Launched in 1993, the dam has gone ahead despite complaints about its high cost and warnings of environmental damage, including the accumulation of silt and pollution in its 660-kilometer-long (410-mile-long) reservoir.

Officials claim it will provide huge benefits in flood control and energy generation. They say they can effectively deal with environmental hazards.

"In general, we have paid attention to these kind of problems and the government has taken various measures," Wang said. "I think we can handle this kind of problem properly."

China earlier this month announced it would move another 80,000 people this year from areas to be flooded by rising waters behind the dam.

The evacuees are among roughly 1.3 million moved to make way for the US$22 billion dam - the world's biggest project of its kind.

Mostly farmers, they will be resettled in newly built villages on high ground beside the dam, although many who have already moved have complained of a lack of farmland or other economic opportunities around their new homes.