|Case Study: The Three Gorges Dam|
For a long time, building dams has been an effective way to harness water for human use. Recently, however, it has become clear that the consequences of our reliance on dams are mixed. A good example is the controversial Three Gorges Dam on the Yangtze River in China.
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For much of the 20th Century, dam projects were seen as cost-effective ways to increase energy availability, harness and provide clean water, and control flooding, while also providing jobs and economic growth. Dams were the preferred way to:
Today new dams no longer seem so appealing.
There are currently 50,000 plus large dams in the world. It is unlikely that many more will be built, since in the 21st Century the logistical, human, and ecological costs would in all probability outweigh the benefits.
In no place has the concern over dam projects generated more publicity than in China, home to many of the world’s medium and large-sized dams. Included on China’s list is the recently completed Three Gorges Dam, the world’s largest hydroelectric project. The Three Gorges Dam is part of a concerted effort by the Chinese to tap into the many rivers draining out of the Tibetan high plateau to meet the country’s ever growing energy needs.
While initially the Chinese government proudly emphasized the engineering marvel that was represented by the dam, it has become increasingly evident that the dam has taken a staggering social and cultural toll. It is estimated that 1.3 million people were forced into resettlement during construction, with up to 4 million more anticipated to be relocated in the next 15 years due to environmental damage (primarily landslides) and pollution from the project. Entire communities, ways of life, and ancestral archives have been flooded and/or destroyed. Fears are rising that a natural disaster, such as an earthquake, could cause immense damage to the dam, and potentially kill millions in a resulting flood.
The environmental toll has been no less significant; the litany of effects described above for dams has occurred on an unprecedented scale. Ecosystem destruction and pollution has occurred not only at the site of the dam, but also in communities where large populations have had to relocate and further stress natural balances in regions already suffering from overpopulation. As farmers retreat to higher ground and attempt to build farms on the hillsides, massive erosion and landslides are occurring. Geologists believe that the threat of earthquakes, already a risk in this region, is increased by the pressure from the water in the dam’s growing reservoir. Silt accumulation in the reservoir is developing rapidly, and is expected to cause flooding upstream.
The problems created by the Three Gorges Dam have clearly demonstrated that large dam projects are not the solution they were once thought to be. Alternative methods of energy generation more suited to modern life and environmental realities must be developed; these will undoubtedly be more technologically creative, more local, and less environmentally destructive.
New York Times' "Chinese Dam Projects Criticized for Their Human Costs"
BBC News' "In Pictures: Three Gorges Dam"
BBC News' "Three Gorges Dam Reaches for the Sky"
BBC News' "Deep Concern Over Three Gorges Dam"