Why Built the Three Gorges Dam ?
- Flooding One of the main reasons that the Three Gorges dam was built was to prevent flooding further downstream. ...
- Power Generation Another reason why the Three Gorges Dam was constructed was to generate electricity. ...
- Environmental Impact The dam has been designed to impact the environment as little as possible. ...
- Visiting the Dam ...
What are the negative effects of the Three Gorges Dam?
What are the negative impacts of the Three Gorges Dam? Chinese and foreign scientists, meanwhile, warned that the dam could endanger the area’s remaining residents. Among their concerns: landslides caused by increased pressure on the surrounding land, a rise in waterborne disease, and a decline in biodiversity.
How much water does Three Gorges Dam control?
Three Gorges Dam can intercept small floods and reduce big floods by storing water in reservoir with a water capacity of 22.15 billion cubic meters (28.9 billion cubic yards).
What effect does the Three Gorges Dam have on people?
What effect does the Three Gorges Dam have on people? With the construction of the Three Gorges Dam, that flood interval is increased to one-hundred years. This means that many more lives will be saved, since in the past, the frequency of the Yangtze River flooding has claimed thousands of lives. The presence of the dam indicates less flooding ...
What towns flooded by Three Gorges Dam?
Text by Aaron Rothman. On November 4, 2008, water rose over Kaixian, China, ending its history of nearly 2000 years. Located on the Yangtze River, 180 miles upstream from the Three Gorges Dam — the largest water control project ever built — Kaixian was the final town submerged by the dam’s reservoir.
What is the purpose of the 3 Gorges dam?
HydropowerFlood controlTourismThree Gorges Dam/Purposes
What are 3 benefits of the Three Gorge dam?
On one hand, the benefits of the Three Gorges Dam are flood control, power generation, navigation, aquaculture, tourism, ecological protection, environmental purification, development-oriented resettlement, transfer of water from southern China to northern China, and water supply and irrigation.
What are 3 positive effects of the dam being built?
Dams, which contribute to the national economy from many aspects like irriga- tion, drinking water supply, flood control, electricity generation, fishing, tourism, are also effective in increasing the living and cultur level of the region that they were constructed.
Is the Three Gorges Dam good for the environment?
That biodiversity is threatened as the dam floods some habitats, reduces water flow to others, and alters weather patterns. Economic development has spurred deforestation and pollution in surrounding provinces in central China, endangering at least 57 plant species, including the Chinese dove tree and the dawn redwood.
How much power is in the Three Gorges Dam?
101.6 TWh (366 PJ) (2018) The Three Gorges Dam is a hydroelectric gravity dam that spans the Yangtze River by the town of Sandouping, in Yiling District, Yichang, Hubei province, central China, downstream of the Three Gorges. The Three Gorges Dam has been the world's largest power station in terms of installed capacity (22,500 MW) since 2012.
What is the Three Gorges Dam?
The Three Gorges Dam is a steel-concrete gravity dam.
How much did the Three Gorges Dam cost?
The government estimated that the Three Gorges Dam project would cost 180 billion yuan ( US$22.5 billion). By the end of 2008, spending had reached 148.365 billion yuan, among which 64.613 billion yuan was spent on construction, 68.557 billion yuan on relocating affected residents, and 15.195 billion yuan on financing.
What species of fish are endangered by the Three Gorges Dam?
Other aquatic species have been endangered by the dam, particularly the baiji, or Chinese river dolphin, now extinct. In fact, Chinese Government scholars even claim that the Three Gorges Dam directly caused the extinction of the baiji.
What are the hazards of the Yangtze dam?
At current levels, 80% of the land in the area is experiencing erosion, depositing about 40 million tons of sediment into the Yangtze annually. Because the flow is slower above the dam, much of this sediment will now settle there instead of flowing downstream, and there will be less sediment downstream.
How much power does a three gorge generator produce?
The main generators weigh about 6,000 tonnes each and are designed to produce more than 700 MW of power. The designed hydraulic head of the generator is 80.6 metres (264 ft). The flow rate varies between 600–950 cubic metres per second (21,000–34,000 cu ft/s) depending on the head available. The greater the head, the less water needed to reach full power. Three Gorges uses Francis turbines. The turbine diameter is 9.7/10.4 m (VGS design/Alstom's design) and the rotation speed is 75 revolutions per minute. This means that in order to generate power at 50 Hz, the generator rotors have 80 poles. Rated power is 778 MVA, with a maximum of 840 MVA and a power factor of 0.9. The generator produces electrical power at 20 kV. The electricity generated is then stepped-up to 500 kV for transmission at 50 Hz. The outer diameter of the generator stator is 21.4/20.9 m. The inner diameter is 18.5/18.8 m. The stator, the biggest of its kind, is 3.1/3 m in height. Bearing load is 5050/5500 tonnes. Average efficiency is over 94%, and reaches 96.5%.
Why are Chinese paddlefish extinct?
The Chinese paddlefish is also believed extinct in part due to the dam blocking its migration. Of the 3,000 to 4,000 remaining critically endangered Siberian crane, a large number currently spend the winter in wetlands that will be destroyed by the Three Gorges Dam.
Overview
The Three Gorges Dam is a hydroelectric gravity dam that spans the Yangtze River by the town of Sandouping, in Yiling District, Yichang, Hubei province, central China, downstream of the Three Gorges. The Three Gorges Dam has been the world's largest power station in terms of installed capacity (22,500 MW) since 2012. The dam generates an average 95±20 TWh of electricity per year, depending on an…
History
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. In 1932, the Nationalist government, led by Chiang Kai-shek, began preliminary work on plans in the Three Gorges. In 1939, during the Second Sin…
Composition and dimensions
Made of concrete and steel, the dam is 2,335 m (7,661 ft) long and the top of the dam is 185 m (607 ft) above sea level. The project used 27.2 million m (35.6 million cu yd) of concrete (mainly for the dam wall), used 463,000 tonnes of steel (enough to build 63 Eiffel Towers), and moved about 102.6 million m (134.2 million cu yd) of earth. The concrete dam wall is 181 m (594 ft) high above th…
Economics
The government estimated that the Three Gorges Dam project would cost 180 billion yuan (US$22.5 billion). By the end of 2008, spending had reached 148.365 billion yuan, among which 64.613 billion yuan was spent on construction, 68.557 billion yuan on relocating affected residents, and 15.195 billion yuan on financing. It was estimated in 2009 that the construction cost would be recove…
Power generation and distribution
Power generation is managed by China Yangtze Power, a listed subsidiary of China Three Gorges Corporation (CTGC) – a Central Enterprise SOE administered by SASAC. The Three Gorges Dam is the world's largest capacity hydroelectric power station with 34 generators: 32 main generators, each with a capacity of 700 MW, and two plant power generators, each with capacity of 50 MW, makin…
Environmental impact
According to the National Development and Reform Commission, 366 grams of coal would produce 1 kWh of electricity during 2006. From 2003 to 2007, power production equaled that of 84 million tonnes of standard coal.
Two hazards are uniquely identified with the dam. One is that sedimentation projections are not agreed upon, and the other is that the dam sits on a seismi…
Floods, agriculture, industry
An important function of the dam is to control flooding, which is a major problem for the seasonal river of the Yangtze. Millions of people live downstream of the dam, with many large, important cities like Wuhan, Nanjing, and Shanghai located adjacent to the river. Plenty of farm land and China's most important industrial area are built beside the river.
Navigating the dam
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.
There are two series of ship locks installed near the dam (30°50′12″N 111°1′1…