4CM+Pros+and+Cons

4CM Pros and Cons
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Pros: 1.Controls flooding and provides recreational activities such as boating fishing and swimming, if the lake is not being used for drinking water. 2. It also controls river traffic, floods and provides clean electricity. 3.Before the dam was created, the Chinese uses coal, but now since the dam is built, they don't use it anymore. 4. The dam has made many people happy so there would be no more floods. 5. It provides a lot of work for a lot workers. 6. It made the Chinese famous because the dam is the biggest dam in the world.

Cons: 1.Disrupts natural seasonal changes in he river, and ecosystems can be destroyed. 2.Ends flooding that help to clean out the silt in rivers, causing them to clog (Energy Laboratory). 3.The silt that usually flows down to the Beaches and Estuaries is block by the dam. 4.Studies show that the plant decay caused downstream of major dams produces as many greenhouse gasses as more conventional methods of producing electricity. 5.Dams are expensive to build, and due to drought may become useless, or produce much less power than originally planned. 6.Dams can break in a massive flash flood 7.The dam body was completed in 2006. Except for a ship lift, all of the originally planned components of the project were completed on October 30, 2008 when the 26th generator was brought into commercial operation. Currently, it contains 26 completed generators in the shore power plant, each with a capacity of 700 MW. Six additional generators in the underground power plant are being installed and are not expected to become fully operational until around 2011. 8.Coupling the dam's 32 main generators with 2 smaller generators (50 MW each) to power the plant itself, the total electric generating capacity of the dam will eventually reach 22,500 MW. The project produces hydroelectricity, increases the river's navigation capacity, and reduces the potential for floods downstream by providing flood storage space. 9.From completion until September 2009 the dam has generated 348.4 TWh of electricity, covering more than one third of its project cost. 10.Giant dams are costly engineering marvels that are built for expected benefits to humans or their political leaders, but they also have negative effects which sometimes outweigh the positive ones. 11. The Three-Gorges Dam under construction on China's Yangtze River is a case in point. It will be one of the largest dams ever built; 1.3 miles wide and 607 feet high, and its reservoir will be 370 miles long. 12.The dam's positive effects are: It would prevent the recurrent catastrophic floods that have devastated China's major agricultural breadbasket for several millennia by providing a steady flow-velocity and discharge-volume of water along the Yangtze's 800 miles below the dam to Shanghai and the sea. Its reservoir will provide needed water for farms and cities during drought periods. 13.Its 26 turbines would generate 18,200 megawatts of electrical energy, the equivalent of 18 nuclear power plants -- more than any other dam in the world. The reservoir's shoreline would spawn a recreational boating and fishing industry, and less dredging of silt would have to be done in Shanghai's harbor. 14.The dam's negative effects are: Roughly 2 million people would be displaced from their villages, and farms would be submerged (along with thousands of archeological sites) under the reservoir's water and silt. 15.The Yangtze's tremendous silt load (530 million tons/year, the fourth largest of all world rivers) would end up in the reservoir behind the dam, which would steadily decrease its water-storage and electrical-generation capacity and which could render the dam useless within 150 years (unless expensive silt-dredging and disposal is done continuously). Chungking's major harbor, 1,200 miles upstream from the sea and now kept silt-free by the Yangtze's fast current, could (unless dredged vigorously) lose its marine shipping when it fills with delta sediments at the head of the new reservoir's placid waters. 16.China's coastline will undergo severe erosion if deprived of its normal Yangtze deltaic sediments which counteract the shore losses to typhoons and nor'easters. Industrial wastes and 250 million gallons/year of raw sewage now dumped in the river and carried to sea would accumulate in the reservoir and turn it into an unsightly, unhealthy, hypoxic, stinking mess. 17.Failure of the Three-Gorges Dam would release a monstrous flood, greater than most pre-dam ones, that would destroy the Gezhou Dam 30 miles downstream via a domino effect; while drowning millions of people on the fertile floodplain and in Shanghai. 18.A dam rupture could occur as a result of warfare, sabotage or earthquake. In 1961, Xinfengjian Dam near Canton was severely damaged by a 6.1-magnitude quake caused by weight stresses of its concrete and reservoir water. Finally, the reservoir would cover the breathtaking vistas that have inspired great Chinese writers and artists for millennia -- the gorges' spectacular cliffs and waterfalls, and the beautiful birds and wildlife living there. 