Jiangxi Province’s proposed plan to build a dam at Poyang Lake to “offset the negative impact of the Three Gorges Dam” sounds like a great idea to save the lake, but it may end up creating bigger problems for the entire Yangtze river system.
When the worst drought for 50 years hit in May, Poyang Lake, China’s biggest freshwater lake, shrank to only 13 percent of its size last year.The Three Gourges Dam was believed by many to be contributing to the severity of drought.
As one of China’s most important ecological protection areas and a major world ecological zone approved by the World Wide Fund for Nature, Poyang Lake functions as a natural moderator in water storage, flood control, climate change and pollutant degradation.
The local government says that a Poyang dam will be used for flood prevention, shipping, combating drought, and other functions.
But it is also worried that building a dam will have disastrous consequences for the lake’s ecological environment.
Dam construction runs the risk of reducing water quality, breeding blue algae and decreasing the wetland value of the lake, to name just a few.
It is not just a problem for Jiangxi, but also one for the entire nation.
As a matter of fact, some have labeled the idea of constructing the dam “selfish,” as they argue that it will put more pressure on the Yangtze, reducing water levels for cities further downriver.
As a means of changing nature, water conservancy projects are often controversial.
Even though the Three Gorges Dam went through tough revisions and repeated debate before becoming operational, problems are still surfacing now, followed by criticism that engineers failed to consider the full impact it would have on the environment during its early design period.
The proposed Poyang dam had better learn this lesson and proceed even more cautiously.
When many other countries are turning away from dam construction, China is busy building more.
According to media reports, more than 100 large hydroelectric stations have been built along the Yangtze. Now, only the Poyang and Dongting lakes are connected to the Yangtze, without being interrupted by dams.
Any movement toward the large-scale change of nature should be backed up by adequate scientific proof as to its benefits.
When the damage is done, it is often irreversible.