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"'Man must conquer nature,' declared the Party, but the result was that a once-fertile plain was wrecked by droughts alternating with violent flash flooding. The most extended period of drought was as long as 247 days in 1999, forcing cities and towns to build more reservoirs or to rely on wells chasing shrinking underground aquifers deeper and deeper underground. Although such massive engineering achievements have been trumpeted as among the greatest symbols of communist state power, 3,000 of these (ed. Yellow River basin) dams collapsed, including many along the Huai River. In August 1975, the Shimantan and Banqiao dams gave way, killing 240,000 by some accounts.
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All but a handful of the 300 tributaries that feed into the Hai River are now dry, with dire consequences for a population of 120 million people in the Hai river basin. But agricultural runoff from chemical fertilizers, industrial effluent and urban waste have rendered the water in most of its reservoirs undrinkable. In desperation, Tianjin ordered hundreds of officials to patrol the river banks to prevent theft of the precious water. The city has shut down public baths, saunas and other entertainment centers and rationed water to just eight cubic meters a month per person.
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Water quality is also a big problem. Most of the 20 billion tonnes of urban sewage that China's expanding cities produce each year is dumped straight into rivers and lakes. China now holds the unenviable record of producing as much organic water pollution as the United States, Japan and India combined. Experts calculate that 700 million Chinese consume drinking water contaminated with levels of animal and human waste that do not meet minimum state drinking-water standards. No one is sure what this means. Any research into the subject has been discouraged by the government but China's high rates of hepatitis A, diarrhea, and liver, stomach and esophageal cancer may be linked to the pollution."
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Much more at:
http://www.atimes.com/atimes/China/EH26Ad01.html