China's Yangtze River, Three Gorges Dam upon completion, will be the largest hydroelectric complex in the world. It is located in China's rural heartland on the third largest river in the world, the Yangtze. The Three Gorges Dam towers 182 meters (600ft) high and stretches over 2.4 kilometers (1.5miles). The reservoir created by the dam will extend nearly 400 miles upstream. The project consists of a river dam, spillway structures, powerhouse, and buildings for navigation.
The dam's construction will take 17 years and has been divided into three phases. The first phase dealt with preparations for construction of the dam. The diversion channel was built so that the river could be blocked. The second phase mainly focused on construction of the spillway, left bank power houses, and ship's locks. The first batch of generators started producing power during this phase. The third phase involves construction of the right bank's powerhouse, which will be the completion of the entire project.
The Three Gorges hydroelectric power plant contains 26 turbine generator units. Currently the generated electricity is being sent to Central and East China, Guangdong, and Chongqing. It is predicted that over one-ninth of China's electrical power will be created at the Three Gorges Dam.
The idea for the dam was first proposed by Dr. Sun Yetsen in 1918, and has been under consideration ever since. The Three Gorges Dam is a marvel of engineering, and the greatest challenge its designers have ever faced. The dam has been designed to store over 5 trillion gallons of water and to withstand an earthquake of 7.0 on the Richter scale. Ocean-going vessels of over 10,000 tons will now be able to enter the nation's interior, which will redefine how products and technology move around China.
The three gorges dam not only creates electricity, but will also control the annual floods that have devastated vast portions of China for millennia. Each year 15 million people and 1.5 million hectares of farmland will be protected from flood threats, thanks to the Three Gorges Dam.
The Three Gorges Dam project will not only fulfill its utilitarian needs, but will also serve as a symbol of pride for the Chinese people.
The Impact of the Dam
The final effect of the dam on river control is disputed. For more than 600kilometres (372 Yangtze rivermiles) upstream the Yangtze will become more lake than river, but many experts argue that a slower flow rate will lead to an even more rapid build-up of silt, especially against the dam itself, causing floods to flow over the top of it. Some say more effective flood control would be provided by replacing the more than 800 lakes, vital for storing and dispersing flood waters, which have disappeared beneath unchecked urban expansion. Despite impressive forecasts for electricity generation, some argue that a series of smaller dams would have been more cost--effective, less dangerous and more productive.
The dam is only part of a larger project to alleviate poverty in rural areas, which until now have relied almost solely on the river for transport. Local governments have been working to attract fresh investment to soak up surplus agricultural labor, and new roads and railway Iines are being built, with new bridges across the gorges of Yangtze tributaries.
Compensation of 40 billion yuan (about US$4.82 billion) has been allocated for those forced to move--as much as 3000 yuan per head in some small towns where average annual incomes are as little as 1500 yuan (US$l80). Nevertheless the mass forced Relocation has attracted widespread criticism. Relocation projects are running well behind schedule, and Chinese sociologists have criticized poor planning, falsified figures, corruption and inadequate resources.
The Environmental Impact
The environmental impacts of the project are profound, and are likely to get worse as time goes on. The submergence of hundreds of factories, mines and waste dumps, and the presence of massive industrial centers upstream are creating a festering bog of effluent, silt, industrial pollutants and rubbish in the reservoir. Erosion of the reservoir and downstream riverbanks is causing landslides, and threatening one of the world’s biggest fisheries in the East China Sea. Scientists estimate that annual catches may be reduced by one million tons due to the decline in fresh water and sediment reaching the sea.
The Three Gorges Dam is a model for disaster, yet the Chinese government is replicating this model both domestically and internationally. Within China, huge hydropower cascades have been proposed and are being constructed in some of China’s most pristine and biologically and culturally diverse river basins - the Lancang (Upper Mekong) River, Nu (Salween) River and upstream of Three Gorges Dam on the Yangtze River and tributaries. Internationally, Chinese banks and companies are involved in constructing dozens of large dams, particularly in Africa and Southeast Asia.
