(June 11, 2008) While earthquake damage sustained by the country’s dams may pose serious threats, many are turning to the dams themselves for explanations. Probe International Fellow Dai Qing says: “We must look carefully at the questions: How do dams impact earthquakes? How do earthquakes impact dams?”

Emily Geminder                                                                                                               MediaGlobal.org                                                                                                                                    June 11, 2008

Still reeling from the May 12 earthquake, Sichuan Province in China now looks fearfully towards the dams at the region’s epicenter. On May 25, for the first time since the earthquake two weeks earlier, the Water Resources Ministry acknowledged that nearly 3,000 dams and reservoirs in China had been damaged, with 69 on the brink of collapse.

While the damage sustained to the dams may pose serious threats of its own, many are turning to the dams themselves for explanations of China’s devastating losses. According to earthquake scientist Jeff Freymueller, director of the NASA-funded project to advise Chinese scientists on the Three Gorges Dam, cases of seismic activity and resulting damage have long been attributed to large-scale dams in what experts call “Reservoir-Induced Seismicity” (RIS).

“The impoundment of large reservoirs has been clearly shown 
to trigger earthquakes nearby,” Freymueller told MediaGlobal. “This is due to a combination of factors, including the direct weight of the water and the forcing of more groundwater into the ground.”

Dai Qing, an environmental activist who has led campaigns against building several Chinese dams, echoes these concerns: “We must look carefully at the questions: How do dams impact earthquakes? How do earthquakes impact dams?”

Amidst growing disquiet concerning the relationship between dams and earthquakes, many are voicing broader questions about the environmental sustainability and social impact of large-scale dams. Hydropower dams, which produce minimal carbon emissions, have been touted as cheap, “green” sources of electricity. Yet critics point to dams’ negative effects on ecosystems and say that the human cost is not worth the potential benefits.

China is home to more than half of the world’s total dams, including the world’s largest and perhaps most controversial, the Three Gorges Dam. Vehemently criticized by geologists, environmentalists, biologists, and human rights activists alike, the 24 billion dollar project has long been defended by Chinese government officials. When it is complete, the government says, the dam will generate 18,000 megawatts of energy — eight times the amount of the Hoover dam.

But recently, fissures have appeared in the government’s previously unyielding position. As early as September 2007, speakers at a government-organized conference on the dam warned of “environmental catastrophe”. Wang Xiaofeng, deputy director of the government’s Three Gorges Project Construction Committee, told conference delegates: “We cannot profit from a fleeting economic boom at the cost of sacrificing the environment.”

The Zipingpu dam, the largest known to have sustained damage in the earthquake, was opened two years ago despite opposition from the Sichuan Seismological Bureau. In its objections, the government agency said that the dam was too close to a major fault line. Last year, Fan Xiao, an expert at the bureau, contended that more than a third of China’s dams are poorly constructed, calling them “time bombs waiting to go off in the event of flooding or other unexpected occurrences.”

In the wake of the recent disaster, it appears the warnings were well-founded. The State-run Xinhua News Agency reported “extremely dangerous” cracks in the dam and the collapse of the powerhouse and associated facilities. According to Aviva Imhoff, campaign director for the International Rivers Network, the unstable dam now poses a threat to millions of Sichuan residents as well as the Dujiangyan Irrigation System, a World Heritage Site just a few miles downstream from Zipingpu.

Fan Xiao has called for a government investigation into whether the dam contributed to the earthquake. “I have been concerned about the safety of these dams and reservoirs in the region since they were built,” he said. “I think we cannot rule out the possibility that building the Zipingpu Dam induced the earthquake because the epicenter is so close to the dam.”

According to the International Rivers Network, the recent developments are only the latest in the human and environmental cost incurred by the Zipingpu. The dam is situated on the Yangtze’s main tributary, the Minjiang River. Like many dammed and heavily polluted rivers in China, the Minjiang is reaching its ecological tipping point. A survey by biologist Deng Qixiang found that only 16 of the 40 species recorded in the 1950s still remain today.

Furthermore, in a 2007 report, Prime Minister Wen Jiabao said that the construction of the Zipingpu had displaced about 33,000 people. Nationally, 22.9 million people have been forcibly relocated from their homes to make way for dam projects.

Chinese officials have long promoted the projects as in the interest of the greater common good, fueling China’s booming economic development. Yet the price of the development is not exacted proportionally. “The must 
vulnerable and politically marginalized populations suffer most,” Director of the International Rivers Network Patrick McCully told MediaGlobal. Ethnic minorities and the poor constitute the majority of the displaced. “Dams tend
not to be built in areas where they would displace large numbers of 
politically well-connected people,” McCully said. “The more politically connected are better able to secure compensation payments and that compensation is often given to men as ‘heads-of-household’ rather than women.”

The conventional wisdom that hydropower dams are “clean”, nonpolluting sources of energy has also been put in question. The construction of large-scale dams, a process that, as in the case of the Three Gorges Dam, can take decades and produce massive carbon emissions. The degradation of watersheds and forests and the curtailment of the flow of organic carbon through rivers exacts its own environmental toll. In addition, according to McCully, dams are not sustainable in the long term, as they become blocked with silt and rendered ineffectual within a few decades of use.

While water scarcity is a real and pressing issue, many alternative water management strategies are already being successfully employed around the world. Small and seasonal dams, drip irrigation, and rain runoff water basins tend to be localized efforts and therefore more effective, responding to the specific needs of communities and ecosystems.

Meanwhile, no single source of energy is a solution to the global energy demand. A report by the World Commission on Dams, backed by the World Bank, proposes a comprehensive, participatory process to first evaluate needs for water, food and energy followed by a similarly participatory process to assess the full range of options. “In this assessment process,” the report says, “social and environmental aspects have the same significance as economic and financial factors.”