Friday, August 24, 2012

Three Gorges Dam

Hydropower In Nepal

Three Gorges Dam
The Three Gorges Dam is the world's largest power station in terms of installed capacity (22,500 MW) .... As well as producing electricity, the dam is intended to increase the Yangtze River's shipping capacity and reduce the potential for floods downstream by providing flood storage space. The Chinese government regards the project as a historic engineering, social and economic success, with the design of state-of-the-art large turbines, and a move toward limiting greenhouse gas emissions. However, the dam flooded archaeological and cultural sites and displaced some 1.3 million people, and is causing significant ecological changes, including an increased risk of landslides. The dam has been a controversial topic both domestically and abroad. ...... A large dam across the Yangtze River was originally envisioned by Sun Yat-sen in The International Development of China, in 1919. He stated that a dam capable of generating 30 million horsepower (22 GW) was possible downstream of the Three Gorges. ........ On completion, the reservoir flooded a total area of 632 square kilometres (244 sq mi) of land ..... Full cost recovery is expected to occur ten years after the dam starts full operation ...... The dam was expected to provide 10% of China's power. However, electricity demand has increased more quickly than planned. Even fully operational, on average, it supports only about 1.7% of electricity demand in China in the year of 2011 ...... At full power, Three Gorges reduces coal consumption by 31 million tonnes per year, avoiding 100 million tonnes of greenhouse gas emissions, millions of tonnes of dust, one million tonnes of sulfur dioxide, 370,000 tonnes of nitric oxide, 10,000 tonnes of carbon monoxide, and a significant amount of mercury. Hydropower saves the energy needed to mine, wash, and transport the coal from northern China. ....... From 2004 to 2007 a total of 198 million tonnes of goods passed through the ship locks. ..... sedimentation projections are not agreed upon, and the other is that the dam sits on a seismic fault. ..... China's huge reforestation effort. This accelerated after severe flooding in 1998 convinced the government that it must restore tree cover, especially in the Yangtze's basin upstream of the Three Gorges Dam ..... home to 6,388 species of plants, which belong to 238 families and 1508 genera. Of these plant species, 57 percent are endangered. These rare species are also used as ingredients in traditional Chinese medicines ....... the Yangtze River basin is home to 361 different fish species and accounts for twenty-seven percent of all endangered freshwater fish species in China ..... The reservoir's flood storage capacity is 22 cubic kilometres ... This capacity will reduce the frequency of major downstream flooding from once every ten years to once every 100 years. The dam is expected to minimize the effect of even a "super" flood ....... Since the filling of the reservoir in 2003, the Three Gorges Dam has supplied an extra 11 cubic kilometres of fresh water to downstream cities and farms during the dry season .... The installation of ship locks is intended to increase river shipping from ten million to 100 million tonnes annually, as a result transportation costs will be cut between 30 and 37%. Shipping will become safer, since the gorges are notoriously dangerous to navigate. Ships with much deeper draft will be able to navigate 2,400 kilometres (1,500 mi) upstream from Shanghai all the way to Chongqing. It is expected that shipping to Chongqing will increase fivefold
China's Three Gorges Dam: An Environmental Catastrophe?
For over three decades the Chinese government dismissed warnings from scientists and environmentalists that its Three Gorges Dam—the world's largest—had the potential of becoming one of China's biggest environmental nightmares. But last fall, denial suddenly gave way to reluctant acceptance that the naysayers were right. ..... When complete, the dam will generate 18,000 megawatts of power—eight times that of the U.S.'s Hoover Dam on the Colorado River. .... "There's been a lot less rain, a lot more drought, and the potential for increased disease" ..... "When it comes to environmental change, the implementation of the Three Gorges dam and reservoir is the great granddaddy of all changes." ..... Inhabited for several millennia, the Three Gorges region is now a major part of western China's development boom. To date, the government has ordered some 1.2 million people in two cities and 116 towns clustered on the banks of the Yangtze to be evacuated to other areas before construction, promising them plots of land and small stipends—in some cases as little as 50 yuan, or $7 a month—as compensation. ....... The first of the Yangtze's famed gorges—a collection of steep bluffs at a bend in the river—was determined to be the perfect site. ...... a narrow lake 410 miles (660 kilometers) long—60 miles (97 kilometers) longer than Lake Superior ..... the landslides are directly linked to filling the reservoir. Water first seeps into the loose soil at the base of the area's rocky cliffs, destabilizing the land and making it prone to slides. ..... One of the greatest fears is that the dam may trigger severe earthquakes, because the reservoir sits on two major faults: the Jiuwanxi and the Zigui–Badong. ...... officials failed to foresee the full magnitude of the dam's effects ..... half of China's animal and plant species, including the beloved giant panda and the Chinese sturgeon, are found no where else in the world. The Three Gorges area alone accounts for 20 percent of Chinese seed plants—more than 6,000 species. ..... Downstream, near where the river empties into the East China Sea, the land around the Yangtze contains some of the densest clusters of human habitation in the world, and overfishing there has already endangered 25 of the river's 177 unique fish species. ..... When officials