China's Three Gorges Dam: An Environmental Catastrophe?

For over three decades, the Chinese government has dismissed warnings from scientists and environmentalists that its Three Gorges Dam—the world's largest—had the potential of becoming one of China's biggest environmental nightmares. But last fall, denial suddenly gave way to reluctant acceptance that the naysayers were right. Chinese officials staged a sudden about-face, acknowledging for the first time that the massive hydroelectric dam, sandwiched between breathtaking cliffs on the Yangtze River in central China, may be triggering landslides, altering entire ecosystems and causing other serious environmental problems—and, by extension, endangering the millions who live in its shadow.

Government officials have long defended the $24-billion project as a major source of renewable power for an energy-hungry nation and as a way to prevent floods downstream. When complete, the dam will generate 18,000 megawatts of power—eight times that of the U.S.'s Hoover Dam on the Colorado River. But in September, the government official in charge of the project admitted that Three Gorges held "hidden dangers" that could breed disaster. "We can't lower our guard," Wang Xiaofeng, who oversees the project for China's State Council, said during a meeting of Chinese scientists and government reps in Chongqing, an independent municipality of around 31 million abutting the dam. "We simply cannot sacrifice the environment in exchange for temporary economic gain."

The comments appeared to confirm what geologists, biologists and environmentalists had been warning about for years: building a massive hydropower dam in an area that is heavily populated, home to threatened animal and plant species, and crossed by geologic fault lines is a recipe for disaster.

Among the damage wrought: "There's been a lot less rain, a lot more drought, and the potential for increased disease," says George Davis, a tropical medicine specialist at The George Washington University (G.W.) Medical Center in Washington, D.C., who has worked in the Yangtze River Basin and neighboring provinces for 24 years. "When it comes to environmental change, the implementation of the Three Gorges dam and reservoir is the great granddaddy of all changes."

Dam Quake
When plans for the dam were first approved in 1992, human rights activists voiced concern about the people who would be forced to relocate to make room for it. Inhabited for several millennia, the Three Gorges region is now a major part of western China's development boom. To date, the government has ordered some 1.2 million people in two cities and 116 towns clustered on the banks of the Yangtze to be evacuated to other areas before construction, promising them plots of land and small stipends—in some cases as little as 50 yuan, or $7 a month—as compensation.

Chinese and foreign scientists, meanwhile, warned that the dam could endanger the area's remaining residents. Among their concerns: landslides caused by increased pressure on the surrounding land, a rise in waterborne disease, and a decline in biodiversity. But their words fell on deaf ears. Harnessing the power of the Yangtze has been a goal since Nationalist leader Sun Yat-sen first proposed the idea in 1919. Mao Zedong, the father of China's communist revolution, rhapsodized the dam in a poem. The mega- project could not be realized in his lifetime, however, because the country's resources were exhausted by the economic failures of the Great Leap Forward in the late 1950s and then the social upheaval of the Cultural Revolution from the mid-1960s a to the early 1970s. Four decades later, the government resuscitated Mao's plans. The first of the Yangtze's famed gorges—a collection of steep bluffs at a bend in the river—was determined to be the perfect site.

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