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WORLD CREATING FOOD BUBBLE ECONOMY
BASED ON UNSUSTAINABLE USE OF WATER
Lester R. Brown
On March 16, 2003, some 10,000 participants will
meet in Japan for the third World Water Forum to discuss the world
water prospect. Although they will be officially focusing on water
scarcity, they will indirectly be focusing on food scarcity because
70 percent of the water we divert from rivers or pump from underground
is used for irrigation.
As world water demand has tripled over the last
half-century, it has exceeded the sustainable yield of aquifers
in scores of countries, leading to falling water tables. In effect,
governments are satisfying the growing demand for food by overpumping
groundwater, a measure that virtually assures a drop in food production
when the aquifer is depleted. Knowingly or not, governments are
creating a "food bubble" economy.
As water use climbs, the world is incurring a
vast water deficit, one that is largely invisible, historically
recent, and growing fast. Because the impending water crunch typically
takes the form of falling water tables, it is not visible. Falling
water tables are often discovered only when wells go dry.
Once the growing demand for water rises above
the sustainable yield of an aquifer, the gap between the two widens
each year. The first year after the line is crossed, the water table
falls very little, with the drop often being scarcely perceptible.
Each year thereafter, however, the annual drop is larger than the
year before.
The diesel-driven or electrically powered pumps
that make overpumping possible have become available throughout
the entire world at essentially the same time. The near-simultaneous
depletion of aquifers means that cutbacks in grain harvests will
be occurring in many countries at more or less the same time. And
they will be occurring at a time when world population is growing
by more than 70 million a year.
Aquifers are being depleted in scores of countries,
including China, India, and the United States, which collectively
account for half of the world grain harvest. Under the North China
Plain, which produces more than half of China's wheat and a third
of its corn, the annual drop in the water table has increased from
an average of 1.5 meters a decade ago to up to 3 meters today. Overpumping
has largely depleted the shallow aquifer, so the amount of water
that can be pumped from it each year is restricted to the annual
recharge from precipitation. This is forcing well drillers to go
down to the region's deep aquifer, which, unfortunately, is not
replenishable.
He Quincheng, head of the Geological Environmental
Monitoring Institute in Beijing, notes that as the deep aquifer
under the North China Plain is depleted, the region is losing its
last water reserve--its only safety cushion. His concerns are mirrored
in a World Bank report: "Anecdotal evidence suggest that deep
wells [drilled] around Beijing now have to reach 1,000 meters [more
than half a mile] to tap fresh water, adding dramatically to the
cost of supply." In unusually strong language for the Bank,
the report forecasts "catastrophic consequences for future
generations" unless water use and supply can quickly be brought
back into balance.
India, which now has a billion people, is overdrawing
aquifers in several states, including the Punjab (the country's
breadbasket), Haryana, Gujarat, Rajasthan, Andhra Pradesh, and Tamil
Nadu. The latest data indicate that under the Punjab and Haryana,
water tables are falling by up to 1 meter per year. David Seckler,
former head of the International Water Management Institute, estimates
that aquifer depletion could reduce India's grain harvest by one
fifth.
In the United States, the underground water table
has dropped by more than 30 meters (100 feet) in parts of Texas,
Oklahoma, and Kansas--three key grain-producing states. As a result,
wells have gone dry on thousands of farms in the southern Great
Plains.
Pakistan, a country with 140 million people and
still growing by 4 million per year, is also overpumping its aquifers.
In the Pakistani part of the fertile Punjab plain, the drop in the
water table appears to be similar to that in India. In the province
of Baluchistan, a more arid region, the water table around the provincial
capital of Quetta is falling by 3.5 meters per year. Richard Garstang,
a water expert with the World Wildlife Fund, says that "within
15 years Quetta will run out of water if the current consumption
rate continues."
In Yemen, the water table is falling by roughly
2 meters a year. In its search for relief, the Yemeni government
has drilled test wells in the Sana'a basin, where the capital is
located, that are 2 kilometers (1.2 miles) deep--depths normally
associated with the oil industry--yet it has failed to find water.
With a population of 19 million growing at 3.3 percent a year, one
of the highest rates in the world, and with water tables falling
everywhere, Yemen is fast becoming a hydrological basket case. 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 Mexico--home to a population of 104 million
that is projected to reach 150 million by 2050--the demand for water
is outstripping supply. In the agricultural state of Guanajuato,
for example, the water table is falling by 2 meters or more a year.
At the national level, 52 percent of all the water extracted from
underground is coming from aquifers that are being overpumped.
Water scarcity, once a local issue, is now crossing
international boundaries via the international grain trade. Because
it takes a thousand tons of water to produce a ton of grain, importing
grain is the most efficient way to import water. Countries that
are pressing against the limits of their water supply typically
satisfy the growing need of cities and industry by diverting irrigation
water from agriculture, and then they import grain to offset the
loss of productive capacity. As water shortages intensify, so too
will the competition for grain in world markets. In a sense, trading
in grain futures is the same as trading in water futures.
In China, a combination of aquifer depletion,
the diversion of irrigation water to cities, and lower grain support
prices are shrinking the grain harvest. After peaking at 392 million
tons in 1998, the harvest dropped to 346 million tons in 2002. China's
food bubble may be about to burst. It has covered its grain shortfall
for three years by drawing down its stocks, but it will soon have
to turn to the world market to fill this deficit. When it does,
it could destabilize world grain markets.
Although some countries have already made impressive
gains in raising irrigation efficiency and recycling urban wastewater,
the general response to water scarcity has been to build more dams
or drill more wells. But now expanding supply is becoming more difficult.
The only other option is to reduce demand by stabilizing population
and raising water productivity. With nearly all the 3 billion people
to be added by 2050 being born in developing countries where water
is already scarce, achieving an acceptable balance between water
and people may now depend more on stabilizing population than on
any other single action.
The second step in stabilizing the water situation
is to raise water productivity, not unlike the way we have raised
land productivity. After World War II, with population projected
to double by 2000 and with little new land to bring under the plow,
the world launched a major effort to raise cropland productivity.
As a result, land productivity nearly tripled between 1950 and 2000.
Now it is time to see what we can do with water.
http://www.earth-policy.org/Updates/Update22.htm
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Lester R. Brown is author of the forthcoming book,
"Plan B: Rescuing a Planet Under Stress and a Civilization
in Trouble" from which this Update has been adapted.
Additional data and information sources at
www.earth-policy.org or
contact jlarsen@earth-policy.org
For reprint permission
contact rjkauffman@earth-policy.org
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