unveiled plans for the dam, they touted its ability to prevent floods downstream. Now, the dam seems to be causing the opposite problem, spurring drought in central and eastern China. ..... the dam had reduced the flow volume of the river by 50 percent. To make matters worse, China is now plowing ahead with a controversial $62-billion scheme to transfer water from the Yangtze to northern China, which is even more parched, through a network of tunnels and canals to be completed by 2050. ..... "Once you dramatically change the climate and change water patterns, as is now seen in the Three Gorges region," he says, "you change a lot of environmental variables. Almost all infectious diseases are up for grabs." ..... President Hu Jintao and Premier Wen Jiabao are eager to distance themselves from a project they inherited. ..... Government officials fear that continued free discussion of the project's ramifications could lead to civil unrest. ..... China still draws 82 percent of energy from coal, but large dams are crucial to the country's climate change program, which aims to increase its proportion of electricity from renewable resources from the current 7.2 percent to 15 percent by 2020. Over one third of that will come from hydropower—more than from any other source. Twelve new dams are planned for the upper Yangtze alone. ..... [a river] is also important for shipping, alleviating pollution, sustaining species and ecosystems, and maintaining a natural evolutionary balance." .... "The Yangtze doesn't belong to the Three Gorges Project Development Corporation," Fan adds. "It belongs to all of society."
China's Three Gorges Dam
a dam one and a half miles wide and more than 600 feet high that will create a reservoir hundreds of feet deep and nearly 400 miles long ..... the dam's hydropower turbines are expected to create as much electricity as 18 nuclear power plants. .... the largest construction project in China since the Great Wall. Many high-ranking Chinese officials expect the dam to become a potent symbol of their nation's vitality in the new century and the new millennium. ..... authorities hope the dam will take care of several major national problems with a single monumental stroke. .... The Yangzi's notorious floods have been recorded for millennia and have claimed more than 1 million lives in the past 100 years. ..... Officials hope the combination of inexpensive electricity and cheap river transportation will further open the region to international investment -- making Chongqing a major business center. .... Allegations of corruption among officials involved with the project have raised fears of shoddy construction. The Chinese media recently reported several incidents in which corruption and poor construction have led to disasters at major building projects. Notable among the reports was the collapse of a steel bridge in the city of Chongqing in January 1999 that killed 40 people. ..... Li Peng, the former Chinese premier and Soviet-trained engineer who spearheaded the dam's construction. .... The dam will "drown" more than 100 towns once the water starts to rise in 2003. .... Archaeologists and historians have estimated nearly 1,300 important sites will disappear under the reservoir's waters ..... More than 20,000 workers are working around the clock on the dam itself.
Great Wall Across The Yangtze
Swimming Great plans are afoot: A bridge will fly to span the north and south, Turning a deep chasm into a thoroughfare; To hold back Wushan's clouds and rain Till a smooth lake rises in the narrow gorges. The mountain goddess if she is still there Will marvel at a world so changed. - poem by China's former Communist Leader Mao Tse-tung The Three Gorges project has been engineered to store over 5 trillion gallons of water and to withstand an earthquake of 7.0 on the Richter scale. The reservoir will allow 10,000-ton freighters to enter the nation's interior, which currently limits access to boats under 1,500 tons. In addition to increasing commercial shipping access to China's interior, the government says the dam will control devastating floods and provide much-needed electrical power to China's growing cities. .... Like China's Great Wall, it will be one of the few man-made structures visible from space.
Biggest flood peak passes Three Gorges Dam
As the world's largest water hydropower project, the Three Gorges Project consists of a dam, a five-tier ship dock and a total of 32 hydropower turbo-generators.
China Admits Problems With Three Gorges Dam
The Three Gorges Dam, the world’s largest hydroelectric project and a symbol of China’s confidence in risky technological solutions, is troubled by urgent pollution and geologic problems, a high-level government body acknowledged. ..... According to official figures, the venture cost China about $23 billion, but outside experts estimate it may have cost double that amount. The dam has been plagued by reports of floating archipelagoes of garbage, carpets of algae and landslides on the banks along the vast expanse of still water ..... the government has fallen far short of its goals in helping to resettle the 1.4 million people displaced by the rising waters behind the dam. ..... denied that the project played any role in China’s powerful May 2008 quake in Sichuan Province, in which at least 87,000 people died. .... Faced with a historic drought this spring, cities downstream of the dam have been unable to accommodate oceangoing vessels that usually visit their ports, and about 400,000 residents of Hubei Province lost access to drinking water this month. ..... the dam has changed regional water tables, contributing to the shortage. .... some problems were anticipated during the dam’s construction, but that others “arose because of new demands posed by economic and social development.” .... “My sense is that the Chinese government is getting better and better at collecting information about things like this.”
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