Dam proposal for Poyang Lake causes controversy

Some conservation groups were not convinced as to the merits of the proposed project. Zhu Laiyou, a senior water official in Jiangxi province, announced that the country's top scientists and ecologists had decided that a dam on Poyang Lake would do little harm to the environment or disrupt wildlife.

Poyang Lake is China's largest freshwater lake, covering 4,000 square kilometers. It is home to more than 300 species of birds and 120 species of fish. [Photo /  China Daily]

"Every conservationist knows that damming Poyang Lake in winter would be devastating to wetlands and migrating birds," Chen Kelin, director of Wetlands International China, said.

"Zhu's remarks made little sense. No water projects that disrupt river flow can be that perfect, can they?" Even the mere mention of the dam over the phone elicited a furious response from Chen.

Zhu, vice-director of Jiangxi's provincial water resources department, said six studies had concluded that the dam, on balance, would benefit the lake and the Yangtze River, and that it would not disrupt wildlife habitat.

"For instance, damming water in the dry season will help fish spawn," he told reporters in a group interview in late June.

Such conclusions soon reignited public wrangling over Jiangxi's plan to build the dam, because consent from scientists would carry weight with the central government.

Questions were raised about the independence and transparency of the studies. Some of those who led the research and others who reviewed it complained that the provincial government was trying to downplay the drawbacks of its water project.

They are urging the decision-makers to fully consider the scientific findings to avert future ecological disasters, especially at a time when China is still struggling to mend the woes of some of its large-scale hydro projects.

Lows last longer

A concept drawing of Poyang Dam, proposed by the Jiangxi government. [Photo/China Daily]

Covering an area of 4,000 square kilometers, Poyang is China's largest freshwater lake. So far it has escaped major industrial pollution, thanks to relatively slow economic development in Jiangxi.

The lake is fed by five rivers and connects to the lower reaches of the Yangtze. Lake waters flow into the Yangtze during dry seasons, while in the rainy seasons Poyang is replenished with floods. The yearly changes in water level also help maintain one of the most important wetlands in the world.

Poyang's dynamic ecosystem provides a unique and critical habitat for a variety of waterbirds, many of which are endangered species. About 98 percent of the world's Siberian cranes depend on the lake for survival each winter, according to the International Crane Foundation. It is also home to more than 120 species of fish and 300 species of birds.

Its precious near-natural state is now endangered by the province's plan to build a 2.8- km-wide dam with sluice gates across the narrowest part of the channel that links Poyang and Yangtze. The reason cited by the provincial government is that the lake and surrounding areas have suffered from low water levels almost every winter in the past decade.

"The seasonal decline in winter water level now starts earlier and lasts longer," said Wang Shengrui, who specializes in lake pollution control at the China Research Academy of Environmental Sciences. In an extreme case, parts of Poyang Lake turned into grassland in June as central China battled the worst drought in a century.

Changing climate patterns on the middle and lower reaches of the Yangtze, water storage behind the Three Gorges Dam, and increased water consumption by nearby communities are responsible for the frequent low water level, Wang said.

From 1952 to 2010, extremely low water levels (shallower than 8 meters) were recorded seven times. Six of them came after 2003, when the Three Gorges Dam started to hold back water for electricity generation, Wang said, citing official statistics.

Jiangxi government proposed building Poyang Dam in a plan to set up a Poyang Lake Eco-economic Development Zone, covering 51,200 square kilometers. The cost of the water project is estimated at 10 billion yuan ($1.5 billion).

'Push hard'

Fifteen academicians jointly wrote to Premier Wen Jiabao in September 2009 to express their concerns about the dam. Three months later, the central government approved the plan, but not the dam. The central government then asked the provincial government to make scientific assessments of the dam's likely impacts.

So Jiangxi invited some of the academicians who had opposed the plan, among others, to research six key aspects of the potential negative impacts of the dam, such as how it would change water quality, wetlands and migrating birds, and aquatic life in the lake.

The studies were supposed to provide scientific recommendations on whether the dam project should go ahead.

The reports were submitted in October 2010, but a comprehensive conclusion is yet to be completed. Meanwhile, Jiangxi water officials have actively pursued support from the water conservation, environmental protection and forestry ministries and related departments.