While Three Gorges is the world’s biggest dam, the problems at Three Gorges are not unique. Around the world, large dams are causing social and environmental devastation while better alternatives are being ignored.
The dam's construction will take 17 years and has been divided into three phases. The first phase dealt with preparations for construction of the dam. The diversion channel was built so that the river could be blocked. The second phase mainly focused on construction of the spillway, left bank power houses, and ship's locks. The first batch of generators started producing power during this phase. The third phase involves construction of the right bank's powerhouse, which will be the completion of the entire project.
The Three Gorges hydroelectric power plant contains 26 turbine generator units. Currently the generated electricity is being sent to Central and East China, Guangdong, and Chongqing. It is predicted that over one-ninth of China's electrical power will be created at the Three Gorges Dam.
The idea for the dam was first proposed by Dr. Sun Yetsen in 1918, and has been under consideration ever since. The Three Gorges Dam is a marvel of engineering, and the greatest challenge its designers have ever faced. The dam has been designed to store over 5 trillion gallons of water and to withstand an earthquake of 7.0 on the Richter scale. Ocean-going vessels of over 10,000 tons will now be able to enter the nation's interior, which will redefine how products and technology move around China.
The three gorges dam not only creates electricity, but will also control the annual floods that have devastated vast portions of China for millennia. Each year 15 million people and 1.5 million hectares of farmland will be protected from flood threats, thanks to the Three Gorges Dam.
The Three Gorges Dam project will not only fulfill its utilitarian needs, but will also serve as a symbol of pride for the Chinese people.
The Impact of the Dam
The final effect of the dam on river control is disputed. For more than 600kilometres (372 Yangtze rivermiles) upstream the Yangtze will become more lake than river, but many experts argue that a slower flow rate will lead to an even more rapid build-up of silt, especially against the dam itself, causing floods to flow over the top of it. Some say more effective flood control would be provided by replacing the more than 800 lakes, vital for storing and dispersing flood waters, which have disappeared beneath unchecked urban expansion. Despite impressive forecasts for electricity generation, some argue that a series of smaller dams would have been more cost--effective, less dangerous and more productive.
The dam is only part of a larger project to alleviate poverty in rural areas, which until now have relied almost solely on the river for transport. Local governments have been working to attract fresh investment to soak up surplus agricultural labor, and new roads and railway Iines are being built, with new bridges across the gorges of Yangtze tributaries.
Compensation of 40 billion yuan (about US$4.82 billion) has been allocated for those forced to move--as much as 3000 yuan per head in some small towns where average annual incomes are as little as 1500 yuan (US$l80). Nevertheless the mass forced Relocation has attracted widespread criticism. Relocation projects are running well behind schedule, and Chinese sociologists have criticized poor planning, falsified figures, corruption and inadequate resources.
The Environmental Impact
The environmental impacts of the project are profound, and are likely to get worse as time goes on. The submergence of hundreds of factories, mines and waste dumps, and the presence of massive industrial centers upstream are creating a festering bog of effluent, silt, industrial pollutants and rubbish in the reservoir. Erosion of the reservoir and downstream riverbanks is causing landslides, and threatening one of the world’s biggest fisheries in the East China Sea. Scientists estimate that annual catches may be reduced by one million tons due to the decline in fresh water and sediment reaching the sea.
The Three Gorges Dam is a model for disaster, yet the Chinese government is replicating this model both domestically and internationally. Within China, huge hydropower cascades have been proposed and are being constructed in some of China’s most pristine and biologically and culturally diverse river basins - the Lancang (Upper Mekong) River, Nu (Salween) River and upstream of Three Gorges Dam on the Yangtze River and tributaries. Internationally, Chinese banks and companies are involved in constructing dozens of large dams, particularly in Africa and Southeast Asia.
While Three Gorges is the world’s biggest dam, the problems at Three Gorges are not unique. Around the world, large dams are causing social and environmental devastation while better alternatives are being ignored.
No comments:
Post a Comment