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77-642: Sanxia may refer to: Three Gorges , on the Yangtze River in the People's Republic of China Three Gorges Dam Sanxia Prison , in Chongqing, People's Republic of China Sanxia District , New Taipei, Taiwan See also [ edit ] Tam Hiệp (disambiguation) [REDACTED] Topics referred to by the same term This disambiguation page lists articles about distinct geographical locations with

154-634: A capacity of 700 MW, and two plant power generators, each with capacity of 50 MW, for a total of 22,500 MW. Among the 32 main generators, 14 are installed on the dam's north side, 12 on the south side, and the remaining six in the underground power plant in the mountain south of the dam. Annual electricity generation in 2018 was 101.6 TWh, which is 20 times more than the Hoover Dam . The main generators each weigh approximately 6,000 tonnes and are designed to produce more than 700 MW of power each. The designed hydraulic head of

231-448: A dam proposal for a "Yangtze River Project". Some 54 Chinese engineers went to the US for training. The original plans called for the dam to employ a unique method for moving ships: the ships would enter locks at the dam's lower and upper ends and then cranes would move them from each lock to the next. Groups of craft would be lifted together for efficiency. It is not known whether this solution

308-495: A flat rate of ¥250 per MWh (US$ 35.7) until July 2, 2008. Since then, the price has varied by province, from ¥228.7 to ¥401.8 per MWh. Higher-paying customers, such as Shanghai , receive priority. Nine provinces and two cities consume power from the dam. Power distribution and transmission infrastructure cost about 34.387 billion yuan. Construction was completed in December 2007, one year ahead of schedule. Power

385-427: A flood in the same area caused billions of dollars worth of damage, when 2,039 km (787 sq mi) of farmland were flooded. The flood affected more than 2.3 million people, killing 1,526. In early August 2009, the largest flood in five years passed through the dam site. During this flood, the dam limited the water flow to less than 40,000 m /s (1.4 million cu ft/s) per second, raising

462-431: A kind of elevator for vessels. The ship lift can lift ships of up to 3,000 tons. The vertical distance traveled is 113 m (371 ft), and the size of the ship lift's basin is 120 m × 18 m × 3.5 m (394 ft × 59 ft × 11 ft). The ship lift takes 30 to 40 minutes to transit, as opposed to the three to four hours for stepping through the locks. One complicating factor

539-494: A move toward limiting greenhouse gas emissions . However, the dam has led to some ecological changes, including an increased risk of landslides, which have made it controversial domestically and abroad. Sun Yat-sen envisioned a large dam across the Yangtze River in The International Development of China (1919). He wrote that a dam capable of generating 30 million horsepower (22 GW)

616-426: A scene, nor had I any similar experience. So I am cheerful to see such a wonder, I feel mountains and waters all had spirits, and I am thrilled to encounter this bosom friend after seeking so long. In his poem Setting out from Baidicheng , Li Bai ( 李白 ) depicts this place, saying, While monkeys keep howling at both sides of the river, the boat has swiftly passed thousands of mountains. Between winter and spring,

693-549: A ship lift completed in 2015. Both the dam and the Three Gorges Reservoir has had a massive impact on the region's ecology and people, involving the mass relocation of towns and villages. The higher water level has changed the scenery of the Three Gorges so that the river is wider and the mountains appear lower. However, the mountains still tower above the river, and the gorges continue to offer views of

770-477: A total of 198 million tonnes of freight passed through the locks. The freight capacity of the river increased six times and the cost of shipping was reduced by 25%. Originally, the total capacity of the ship locks was expected to reach 100 million tonnes per year. In 2022, their cargo turnover reached 159.65 million tons, with an annual increase of 6% over the past few years. These locks are staircase locks , whereby inner lock gate pairs serve as both

847-470: Is 181 m (594 ft) high above the rock basis. When the water level is at its maximum of 175 m (574 ft) above sea level, 110 m (361 ft) higher than the river level downstream, the dam reservoir is on average about 660 km (410 mi) in length and 1.12 km (3,675 ft) in width. It contains 39.3 km (31,900,000  acre⋅ft ) of water and has a total surface area of 1,045 km (403 sq mi). On completion,

