Dams May Degrade One of China's Remaining Healthy Rivers

By Rachel Cernansky | May 22, 2009 11:34 am

dam1.jpgChina’s plan to build dams along the Mekong River poses the greatest threat to the river’s future, according to a United Nations report released yesterday. China is constructing a series of eight dams on the upper half of the Mekong as it passes through high gorges of Yunnan Province, including the recently completed Xiowan Dam, which — at 958 feet (292 meters) high — is the world’s tallest. Its storage capacity is equal to all the Southeast Asia reservoirs combined [AP], according to the report.

The Mekong, which is known as the Lancang in China, is an important source of water, food, and jobs for residents in the river basin, and runs through China, Myanmar, Laos, Thailand, Cambodia and Vietnam. It provides a habitat for rare species of bird and marine life. If the dams move ahead, said the report, the consequences will include “changes in river flow volume and timing, water quality deterioration and loss of biodiversity” [AP]. But Chinese Foreign Ministry spokesman Ma Zhaoxu defended the proposed plans, saying China would give equal attention to hydropower development on transnational rivers and ecological protection [Xinhua].

The UN report also looks at the Nu River, for which there are controversial plans to construct 13 dams. Together, the dams would generate more power than the Yangtze River’s Three Gorges Dam, but some residents oppose the plans because they do not want to move or say they would not be compensated fairly if they were to do so. The dams also face resistance from countries downstream and from the UN heritage body Unesco, which fears the dams would endanger a world heritage site recognised in 2003 and covering the headwaters of the Nu, Mekong and Yangtze rivers [Times Online].

The Mekong and its tributaries have already been degraded by pollution and climate change, and water levels in the northern section have dropped as a result of earlier dam projects—but none of these problems have reached alarming levels, said the report. On the whole, the river can withstand some additional pressure from agricultural or industrial demand, but the report identified several particular river basins as threatened. “The time to tackle these challenges is now, otherwise the projected growth and development may impact on the basin’s ability to meet future water needs” [AP], said the UN’s Young-Woo Park.

Related Content:
80beats: Did a New Hydropower Dam Trigger China’s Deadly 2008 Earthquake?
80beats: 1/3 of China’s Yellow River Not Even Fit for Industrial Use

Image: Flickr / kenner116

CATEGORIZED UNDER: Environment, Living World
MORE ABOUT: China, rivers, water
  • Julian

    But what about the catfish, man?!

  • p

    Too bad the people who it’s going to affect don’t have a say in things.

  • Chris TMC

    Dams here in the USA caused the same kinds of problems.
    We did not know/care about the loss of biodiversity and displacing people when our nation developed in this way.

  • johnn costello

    Will the end justify the means????

  • http://DiscoverBlogs Black Feather

    Not a good idea. I always felt the Three Gorges Dam caused problems that are not apparent because no one is making a link between the dam and some catastrophes that occur in other parts of the World. Seems to me holding back that much water has to affect another part of the biosphere somehow. Water does much more than flow just as trees do more than make a place pretty. We all learned the water cycle science in junior high school. What do they teach engineers? I live in Texas where developers don’t understand trees are the lungs of the Earth and so they cut them all down to make as many mini malls, house, highway as possible… the temperatures increase and we get less rain. The dried trees that pile up leave us open for wildfires . I recently read a news article where developers actually piled a large amount of cut down trees that had been cleared for housing at the foot of a park. Its all about the money and less about thinking of the possibilities for future problems created from these decisions. I hope I’m wrong about the dams but, its looks like a disaster in the making. What if?? should be the question before doing balancing acts with Nature.


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