Water shortages threaten China's harvest

Posted: 15 October 2001

Author: Lester R. Brown

Author Info: Institute based in Washington DC.

A little-noticed survey released in Beijing in mid-August (2001) reveals that China's water situation is far more serious than realized. The water table under the North China Plain, which produces over half of China's wheat and a third of its corn, is falling faster than thought.

Overpumping has largely depleted the shallow aquifer, reducing the amount of water that can be pumped from it to the amount of recharge from precipitation. This is forcing well drillers to go down to the region's deep aquifer, which, unfortunately, is not replenishable.

The study, conducted by the Geological Environmental Monitoring Institute (GEMI) in Beijing, reported that under Heibei Province in the heart of the North China Plain, the average level of the deep aquifer dropped 2.9 metres (nearly 10 feet) in 2000. Around some cities in the province, it fell by 6 metres.

He Qingcheng, head of the GEMI groundwater monitoring team, believes the fast-deteriorating water situation should be getting far more official attention. He notes that with depletion of the deep aquifer under the North China Plain, the region is losing its last water reserve-its only safety cushion.

Frenzy of drilling

His concerns are mirrored in a new World Bank report that says, "Anecdotal evidence suggests that deep wells [drilled] around Beijing now have to reach 1,000 metres (more than half a mile) to tap fresh water, adding dramatically to the cost of supply." In unusually strong language for a Bank report, it forecasts "catastrophic consequences for future generations" unless water use and supply can quickly be brought back into balance.

Further evidence of the gravity of the water situation in the North China Plain can be seen in the frenzy of well drilling in recent years. At the end of 1996, the five provinces of the North China Plain-Heibei, Henan, Shandong, and the city provinces of Beijing and Tianjin-had 3.6 million wells, the bulk of them for irrigation. During 1997, 99,900 wells were abandoned as they ran dry. Some 221,900 new wells were drilled. The desperate quest for water in China is evident as well drillers chase the water table downward.

The northern half of China is drying out. Demands on the three rivers that flow eastward into the North China Plain-the Hai, the Yellow, and the Huai-are excessive, leading them to run dry during the dry season, sometimes for extended periods of time. The flow of the Yellow River into Shandong Province-the last of the eight provinces it flows through en route to the sea, and China's leading grain-producing province-has been reduced from 40 billion cubic metres (1 cu. metre = 1 ton) a year in the early 1980s to 25 billon cubic metres during the 1990s.

As water tables fall, springs dry up, streams cease to flow, rivers run dry, and lakes disappear. Hebei Province once had 1,052 lakes. Only 83 remain.

The water deficit in the North China Plain, the excess of use over the sustainable supply, may now exceed 40 billion tons per year. At present that deficit is being filled by groundwater mining, but when aquifers are depleted and there is nothing more to mine, the basin's water supply will be cut by nearly 40 per cent. In the Hai River basin-where industry and cities, including Beijing and Tianjin, now get priority-irrigated agriculture could largely disappear by 2010, forcing a shift back to less productive rain-fed agriculture.

Growing population

Between now and 2010, when China's population is projected to grow by 126 million, the World Bank projects that the country's urban water demand will increase from 50 billion cubic metres to 80 billion, a growth of 60 per cent. Industrial water demand, meanwhile, will increase from 127 billion to 206 billion cubic metres, an expansion of 62 per cent.

With water worth easily 70 times as much in industry as in agriculture, farmers almost always lose in the competition with cities. As water tables continue to fall, rising pumping costs will make underground water too costly for many farmers to use for irrigation.

In addition to spreading water scarcity, numerous environmental and economic forces are reducing China's grain production. As farmers attempt to maximize their income from small plots, for example, they are shifting from grain to high-value fruit and vegetable crops.

China has been striving valiantly to remain self-sufficient in grain since 1994. It did so by raising support prices of grain well above the world market level, by overploughing land on a scale that helped create the world's largest dust bowl, and by overpumping the aquifers under the North China Plain.

The combination of weak prices, falling water tables, and severe drought reduced the grain harvest in 2001 to 335 million tons, down from the all-time high of 392 million tons in 1998. This will fall short of projected consumption by 46 million tons. The emergence of this deficit-easily the largest in China's history-on the heels of last year's deficit of 34 million tons raises questions about future food security.

If China has another sizable grain harvest shortfall in 2002, it will probably be forced to import grain far in excess of the 7 million tons of wheat and 5 million tons of corn that it must promise to import if it joins the World Trade Organization in late 2001, as expected.

With its aquifers being depleted, China is now reconsidering its options for reestablishing a balance between water use and supply. Three possible initiatives stand out: water conservation, diversion of water from the south to the north, and grain imports. A south/north diversion to transport water from the Yangtze River basin will cost tens of billions of dollars and displace hundreds of thousands of people.

A comparable investment in more water-efficient industrial practices, more water-efficient household appliances, and, above all, the use of more-efficient irrigation practices would likely yield more water. Since it takes 1,000 tons of water to produce 1 ton of grain, importing grain is the most efficient way to import water.

Regardless of whether it concentrates solely on conservation or also does a south/north diversion, China will almost certainly have to turn to the world market for grain imports. If it imports even 10 per cent of its grain supply - 40 million tons - it will become overnight the largest grain importer, putting intense pressure on exportable grain supplies and driving up world prices. If this happens, we probably won't need to read about it in the newspapers. It will be evident at the supermarket checkout counter.

Lester Brown is President of the Earth Policy