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924-657: 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 in terms of installed capacity (22,500  MW ), the Three Gorges Dam generates 95±20  TWh of electricity per year on average, depending on the amount of precipitation in

1001-568: Is approximately 200 km (120 mi) in length, while the Three Gorges themselves occupy about 120 km (75 mi) within this region: this has attracted global attention to the Three Gorges Dam and changed the culture and environment of the region. Although it is primarily famous for its scenery, the Three Gorges region is historically and culturally important in China. Many settlements and archaeological sites were submerged by

1078-544: Is distributed over multiple 500 kV transmission lines. Three direct current (DC) lines to the East China Grid carry 7,200 MW: Three Gorges – Shanghai (3,000 MW), HVDC Three Gorges – Changzhou (3,000 MW), and HVDC Gezhouba – Shanghai (1,200 MW). The alternating current (AC) lines to the Central China Grid have a total capacity of 12,000 MW. The DC transmission line HVDC Three Gorges – Guangdong to

1155-448: Is enough flow, power output is limited by plant generating capacity. 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%. The actual power output in 2008 was obtained based on the monthly electricity sent to the grid. The Three Gorges Dam reached its design-maximum reservoir water level of 175 m (574 ft) for

1232-537: Is home to 6,388 plant species, which belong to 238 families and 1,508 genera. Of these species, 57 are endangered. These rare species are also used as ingredients in traditional Chinese medicines. 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, adversely affecting all plant species there. The region also provides habitats to hundreds of freshwater and terrestrial animal species. Freshwater fish are especially affected by dams due to changes in

1309-511: Is made up of five stages, with transit time at around four hours. Maximum vessel size is 10,000 tons. The locks are 280 m long, 35 m wide, and 5 m deep (918 × 114 × 16.4 ft). That is 30 m (98 ft) longer than those on the St Lawrence Seaway , but half as deep. Before the dam was constructed, the maximum freight capacity at the Three Gorges site was 18.0 million tonnes per year. From 2004 to 2007,

1386-748: The Great Leap Forward and the Cultural Revolution slowed progress. After the 1954 Yangtze River Floods , in 1956, Mao wrote " Swimming ", a poem about his fascination with a dam on the Yangtze River. In 1958, after the Hundred Flowers Campaign , some engineers who spoke out against the project were imprisoned. During China's emphasis on the Four Modernizations during its early period of Reform and Opening Up , The Communist Party revived plans for

1463-554: The Jingguang Railway was out of service for more than 100 days. The 1954 flood carried 50 cubic kilometres (12 cu mi) of water. The dam could only divert the water above Chenglingji, leaving 30 to 40 km (7.2 to 9.6 cu mi) to be diverted. The dam cannot protect against some of the large tributaries downstream, including the Xiang , Zishui , Yuanshui , Lishui , Hanshui , and Gan . In 1998,

1540-473: The Ministry of Environmental Protection , as of April 2007, more than 50 new plants could treat 1.84 million tonnes per day, 65% of the total need. About 32 landfills were added, which could handle 7,664.5 tonnes of solid waste every day. Over one billion tons of wastewater are released annually into the river, which was more likely to be swept away before the reservoir was created. This has left

1617-478: 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: that sedimentation projections are not agreed upon, and that the dam sits on a seismic fault . At current levels, 80% of the land in

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1694-689: The Qutang , followed by the Wu , and finally the Xiling gorges—span 193 miles (311 km), beginning at Baidi City of Chongqing , in the west and ending at Nanjing Pass, at Yichang City , Hubei Province , in the east, between which are the Fengjie and Wu Mountains of Chongqing, as well as Badong, Zigui, and Yichang of Hubei Province. After arriving at Yibin ( 宜宾 ), in Sichuan Province ( 四川 ),

