Chinese authorities have granted approval for an environmental assessment of a controversial 2 GW dam project — slated to be the country’s tallest dam — despite concerns voiced by a number of environmental groups.

The Ministry of Environmental Protection this week said it had approved a year-long assessment of the Shuangjiangkou project on the Dadu river in the southwestern Sichuan province.

Even as it gave the go-ahead, the Ministry acknowledged the project would “affect the spawning and movement of rare fish species, as well as the growth of endangered plants, including the Chinese yew, which is under first-class state protection”.The Ministry reasoned that countermeasures would help mitigate the impact. It called for protecting fish habitats and constructing seed banks for rare plants but did not say how it would enforce those measures.

The Shuangjiangkou dam will have an installed capacity of 2 GW and will generate 7.93 billion kilowatt-hours of power annually, according to the official Xinhua news agency. The project will cost $4 billion.

At 314 metres, it will be China’s tallest dam, surpassing the nearly 300-metre-tall Xiaowan dam on the Mekong river. The Shuangjiangkou dam will tower over the 180-metre-tall Three Gorges dam.

The green light for the dam follows recent approval granted to other controversial dam projects on the Brahmaputra, or Yarlung Tsangpo as it is known in Tibet, and the Nu river in Yunnan. The projects were listed in a new energy plan for 2011-15 announced in January, which included three new dams on the Yarlung Tsangpo. (http://thne.ws/VSCL8p).

Disappointment

Environmental groups have expressed disappointment over the moves. Green groups were encouraged by the government stepping in to stop projects in 2009 and 2010 over environmental concerns. The new energy plan, however, has been seen as reflecting a shift in the government’s stand, activists say.

The Shuangjiangkou dam, groups say, will not only adversely impact downstream flows but also submerge parts of at least six nature reserves.

“The chemical, thermal and physical changes that flowing water undergoes, when it is stilled, can seriously contaminate a reservoir or river downstream,” warned Liu Shukun, a professor at China Water Resources and Hydropower Institute, in an interview with China Daily.

While the public has until May 17 to put forward its views on the assessment, groups say inputs from the public have carried little weight in past projects. Hydropower groups are said to have close ties with local governments.

“Any project that poses such huge potential risk should only be completed with public approval,” Yang Yong, a geologist with the independent Hengduan Mountain Research Society, told China Daily.

“It’s important to let the public know how construction decisions are made.”