Three Gorges Dam Causes Downstream Erosion – Study

China’s Three Gorges Dam, the world’s largest hydropower project, is retaining huge amounts of sediment and nutrients and causing significant erosion in the downstream reaches of the Yangtze River, researchers have found.

In a paper published in the latest volume of the Geophysical Research Letters, Chinese scientists said the dam had retained 151 million tonnes of sediment each year since 2003.
“In response to this retention, significant erosion occurs in the riverbed downstream of the dam … Sediment flux to the Yangtze River mouth has decreased by 31 percent per year. The Yangtze delta is shrinking.

“Continued sediment retention at these rates, combined with more dams planned for the watershed, will severely affect people and the ecosystems on the Yangtze delta,” they added.

The paper gave no details nor estimates of how many people would suffer.

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