With an abundance of major waterways, hydropower is seen by many experts as the perfect way to improve the energy mix of a country in which 64 percent of its primary power comes from coal.

The attempted exploitation of this "clean energy", however, has been the source of much heated debate between governments, developers, power companies and environmentalists.

In the 1980s, the Gezhouba facility in Yichang, Hubei province, was the first hydro-electricity project to be built on the Yangtze River and cost almost 5 billion yuan (US$731 million). However, as well as boosting power supplies in the region, it also blocked the migration route of the Chinese sturgeon, a unique species that has lived in the Yangtze for more than 140 million years.

The fish used to swim upstream from the East China Sea to the river's upper reaches to spawn, but their numbers have been in steady decline since the erection of the Gezhouba plant, say scientists.

Hydropower projects on the Nujiang River, which runs from the Tibet autonomous region into Myanmar and Thailand, have caused stirs since 2003, when plans for a facility were halted after Chinese environmental groups objected.

The following February, Premier Wen Jiabao urged the relevant authorities to be prudent and ensure firms review the potential impact on the local ecology and communities before construction of a dam is approved.

His words were put into practice in 2005 when the State Environmental Protection Administration halted work on the Xiangjiaba and Xiluodu hydro-electricity projects on the Yangtze as full assessments had not been carried out beforehand.

The block was lifted last November, just days after the government unveiled its 4-trillion-yuan economic stimulus plan, which encouraged more infrastructure construction to spur growth.

This year, the Ministry of Environmental Protection put the brakes on two hydro projects on Jinsha River, a section connected to the upper Yangtze, after it was discovered developers had illegally started construction before an environmental review.

(China Daily August 13, 2009)