1771-476: The Yangtze River ( 长江 ) flows from Jiangjin ( 江津 ), of Chongqing Municipality ( 重庆 ), to Yichang ( 宜昌 ), of Hubei Province ( 湖北 ); and this section of the river is called Chuanjiang ( 川江 ), or "the river of Sichuan". In the past, it was the only waterway that connected Sichuan and Guizhou to China's eastern area. (The Wu River ( 乌江 ) flows past Guizhou and empties into the Yangtze River at Fuling ( 涪陵 ), of Chongqing Municipality). Downstream,

1848-543: The 1990s. This is largely due to China's large reforestation effort . This accelerated after the 1998 Yangtze River floods convinced the government that it should restore tree cover, especially in the Yangtze's basin upstream of the Three Gorges Dam. Concerns about the dam's impact on wildlife predate the National People's Congress's approval in 1992. This region has long been known for its rich biodiversity. It

1925-475: The 2633 members ( 67.11%) voting to support the dam. The Three Gorges Dam was constructed at Sandouping ( 三斗坪 ), Yichang ( 宜昌 ) in Hubei Province ( 湖北 ), in the middle of Xiling Gorge . On May 20, 2006, the reservoir dam was completed, and the water level quickly reached the initial level of 110 meters (360 ft) above the downstream river. The project was completed by the end of 2008, with

2002-913: The Chuanjiang passes the Wu Mountains—the second ladder of the Chinese mainland—which form the Qutang Gorge ( 瞿塘峡 ), the Wu Gorge ( 巫峡 ), and the Xiling Gorge ( 西陵峡 ) along the Yangtze River, which is where this area gets its name. The Three Gorges span from the western, upriver, city of Fengjie , in Chongqing Municipality , to the east, downstream, city of Yichang , in Hubei province . The Three Gorges Reservoir Region

2079-466: The South China Grid has a capacity of 3,000 MW. The dam was expected to provide 10% of China's power. However, electricity demand has increased more quickly than previously projected. Even fully operational and despite its size, on average, it supported only about 1.7% of electricity demand in China in the year of 2011, when the Chinese electricity demand reached 4,692.8 TWh. According to

2156-625: The Three Gorges Dam Construction Fund, profits from the Gezhouba Dam , loans from the China Development Bank , loans from domestic and foreign commercial banks, corporate bonds , and revenue from both before and after the dam had become fully operational. Additional charges were assessed as follows: every province receiving power from the Three Gorges Dam had to pay an extra ¥7.00 per MWh, and

2233-560: The Three Gorges Dam directly caused the extinction of the baiji. 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. Populations of the Yangtze sturgeon are guaranteed to be "negatively affected" by the dam. In 2022 the Chinese paddlefish was declared extinct, with the last confirmed sighting in 2003. In 2005, NASA scientists calculated that

2310-425: The Three Gorges stretching more than 200 miles. The overlapping rocks make up layers of barriers that shield against sky and sunshine so that the sun can only be seen at noon and the moon will merely show at midnight. In summers, water rises to lofty mountains, making all boats floating along or against the river get blocked. Suppose an empire has an urgent decree to issue from Baidi, it will reach Jiangling at sunset of

2387-602: The Three Gorges, but it was not until 1994 that the Three Gorges project officially started. In 1944, the Nationalist government recruited John L. Savage , the Chief Engineer of the United States Bureau of Reclamation, who came to China and made a 10-day investigation of the Three Gorges. Afterwards, he wrote an enthusiastic report on the prospects of a dam. Construction was started on the first of

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2464-674: The Wu Gorge, one of the twelve peaks is known as Fairy Peak. According to folk tradition, it symbolizes a fairy who assisted Yu the Great in controlling the waters and guiding boatmen. The Xiling Gorge comprises a series of famous gorges, including Military Book and Sword Gorge, Yellow Cow Gorge, and Lantern's Shadow Gorge. In 1919, after Sun Yat-sen had put forward the concept in the Plan for Industrial Development of his Founding Strategy  [ zh ] ( 建国方略 ), experts investigated damming

