While the dam has served as a barrier against seasonal flooding threatening the lower reaches of the Yangtze River and the electricity generated by hydropower has led to a decrease of 100 million tonnes of carbon emissions, the benefits have come at an ecological and environmental cost, officials said.
All the participants in a two-day forum held in Wuhan Tuesday agreed that the project had exerted a "notably adverse" impact on the environment of the Three Gorges reservoir, with a total circumference of 600 km, and along the Yangtze since last year, when the project began operation.
They said the huge weight of the water behind the Three Gorges Dam had started eroding the Yangtze's banks in many places, which, together with frequent fluctuations in water levels, had triggered a series of landslides.
"If no preventive measures are taken, the project could lead to catastrophe," they said.
Frequent geological disasters have threatened the lives of residents around the reservoir area, said Huang Xuebin, head of the headquarters for prevention and control of geological disasters in the Three Gorges Reservoir.
At the forum he described landslides around the reservoir that had produced waves as high as 50 meters, which crashed into the adjacent shoreline, causing even more damage.
Clear water discharged from the Three Gorges Dam has also threatened the safety of the protective embankments downstream, according to Hubei Vice Governor Li Chunming.
The open discussion of the negative effects of the Three Gorges Dam comes a month after the Wall Street Journal reported on the rising concerns of landslides, pollution and flooding in the area.
The participants in the forum in Wuhan also called for the establishment of a long-term mechanism on the prevention and control of geological disasters in the Three Gorges Reservoir Area, and a ban on fish farming in cages in the reservoir area to prevent an excess of nutrients degrading the water quality.