A mighty big river runs through this one. China Three Gorges Corporation operates the world's largest hydropower project -- the Three Gorges on the Yangtze River. Located near the Xilingxia gorge, a 185-meter-high project dam controls a drainage area of 1 million sq. km. and an average annual runoff of 451 billion cu. meters. The Three Gorges project has a five-tier ship lock and more than 25 hydropower turbogenerators. Subsidiary China Yangtze Power was set up in 2002 to manage two power plants, Gezhouba and Three Gorges. Four more hydropower plants at Xiluodu, Xiangjiaba, Wudongde, and Baihetan are under construction and expected to become operational in 2013.