. Because this impending crisis typically takes the form of
aquifer overpumping and falling water tables, it is not visible.
Unlike burning forests or invading sand dunes, falling water tables
cannot be readily photographed. They are often discovered only when
wells go dry.
The world water deficit is recent--a product of the tripling of
water demand over the last half-century and the rapid worldwide
spread of powerful diesel and electrically driven pumps. The drilling
of millions of wells has pushed water withdrawals beyond the recharge
of many aquifers. The failure of governments to limit pumping to
the sustainable yield of aquifers means that water tables are now
falling in scores of countries.
We are consuming water that belongs to future generations. In some
countries, the fall of water tables is dramatic. In Yemen, a country
of 19 million, the water table under most of the country is falling
by roughly 2 meters a year as water use far exceeds the sustainable
yield of aquifers. World Bank official Christopher Ward observes
that "groundwater is being mined at such a rate that parts of the
rural economy could disappear within a generation."
In the basin where the capital, Sana'a, is located and where the
water table is falling 6 meters (nearly 20 feet) per year, the aquifer
will be depleted by the end of this decade. In the search for water,
the Yemeni government has drilled test wells in the basin that are
2 kilometers (1.2 miles) deep, depths normally associated with the
oil industry, but they have failed to find water. Yemen must soon
decide whether to bring water to Sana'a, possibly from coastal desalting
plants, or to relocate the capital.
Iran, a country of 70 million people, is facing an acute shortage
of water. Under the agriculturally rich Chenaran Plain in northeastern
Iran, the water table was falling by 2.8 meters a year in the late
1990s. But in 2001 the cumulative effect of a three-year drought
and the new wells being drilled both for irrigation and to supply
the nearby city of Mashad dropped the aquifer by an extraordinary
8 meters. Villages in eastern Iran are being abandoned as wells
go dry, generating a swelling flow of water refugees.
Shortages of water in Egypt, which is entirely
dependent on the Nile River, are well known. With the Nile now reduced
to a trickle as it enters the Mediterranean, the three principal
countries of the Nile River Basin--Egypt, Ethiopia, and Sudan--can
each increase its take from the river only at the expense of the
other two. With the combined population of these countries projected
to climb from 167 million today to 264 million in 2025, all three
are facing growing grain deficits as a result of water shortages.
In Mexico--home to 104 million people and growing by 2 million per
year--the demand for water has outstripped supply in many states.
In the agricultural state of Guanajuato, for example, the water
table is falling by 1.8-3.3 meters a year. Mexico City's water problems
are legendary. How the United States and Mexico share the water
of the Rio Grande has become a thorny issue in U.S.-Mexican relations.
A World Bank study of the water balance in the North China Plain
calculated an annual deficit of 37 billion tons of water. Using
the rule of thumb of 1,000 tons of water to produce 1 ton of grain,
this is equal to 37 million tons of grain--enough to feed 111 million
Chinese at their current level of consumption. In effect, 111 million
Chinese are being fed with grain produced with water that belongs
to their children. Scores of other countries are running up regional
water deficits, including nearly all of those in Central Asia, the
Middle East, and North Africa, plus India, Pakistan, and the United
States.
Historically, water shortages were local, but in an increasingly
integrated world economy, the shortfalls can cross national boundaries
via the international grain trade. Water-scarce countries often
satisfy the growing needs of cities and industry by diverting water
from irrigation and importing grain to offset the resulting loss
of production. Since a ton of grain equals 1,000 tons of water,
importing grain is the most efficient way to import water. World
grain futures will soon in effect become world water futures.
Although military conflicts over water are always a possibility,
future competition for water seems more likely to take place in
world grain markets. This can be seen with Iran and Egypt, both
of which now import more wheat than Japan, traditionally the world's
leading importer. Imports supply 40 percent or more of the total
consumption of grain--wheat, rice, and feedgrains--in both countries.
Numerous other water-short countries also import much of their grain.
Morocco brings in half of its grain. For Algeria and Saudi Arabia,
the figure is over 70 percent. Yemen imports nearly 80 percent of
its grain, and Israel, more than 90 percent.
Seventy percent of world water use, including all the water diverted
from rivers and pumped from underground, is used for irrigation,
20 percent is used by industry, and 10 percent goes to residences.
Thus if the world is facing a water shortage, it is also facing
a food shortage. Water deficits, which are already spurring heavy
grain imports in numerous smaller countries, may soon do the same
in larger countries, such as China or India.
Even with the overpumping of its aquifers, China is developing a
grain deficit. After rising to an historical peak of 392 million
tons in 1998, grain production in the world's largest nation fell
below 350 million tons in 2000, 2001, and 2002. The resulting annual
deficits of 40 million tons or so have been filled by drawing down
the country's extensive grain reserves. But if this situation continues,
China soon will be forced to turn to the world grain market.
When this happens, it will almost certainly drive grain prices upward.
Remember that when the Soviets decided after a poor harvest in 1972
to import grain rather than tighten their belts, the world wheat
price climbed from $1.90 per bushel in 1972 to $4.89 in 1974.
The two keys to stabilizing aquifers are raising water prices and
stabilizing population. The first step is to eliminate the pervasive
subsidies that create artificially low prices for water in so many
countries. The next is to raise water prices to the point where
they will reduce pumping to a sustainable level by raising water
productivity and reducing water use in all segments of society.
Low-income urban consumers can be protected with "lifeline rates"
that provide for basic needs at an affordable price. Prices of underground
water can be raised by installing meters on pumps and charging for
water as Mexico has done or by auctioning permits to operate wells.
Either way, water prices rise.
The second key is to quickly stabilize population in water-short
countries. Most of the 3 billion people projected to be added worldwide
by mid-century will be born in countries already experiencing water
shortages. Unless population growth can be slowed quickly by investing
heavily in female literacy and family planning services, there may
not be a humane solution to the emerging world water shortage.
See
Additional Data and Graph
Copyright
© 2002 Earth Policy Institute
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FOR ADDITIONAL INFORMATION
From Earth Policy Institute
Lester R. Brown, Eco-Economy:
Building an Economy for the Earth (New York: W.W. Norton
& Company, 2001).
Lester R. Brown, "World Grain Harvest Falling Short
by 54 Million Tons: Water Shortages Contributing to Shortfall,"
Eco-Economy
Update, 21 November 2001.
Lester R. Brown, "Worsening Water Shortages Threaten
China's Food Security," Eco-Economy
Update, 4 October 2001.
From Other Sources
Peter Gleick, The World's Water (Washington,
DC: Island Press, various years).
Sandra Postel, Pillar of Sand (New York:
W.W. Norton & Company and Worldwatch Institute, 1999).
Sandra Postel, Last Oasis: Facing Water Scarcity
(New York: W.W. Norton & Company and Worldwatch Institute, 1997).
LINKS
AQUASTAT, global information system of water and
agriculture from the Land and Water Development Division of the
U.N. Food and Agriculture Organization
http:/www.fao.org/ag/agl/aglw
/aquastat/main/index.stm
International Water Management Institute
http:/www.iwmi.cgiar.org/
The World's Water
http:/www.worldwater.org
United Nations Environment Programme, UNEP Freshwater
Site
http:/freshwater.unep.net
Worldwatch Institute, Water Mini Site
http:/www.worldwatch.org/
taxonomy/term/102
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