A scientific study has found that the Three Gorges Dam, the world’s largest hydropower project, has not contributed to climate change, according to a report by Xinhua, the Chinese state news agency.
The study, published by the Social Sciences Academic Press under the Chinese Academy of Social Sciences, focused on climate change and found that the dam’s environmental impact was limited to a 12-mile radius, the Xinhua article said.
“No direct link has been found between the dam and local severe droughts and floods in recent years, according to the report, which instead laid the blame on extreme weather conditions caused by abnormal atmospheric circulation and air temperature mainly incurred by changes in ocean temperature and snow conditions at the Qinghai-Tibet Plateau,” according to the article, which was published Friday.
The results of the study were the first to be released publicly since controversy over the dam has grown this year. Critics of the dam and some Chinese news organizations raised questions in the spring about whether the dam had worsened the effects of a drought that hit the Yangtze River region of central and southern China. The Three Gorges Dam stands in the middle of the Yangtze River.
The newspaper Shanghai Daily reported in early June that an official in the drought relief and flood control bureau said that the dam’s planners had failed to gauge its impact properly.
The official, Wang Jingquan, said that water levels in two lakes downstream from the dam, Dongting in Hunan Province and Poyang in Jiangxi Province, had fallen, in part because of the storage of water in the reservoir behind the dam.
In May, two Chinese officials warned of “urgent problems” associated with the dam.
The drought was the worst in the region in 50 years, and water levels in the Yangtze and bodies of water linked to it fell drastically. This led to greater scrutiny of the dam. On the Internet, many Chinese asked whether the dam was at least partly responsible for the drought. Several scientists, including at least one American, said then that there was no evidence that the dam had caused the drought. Rainfall in early June began to alleviate the drought.
The Xinhua report on Friday said the recent study, called “Green Book of Climate Change: Annual Report on Actions to Address Climate Change,” recommended that “the authorities strengthen monitoring, evaluation and research of the climate condition in regions around the dam.”
The drought this year also raised questions about another ambitious water project, the South-North Water Diversion, which will cost $62 billion. Chinese leaders aim to transfer at least six trillion gallons of water a year via canals from the Yangtze and its tributaries to cities in the north, where droughts are much worse than in the center and the south.
The middle route of the project, which starts at the Danjiangkou Reservoir in Hubei Province, is expected to begin operating in 2014. The eastern route, which runs alongside the ancient Grand Canal, is expected to be operational by 2013. Critics say the government has not done enough studies to determine the project’s impact on waterways in the south.
