This article is from World Watch regarding China's Water Shortage.
An unexpectedly abrupt
decline in the supply of water for China's
farmers poses a rising threat to world food security. China depends on
irrigated land to produce 70 percent of the grain for its huge
population of 1.2 billion people, but it is drawing more and more of
that water to supply the needs of its fast-growing cities and
industries. As rivers run dry and aquifers are depleted, the emerging
water shortages could sharply raise the country's demand for grain
imports, pushing the world's total import needs beyond exportable
Any major threat to China's food self-sufficiency, if not addressed
strong new measures, would likely push up world grain prices, creating
social and political instabilities in Third World cities-as previous
WORLD WATCH articles have pointed out (see commentary). New information
on the deteriorating water situation has confirmed the imminence of this
possibility. The challenge now facing the Chinese government is how to
meet the soaring water needs of its swelling urban and industrial
sectors without undermining both its own agriculture and the world's
The decline in China's capacity to irrigate its crops-signs
include the drying-up of rivers and wells all over the northern region
of the country-is coming at a time when depleted world grain stocks are
near an all-time low. With its booming economy and huge trade surpluses,
China can survive its water shortages by simply importing more of its
food, because it can afford to pay more for grain. But low-income
countries with growing grain deficits may not be able to pay these
higher prices. For the 1.3 billion of the world's people who live on $1
a day or less, higher grain prices could quickly become life
threatening. The problem is now so clearly linked to global security
that the U.S. National Intelligence Council (NIC) the umbrella over all
U.S. intelligence agencies, has begun to monitor the situation with the
kind of attention it once focused on Soviet military maneuvers.
This deepening concern led the NIC to sponsor a major interdisciplinary
assessment of China's food prospect. Headed by Michael McElroy, chairman
of Harvard University's Department of Earth and Planetary Sciences, the
study used information from intelligence satellites to refine cropland
area estimates, and commissioned computer modeling by the Sandia
National Laboratory to assess the extent of future water shortages in
each of China's river basins. The recently released study concluded that
China will need massive grain imports in the decades ahead-a conclusion
that meshes with earlier projections published by WORLD WATCH.
Signs of Stress
SINCE MID-CENTURY, the population of China has grown by nearly
million-an increase almost equivalent to adding the whole population of
the world at the beginning of the Industrial Revolution. Most of that
population has concentrated in the region through which several great
rivers, including the Yellow and the Yangtze, flow. Those rivers provide
the irrigation water needed to grow much of the food for China, as well
as the water for its burgeoning cities and industries.
This dependence has placed a growing burden on the region's
water resources, because the Chinese population has not been able to
expand into new land the way the Americans once did with their westward
expansion into the Great Plains and California. In China, the western
half of the country is mostly desert or mountains. The resulting
concentration of Chinese population, industry, and agriculture has been
roughly equivalent to squeezing the entire U.S. population into the
region east of the Mississippi, then multiplying it by five.
A quarter-century ago, with more and more of its water being
for the country's multiplying needs, the Yellow River began to falter.
In 1972, the water level fell so low that for the first time in China's
long history it dried up before reaching the sea. It failed on 15 days
that year, and intermittently over the next decade or so. Since 1985, it
has run dry each year, with the dry period becoming progressively
longer. In 1996, it was dry for 133 days. In 1997, a year exacerbated by
drought, it failed to reach the sea for 226 days. For long stretches, it
did not even reach Shandong Province, the last province it flows through
en route to the sea. Shandong, the source of one-fifth of China's corn
and one-seventh of its wheat, depends on the Yellow River for half of
its irrigation water.
Although it is perhaps the most visible manifestation of water
in China, the drying-up of the Yellow River is only one of many such
signs. The Huai, a smaller river situated between the Yellow and
Yangtze, was also drained dry in 1997, and failed to reach the sea for
90 days. Satellite photographs show hundreds of lakes disappearing and
local streams going dry in recent years, as water tables fall and
springs cease to flow. As water tables have fallen, millions of Chinese
farmers are finding their wells pumped dry.
