A passenger ship sails in the Bawu Gorge of the Small Three Gorges in the lower reaches of the Daning River, in central China, with maple leaves as the foreground, on Nov. 30, 2007.

The Three Gorges Dam project on the Yangtze River has played an irreplaceable role in flood control on the Yangtze River and in protecting the area's ecological environment, experts have said.