One year after the completion of the Three Gorges Dam across China's Yangtze River, the Chinese government has admitted that the world's largest hydroelectric project is having a disastrous impact on the environment. Claudia Blume reports from VOA's Asia News Center in Hong Kong.

Navigation trial at the Three Gorges Dam, 30 April 2007

The Three Gorges Dam has always been steeped in controversy. Since construction began in 1993, the project has been criticized for uprooting more than a million people and causing the destruction of towns and villages. Scientists and activists warned that the project was an ecological disaster waiting to happen.

The Chinese government, however, ignored the criticism. Former leaders Jiang Zemin and Li Peng promoted the world's largest hydroelectric dam as a cure for the devastating floods on the Yangtze River, and an important source of clean energy for the country's booming economy.

Now, only a year after its completion, Chinese officials have admitted that the project is causing severe ecological problems. On Wednesday, they said the results could be a "catastrophe."

Weng Lida is and environmental scientist in Wuhan and the former head of the Yangtze River Water Resources Protection Commission. He says one problem is that the weight of water behind the dam has led to erosion of the river's shores, causing landslides.

"That means in the reservoir area, also the downstream area, we have to pay much attention to the stability of the riverbank to avoid this kind of damage caused by landslides, because this will destroy property and lives," he said.

State media reported this week that the shore of the reservoir had collapsed in 91 places and that a total of 36 kilometers had caved in. Official reports said that landslides in the reservoir produced waves as a high as 50 meters, which crashed into the shoreline and caused damage.

Weng says another problem is that the water quality has deteriorated, especially in the tributaries of the Yangtze, where outbreaks of algae have become common.

Beijing-based environmental activist Dai Qing is one of China's most vocal opponents of the dam. She says the situation has become so bad that authorities have no choice but to admit the problems.

"If the authorities of the Three Gorges project just like before say: 'Everything is great, everything is good', and then one day something happens, you can not cover it - who will take responsibility? I think he thinks - no way to 100 percent cover the problem, and then it is better to announce it," she said.

Senior officials warned Wednesday that China could face a catastrophe if the environmental problems at the Three Gorges Dam are not addressed as quickly as possible.