In the geography of water, there are two Chinas. The humid
includes the vast Yangtze River and a population of 700 million. The
arid north includes the Yellow, Liao, Hai, and Huai Rivers, and has 550
million. While four-fifths of the water is in the south, two-thirds of
the cropland is in the north. As a result, the water per hectare of
cropland in the north is only one-eighth that in the south.
Although comprehensive hydrological data are not always available,
pieces of the water puzzle are beginning to emerge from various sources.
A recent Chinese survey reported by Professor Liu Yonggong of China
Agricultural University in Beijing indicated that the water table
beneath much of the North China Plain, a region that produces some 40
percent of China's grain, has fallen an average of 1.5 meters (roughly 5
feet) per year over the last five years. A joint Sino-Japanese analysis
of China's agricultural prospect reports that water tables are falling
almost everywhere in China that the land is flat.
In the late summer of 1997, many of the irrigation wells in
Province, which was experiencing its worst drought in 25 years, were not
pumping. Chinese water analysts report frenzied well-drilling in some
provinces as farmers chased the falling water table downward.
Of course, those farmers' ability to provide food enough for
nation is constrained by a range of factors in addition to water-by the
construction of roads over once-productive farmland, by erosion of soil,
by the diminishing benefits of fertilizer, and by a shrinking backlog of
the technology used to raise land productivity. But it is the swelling
diversion of irrigation water, combined with heavy losses to aquifer
depletion, that has emerged as the most imminent threat to China's food
Projected Demand for Water
EVEN AS THE YELLOW RIVER, aquifers, and wells get drier, the
water needed continues to swell. Between now and 2030, UN demographers
project that China's population will increase from 1.2 billion to 1.5
billion, an increase that exceeds the entire population of the United
States. Even if there were no changes in water consumption per person,
this would boost the demand for water by one fourth above current
levels-but per-person consumption, too, is growing. It is expected to
grow in all three of the end use sectors-agricultural, residential, and
In the agricultural sector, demand for irrigation water, now
billion cubic meters or tons per year, is expected to reach 665 billion
tons in 2030. As incomes rise, people are consuming more pork, poultry,
beef, and eggs, and feedgrain use is growing. For example, to produce
one kilogram of pork it takes four kilograms of grain, and one kilogram
of chicken takes two kilograms of grain. More grain means more water
(see Figure 1). Between 1990 and 1997, consumption of pork climbed by a
phenomenal 9 percent per year. Consumption of both beef and poultry,
starting from a much smaller base, has climbed at over 20 percent per
year. The brewing of beer, which is also made from grain, is growing at
7 percent annually.
In the residential sector, a similar compounding is occurring.
present, some 85 percent of all water withdrawals are for irrigation,
but the residential share is increasing as China's population urbanizes
and hundreds of millions turn from the village well to indoor plumbing
with showers and flush toilets. Combined with projected increases in
population, rising individual water use will boost residential water use
from 31 billion tons in 1995 to 134 billion tons in 2030, a gain of more
The demand for water by industry is growing even faster. Assuming
economic growth of 5 percent a year from 1995 until 2030 (actual growth
in the past decade has been more than twice that rate), industrial water
use would increase from 52 billion tons to 269 billion tons (see table).
The increase in residential and industrial water use together would
total 320 billion tons of water during this 25-year span. If this water
were used for irrigation, at 1,000 tons of water required per ton of
grain produced, it would yield 320 million tons of grain, an amount
approaching China's 1997 grain harvest of 380 million tons.
In other words, non-agricultural uses that are now straining
by drawing only 15-percent of the supply would multiply nearly five
times, while the agricultural needs now taking 85 percent would have
increased as well. Obviously, that can't happen. Because consumption
can't exceed the sustainable supply for long, China is facing
fundamental changes in the way it distributes and uses its water.