2541-433: The area is eroding, depositing about 40 million tons of sediment into the Yangtze annually. Because the flow is slower above the dam, much of this sediment settles there instead of flowing downstream, and there is less sediment downstream. 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

2618-570: The course of the dry season. During the South China floods in July 2010 , inflows at the Three Gorges Dam reached a peak of 70,000 m /s (2.5 million cu ft/s), exceeding the peak inflow during the 1998 Yangtze River floods . The dam's reservoir rose nearly 3 m (9.8 ft) in 24 hours and reduced the outflow to 40,000 m /s (1.4 million cu ft/s) in discharges downstream, preventing any significant impact on

2695-466: The dam and proposed to start construction in 1986. It emphasized the need to develop hydroelectric power. The Chinese People's Political Consultative Conference became a center of opposition to the proposed dam. It convened panels of experts who recommended delaying the project. The National People's Congress approved the dam in 1992: of 2,633 delegates, 1,767 voted in favour, 177 voted against, 664 abstained, and 25 members did not vote, giving

2772-422: The dam generated an average of 97.22 TWh of electricity per year, higher than Itaipu dam's average of 89.22 TWh of electricity per year during the same period. Due to the extensive 2020 monsoon season rainfall, the annual production reached ~112 TWh that year, which broke the previous world record of annual production by Itaipu Dam equal to ~103 TWh. The State Grid Corporation and China Southern Power Grid paid

2849-484: 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. Large areas of farmland and China's most important industrial area are situated beside the river. The reservoir's flood storage capacity is 22 km (5.3  cu mi ; 18 million  acre⋅ft ). This capacity will reduce

2926-498: The dam was built and used to store water, a large number of cultural relics, including hanging coffins and stone inscriptions that cannot be protected, were covered by the reservoir. 31°01′04″N 110°13′43″E  /  31.01778°N 110.22861°E  / 31.01778; 110.22861 Three Gorges Dam 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 )

3003-496: The dam was designed to increase the Yangtze River's shipping capacity. By providing flood storage space, the dam reduces the potential for flooding downstream, which historically plagued the Yangtze Plain . In 1931, floods on the river caused the deaths of up to 4 million people. As a result, China regards the project as a monumental social and economical success, with the design of state-of-the-art large turbines and

3080-720: The dams at Upper Tsing Yuan Tung, but was halted on August 15, 1947, because of the Chinese Civil War . In February 1958, as the expanded meeting of the Political Bureau of the CPC Central Committee was held at Nanning ( 南宁 ), the Three Gorges Project ( 三峡工程 ) was discussed for the first time, and fierce disputes broke out. In the end, this project was delayed. Over the following three decades, people continued to discuss it. In

3157-572: The day. The distance between them is about 373 miles, and neither a galloping horse nor a flight can run faster than a boat. Yuan Shansong ( 袁山松 ) of the Eastern Jin dynasty wrote a Record of Yichuan's Landscape , which depicts the Three Gorges' grandeur. He wrote, People were always warned literally or orally of the Gorges' swift currents, saying they are horrific, and no one praised the local landscape [as] beautiful. It's [not] till I came to

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3234-512: The designed maximum level of 175 m (574 ft) by 2010. 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. 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

3311-471: The early 1980s, people mentioned it once again, but after repeated discussions and investigations, it was again postponed. On March 6, 1992, a feasibility report was presented at the 5th Session of the 7th National People's Congress (NPC) for discussion and resolution. On April 3 of that year, the NPC voted on a resolution for the dam, and it was passed with an unusually low approval rate for the NPC with only 1767 of

3388-445: The first time on October 26, 2010, in which the intended annual power-generation capacity of 84.7 TWh was realized. It has a combined generating capacity of 22.5 gigawatts and a designed annual generation capacity of 88.2 TWh. In 2012, the dam's 32 generating units generated a record 98.1 TWh of electricity, which accounts for 14% of China's total hydro generation. Between 2012 (first year with all 32 generating units operating) and 2021,

