The Xiaowan Dam is a large hydroelectric arch dam

Arch dam

An arch dam is a type of dam that is curved and commonly built with concrete. The arch dam is a structure that is designed to curve upstream so that the force of the water against it, known as hydrostatic pressure, presses against the arch, compressing and strengthening the structure as it pushes...

 on the Lancang (Mekong) River

Mekong

The Mekong is a river that runs through China, Burma, Laos, Thailand, Cambodia and Vietnam. It is the world's 10th-longest river and the 7th-longest in Asia. Its estimated length is , and it drains an area of , discharging of water annually....

 in Yunnan Province

Yunnan

Yunnan is a province of the People's Republic of China, located in the far southwest of the country spanning approximately and with a population of 45.7 million . The capital of the province is Kunming. The province borders Burma, Laos, and Vietnam.Yunnan is situated in a mountainous area, with...

, southwest China. It is the world's highest arch dam and will be the second largest hydroelectric power station in China after the Three Gorges Dam

Three Gorges Dam

The Three Gorges Dam is a hydroelectric dam that spans the Yangtze River by the town of Sandouping, located in the Yiling District of Yichang, in Hubei province, China...

. Construction started on 1 January 2002. The river was dammed in October 2004. The first generator was commissioned in September 2009 and the dam was complete in March 2010.

Specifications

Xiaowan Dam is the highest arch dam in the world with height of 292 m (958 ft). It creates a 15000000000 cubic metre reservoir with an area of more than 190 square kilometre. The hydroelectric power station will eventually consist of six generating units with generating capacity of each. The total generating capacity of the project will be . The first generator went into operation in September 2009 and the last one is expected in 2013. The cost of the Xiaowan hydropower station is estimated at ¥32 billion (nearly US$

United States dollar

The United States dollar , also referred to as the American dollar, is the official currency of the United States of America. It is divided into 100 smaller units called cents or pennies....

3.9 billion). The hydroelectric power station is being constructed and operated by Huaneng Power International

Huaneng Power International

Huaneng Power International Inc. , or Huaneng, was established in 1994 administrated by the State Council of the People's Republic of China. It is one of the five largest power producers in China. It engages in the development, construction and operation of large power plants...

.