Diversion, Depletion, and Pollution
THOUGH 70-PERCENT OF THE GRAIN produced in China comes from
land, the country is seeing its irrigation supply depleted on three
fronts: the diversion of water from rivers and reservoirs to cities; the
depletion of underground supplies in aquifers; and the increasing
pollution caused by rapid industrialization. Politically, it is
difficult for any government to deny people water for their showers and
toilets, if they can afford to buy it-and China's urbanizing population
increasingly can. And economically, farms can't compete with factories
for water. As competition among farms, homes, and industries
intensifies, farms inevitably lose out.
Of China's 617 cities, 300 are already facing water shortages.
areas of north China where all available water is being used, these
shortfalls can be filled only by diverting water from agriculture. In
the spring of 1994, farmers in the region surrounding Beijing were
denied access to reservoirs, their traditional source of irrigation
water, because all the water was needed to satisfy the city's burgeoning
demand. That established a pattern for water-stressed cities all over
the north North China Plain
As for the demand from industry, agriculture simply cannot
China or anywhere else. A thousand tons of water produces one ton of
wheat, which has a market value of $200, whereas the same amount of
water used in industry yields an estimated $14,000 of output-70 times as
much. Moreover, that economic advantage is reinforced by a political
one: the need to provide jobs for some 14 million new entrants into the
labor force each year. And, as China's old state-run corporations are
cut back, massive layoffs are leaving millions of people unemployed. As
it happens, water used in industry can also create a disproportionately
large number of jobs. Since incomes are much higher in industry than in
agriculture, the number of jobs a given amount of water can bring to
industry versus agriculture is somewhat less than the 70 to 1 just
mentioned, but the bottom line still is that shifting irrigation water
to industry creates many more jobs.
While farmers are losing out to cities and industries politically,
are also losing ground hydrologically. As the demand for underground
water increases over time, the pumping eventually surpasses the natural
recharge of the aquifer, which comes from precipitation in the upstream
portion of the watershed. After this "sustainable yield threshold" is
passed, the water table starts to fall. If demand continues to climb,
the excess of pumping over the sustainable yield of the aquifer widens
each year. As a result, the distance the water table falls increases
Once the aquifer is depleted, the amount of water pumped is
the rate of recharge. It cannot be otherwise. If the pumping has been
taking place at double the recharge when depletion occurs, then the
pumping will be cut by half. If pumping has been five times the
recharge, it will be cut by four fifths. Under the North China Plain, if
the water table is falling 1.5 meters per year, then the pumping could
easily be occurring at double the recharge rate. And if it is, the time
will come when the amount of water pumped in this wheat and corn belt
will be necessarily cut by half.
When farmers lose irrigation water, they either revert to rainfed
farming if rainfall is sufficient or they abandon the land if it is not.
For China, most of the land will simply revert to rainfed agriculture.
The yield will then decline by about one-half to two-thirds.
Unfortunately, even this stark arithmetic fails to fully convey
extent to which China's grainland irrigation water is being lost,
because it doesn't account for losses to pollution. There are 50,000
kilometers of major rivers in China, and, according to the UN Food and
Agriculture Organization, 80 percent of them are so degraded they no
longer support fish. As a result of toxic discharge from cities and
upstream enterprises, which include such highly polluting industries as
paper mills, tanneries, oil-refineries and chemical plants, the Yellow
River water is now loaded with heavy metals and other toxins that make
it unfit even for irrigation, much less for human consumption, along
much of its route.
Water pollution horror stories abound throughout China as farmers-for
want of a cleaner source-irrigate with heavily polluted water. In Shanxi
province, in the Yellow River watershed, rice has been found to contain
excessive levels of chromium and lead, and the cabbage is laced with
cadmium. Along the length of the Yellow River, abnormally high rates of
mental retardation, stunting and developmental diseases are linked to
elevated concentrations of arsenic and lead in the water and food.
As industrialization outpaces pollution control, more and more
water is rendered unsuitable for irrigation. In the heavily
industrialized, heavily populated Yangtze valley, it may not be the
diversion of water to industry that most threatens agriculture, but the
pollution of water by industry, which renders it unsuitable for
irrigation to begin with.
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