3465-420: The frequency of major downstream flooding from once every 10 years to once every 100 years. The dam is expected to minimize the effect of even a "super" flood. The river flooded in 1954 over an area of 193,000 km (74,500 sq mi), killing 33,169 people and forcing almost 18.9 million people to move. The flood waters covered Wuhan, a city of eight million people, for over three months, and

3542-402: 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 generator's stator , the biggest of its kind, is 3.1/3 m in height; the outer diameter of the stator is 21.4/20.9 m,

3619-454: The generators 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 with a diameter of 9.7/10.4 m (VGS design/Alstom's design) and a rotation speed of 75 revolutions per minute. This means that in order to generate power at 50  Hz ,

3696-477: The inner diameter is 18.5/18.8 m, and the bearing load is 5,050/5,500 tonnes. Average efficiency is over 94%, with a maximum efficiency of 96.5% reached. The generators were manufactured by two joint ventures: Alstom , ABB , Kvaerner , and the Chinese company Harbin Motor; and Voith , General Electric , Siemens (abbreviated as VGS), and the Chinese company Oriental Motor. The technology transfer agreement

3773-472: The last main generator (No. 27) finished its final test on May 23, 2012, the six underground main generators were all operational, raising the capacity to 22.5 GW. After nine years of construction, installation and testing, the power plant was fully operational by July 2012. By August 16, 2011, the plant had generated 500 TWh of electricity. In July 2008 it generated 10.3 TWh of electricity, its first month over 10 TWh. On June 30, 2009, after

3850-435: The legislation an unusually low 67.75% approval rate. Construction started on December 14, 1994. The dam was expected to be fully operational in 2009, but additional projects, such as the underground power plant with six additional generators, delayed full operation until 2012. The ship lift was completed in 2015. The dam raised the water level in the reservoir to 172.5 m (566 ft) above sea level by 2008 and to

3927-405: The main water turbines has a capacity of 700 MW. Combining the capacity of the dam's 32 main turbines with the two smaller generators (50 MW each) that provide power to the plant itself, the total electric generating capacity of the Three Gorges Dam is 22,500 MW. The last major component of the project, the ship lift, was completed in 2015. In addition to generating electricity,

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4004-503: The middle and lower river. 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′10″E  /  30.83667°N 111.01944°E  / 30.83667; 111.01944 ). Each of them

4081-509: The other provinces had to pay an additional charge of ¥4.00 per MWh. No surcharge was imposed on the Tibet Autonomous Region . Power generation is managed by China Yangtze Power , a listed subsidiary of China Three Gorges Corporation (CTGC), a Central Enterprise administered by SASAC . The Three Gorges Dam is the world's largest capacity hydroelectric power station, with 34 generators: 32 main generators, each with

4158-588: The past, the river flowed to the east through the region. As the crust of the locality continued to rise, the river's erosion intensified, and the Three Gorges were carved. The natural beauty of the Three Gorges along the Yangtze River has been appreciated for hundreds of years. In the Northern Wei ( 北魏 ) dynasty, Li Daoyuan ( 酈道元 ) described them in his work, Commentary on the Water Classic ( 水經注 ). There are seamless mountains on both sides of

4235-585: The reservoir flooded a total area of 632 km (156,000 acres) of land, compared to the 1,350 km (330,000 acres) of reservoir created by the Itaipu Dam . The Chinese 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, of 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

4312-511: 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 . In the first four months of 2010, there were 97 significant landslides. The dam catalyzed improved upstream wastewater treatment around Chongqing and its suburban areas. According to

4389-427: The river along vertical fractures, forming precipitous cliffs. When the river flows through areas of softer sandstone and shale , which have less resistance to erosion, the erosive effect is increased, carving wide valleys. There are different theories on how the Three Gorges were formed, but geographers and geologists have generally reached a consensus, believing mountain folding in the east of Sichuan Province and

4466-401: The river basin. After the extensive monsoon rainfalls of 2020, the dam's annual production reached nearly 112 TWh, breaking the previous world record of ~103 TWh set by Itaipu Dam in 2016. The dam's body was completed in 2006; the power plant was completed and fully operational by 2012, when the last of the main water turbines in the underground plant began production. Each of