19.Some of the negative effects could be avoided (while retaining many of the positive ones) by building several small check dams on the Yangtze's tributaries instead of one huge dam directly upstream of a small one -- but this scenario, despite its practicality, is as likely to happen as a request to the pharaohs thousands of years ago would have been to build smaller pyramids. 20.Indeed, modern Egypt's giant Aswan Dam on the Nile River has not lived up to its advance expectations (it was built with aid from the Soviets after the US declined to help out). In addition to silt, its upstream reservoir is filling with dead water-hyacinths and other aquatic vegetation that have increased explosively in the warm, calm, nutrient-laden reservoir. 21.The Nile's downstream waters, tamed into slow movement through canals and irrigation ditches in Egypt's rural areas, have begun to ruin the fertile floodplain soils through salt deposits in the fields that previously had been washed out of the farmlands by the annual floods which no longer occur. 22. Expensive fertilizers must now be used to replace the soil nutrients formerly deposited on the fields by the floods, and a debilitating human disease, schistosomiasis, flourishes in rural areas because stagnant-water snail vectors can survive in the canals. And the Nile's discharge to the Mediterranean is so low that saltwater intrusion has affected the groundwater in wells near the coast. 23.Big dams can always be built, but that doesn't mean they will work. Why doesn't China listen to its excellent environmental and geological scientists and chart a better course for its mighty Yangtze River? 24.SHANGHAI—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. 25.Chinese officials staged a sudden about-face, acknowledging for the first time that the massive hydroelectric dam, sandwiched between breathtaking cliffs on the Yangtze River in central China, may be triggering landslides, altering entire ecosystems and causing other serious environmental problems—and, by extension, endangering the millions who live in its shadow. 26.The project management and the Chinese state regard the project as an historic engineering, social and economic success, with the design of state of the art large turbines, and a move toward the reduction of greenhouse gas emissions. 27.However, the dam has also flooded archaeological and cultural sites and displaced some 1.24 million people, and is causing significant ecological changes, including an increased risk of landslides. 28.The building of the dam has been a controversial topic both in China and abroad. 29.The blocking of sediments behind the dam means that these nutrients may not reach fertile farmland downstream of the dam. This could reduce the fertility of the land. 30The destruction of the villages also leads to problems of pollution. The Yangtze River is already polluted from the shipping of coal, acid rain, and its central location in Chinese industrial activity. 31.A number of species will be adversely affected by the construction of the dam. There are 300 species of fish in the Yangtze River. The dam will create a barrier in the river that these species will not be able to cross. Fish will not be able to travel upstream to spawn, so the populations of the species will decrease. 1.However, Rivers International say the Dam has driven fish species to extinction, caused frequent toxic algae blooms and is subjecting the area to erosion and frequent landslides 2.There are smarter ways of generating energy and managing floods than by building outdated mega-projects. 3.Three Gorges Dam across China’s mighty Yangtze River threatens to become an environmental catastrophe. 4.Three Gorges Dam is a disaster because It is causing trouble for the villagers. 5.The water level behind China's massive Three Gorges dam to full capacity this month. 6.We have never stopped talking about the problems but our voice was too weak. 7.The reservoir could also break up land bridges into small islands, animals and plants. 8.Even the Chinese government suspects the massive dam may cause significant environmental damage. 9.To determine the true toll, the Three Gorges Dam is taking on animal and plant species 10. Since the dam is in a earthquake zone it will cause earthqua\e and landslides. 11. Even the government suspect the massive dam may cause significant environmental damage. ||  || [|lauren02px2018] 1.It will kill fish due to the change of water temperature. 2.80% of the cities do not have sewage system and it's cheaper toxins in the Yangtze River. 3. When plans for the dam were first approved in 1992, human rights activists voiced concern about the people who would be forced to relocate to make room for it. 4.Inhabited for several millennia, the Three Gorges region is now a major part of western China's development boom. 5.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. 6.SHANGHAI—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. ||  ||
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