The last unit of the 6X550MW hydroelectric generating turbines went into operation in early December 1999 at the Ertan hydro power station in China’s Sichuan Province. The project includes a 200m parabolic double curvature arch dam, two diversion tunnels and a mechanical log passing facility with an annual capacity of 1.1M m3. Ertan supplies electricity to the Yalong river region in southwest China.