This is an accepted version of this page The Three Gorges Dam (simplified Chinese: 三峡大坝; traditional Chinese: 三峽大壩; pinyin: Sānxiá Dàbà) is a hydroelectric gravity dam that spans the Yangtze River near Sandouping in Yiling District, Yichang, Hubei province, central China, downstream of the Three Gorges.

The world's largest power station by installed capacity (22,500 MW),[5][6] the Three Gorges Dam generates 95±20 TWh of electricity per year on average, depending on the amount of precipitation in the river basin.

As a result, the Chinese government considers the project a source of national pride and a major social and economic success.

In 1944, the United States Bureau of Reclamation's head design engineer, John L. Savage, surveyed the area and drew up a dam proposal for a "Yangtze River Project".

It is not known whether this solution was considered for its water-saving performance or because the engineers thought the difference in height between the river above and below the dam too great for alternative methods.

[36] During China's emphasis on the Four Modernizations during its early period of Reform and Opening Up, The Communist Party revived plans for the dam and proposed to start construction in 1986.

[42][43] Made of concrete and steel, the dam is 2,335 m (2,554 yd; 1.451 mi) long and 185 m (607 ft) above sea level at its top.

[79] On June 30, 2009, after the river flow rate increased to over 24,000 m3/s, all 28 generators were switched on, producing only 16,100 MW because the head available during flood season is insufficient.

The maximum power-output curves were calculated based on the average flow rate at the dam site, assuming the water level is 175 m and the plant gross efficiency is 90.15%.

[82][83] The Three Gorges Dam reached its design-maximum reservoir water level of 175 m (574 ft) for the first time on October 26, 2010, in which the intended annual power-generation capacity of 84.7 TWh was realized.

The DC transmission line HVDC Three Gorges – Guangdong to the South China Grid has a capacity of 3,000 MW.

At current levels, 80% of the land in the area is eroding, depositing about 40 million tons of sediment into the Yangtze annually.

The absence of silt downstream has three effects: Erosion in the reservoir, induced by rising water, causes frequent major landslides that have led to noticeable disturbance in the reservoir surface, including two incidents in May 2009 when somewhere between 20,000 and 50,000 cubic metres (26,000 and 65,000 cu yd) of material plunged into the flooded Wuxia Gorge of the Wu River.

[94] Research by the United Nations Food and Agriculture Organization suggested that the Asia-Pacific region would gain about 6,000 km2 (2,300 sq mi) of forest by 2008.

[104] The proportion of forested area in the region surrounding the Three Gorges Dam dropped from 20% in 1950 to less than 10% as of 2002,[104] adversely affecting all plant species there.

In fact, Chinese Government scholars even claim that the Three Gorges Dam directly caused the extinction of the baiji.

[106] Of the 3,000 to 4,000 remaining critically endangered Siberian crane, many spend the winter in wetlands that the Three Gorges Dam will destroy.

Millions of people live downstream of the dam, with many large, important cities like Wuhan, Nanjing, and Shanghai located adjacent to the river.

The flood waters covered Wuhan, a city of eight million people, for over three months, and the Jingguang Railway was out of service for more than 100 days.

[115] The dam cannot protect against some of the large tributaries downstream, including the Xiang, Zishui, Yuanshui, Lishui, Hanshui, and Gan.

[118] This increases the flow rate of the river downstream, providing fresh water for agricultural and industrial usage, and improving shipping conditions.

Since the filling of the reservoir in 2003, the Three Gorges Dam has supplied an extra 11 km3 (2.6 cu mi) of fresh water to downstream cities and farms over the course of the dry season.

The dam's reservoir rose nearly 3 m (9.8 ft) in 24 hours and reduced the outflow to 40,000 m3/s (1.4 million cu ft/s) in discharges downstream, preventing any significant impact on the middle and lower river.

The 88-kilometre-long (55 mi) northern portage railway (北岸翻坝铁路) will run from the Taipingxi port facility (太平溪港) on the northern side of the Yangtze, just upstream from the dam, via Yichang East Railway Station to the Baiyang Tianjiahe port facility in Baiyang Town (白洋镇), below Yichang.

[144] These people were moved to new homes by the Chinese government, which considered the displacement justified by the flood protection provided for the communities downstream of the dam.

[145] Between 2002 and 2005, Canadian photographer Edward Burtynsky documented the impact of the project on the surrounding areas, including the town of Wanzhou.

[146][147] Other photographers who recorded the change include Chengdu-based Muge,[148] Paris-based Zeng Nian (originally from Jiangsu),[149] and Israeli Nadav Kander.

[157] The United States Department of Defense reported that in Taiwan, "proponents of strikes against the mainland apparently hope that merely presenting credible threats to China's urban population or high-value targets, such as the Three Gorges Dam, will deter Chinese military coercion".

[159] The notion that the military in Taiwan would seek to destroy the dam provoked an angry response from the mainland Chinese media.

[160] Former Taiwanese Ministry of Defense advisor Sung Chao-wen, called the notion of using cruise missiles to destroy the Three Gorges Dam "ridiculous", saying missiles would deliver minimal damage to the reinforced concrete, and any attack attempts would have to go through multiple layers of ground and air defenses.