4543-458: The river downstream, providing fresh water for agricultural and industrial usage, and improving shipping conditions. The water level upstream drops from 175 to 145 m (574 to 476 ft), in preparation for the rainy season. The water also powers the Gezhouba Dam downstream. Since the filling of the reservoir in 2003, the Three Gorges Dam has supplied an extra 11 km (2.6 cu mi) of fresh water to downstream cities and farms over

4620-475: The river flow rate increased to over 24,000 m /s, all 28 generators were switched on, producing only 16,100 MW because the head available during flood season is insufficient. During an August 2009 flood, the plant first reached its maximum output for a short period. During the November to May dry season, power output is limited by the river's flow rate, as seen in the diagrams on the right. When there

4697-477: The same name. If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Sanxia&oldid=1212907064 " Category : Place name disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Three Gorges The Three Gorges—comprising

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4774-470: The shadows of rocks and woods are reflected in the green pool accompanied by white, swift currents. Cascades plunge and flow across cypresses increasing at extremely high peaks. Clean water, flourishing trees, lofty mountains and luxuriant grasses compose the landscape. When the sun starts to rise or frost falls in the morning, forests and streams are chilly and solemn, and one can often hear monkeys howling from peaks. Their cries sound sad and strange and last in

4851-535: The shift of water mass stored by the dams would increase the total length of the Earth 's day by 0.06 microseconds and make the Earth slightly more round in the middle and flat on the poles . A study published in 2022 in the journal Open Geosciences suggests that the change of reservoir water level affects the gravity field in western Sichuan, which in turn affects the seismicity in that area. An important function of

4928-483: The site that I felt quite gleeful and started to understand seeing is believing. The overlapping cliffs, the elegant peaks and the grotesque structures, they all constitute the scenery far from expression. The lush, solemn woods stood erected in the cloudy air. I can raise up my head to appreciate what's above, and look down to see reflections, and the more acquainted I get with this place, the better I feel. I spent two nights there, forgetting to return. I had never seen such

5005-493: The surrounding cliffs. The riverboat companies operating on the Three Gorges are experiencing an increase in demand for river cruises. The increased width and depth of the river permits larger ships through the gorges, and there has been a significant increase in river traffic of all kinds, including bulk cargo and container barges. After the construction of the Three Gorges Dam was approved, archaeologists were allowed time and resources to carry out rescue work. However, after

5082-399: The upper gate of the chamber below and the lower gate of the chamber above. The gates are the vulnerable hinged type, which, if damaged, could temporarily render the entire flight unusable. As there are separate sets of locks for upstream and downstream traffic, this system is more water efficient than bi-directional staircase locks. In addition to the canal locks, there is a ship lift ,

5159-443: The upstream reservoir of the Three Gorges Dam . Due to the lithological conditions of its different regions, the valleys of the Three Gorges are narrow in some areas and broad in others. Most narrow valleys occur in regions where there is limestone , which is relatively hard and resists erosion. However, water can flow along deep vertical fractures, eroding underneath. As the limestone bed is gradually undercut, parts of it fall into

5236-415: The upstream water level from 145.13 m (476.1 ft) on August 1, to 152.88 m (501.6 ft) on August 8. A full 4.27 km (1.02 cu mi) of flood water was captured and the river flow was cut by as much as 15,000 m (530,000 cu ft) per second. The dam discharges its reservoir during the dry season every year, between December and March. This increases the flow rate of

5313-548: The valleys for quite a while, because of that, local fishers think the Wu Gorge is the longest of the Three Gorges in the east of Sichuan province. The Three Gorges have renowned scenic spots, such as the Kuimen ( 夔門 ), located at the western entrance to the Three Gorges. The cliffs on both sides appear to some as having been cut by knives or axes. Among the Wu Mountains that are located at the northern and southern beaches of

5390-549: The water stagnant, polluted and murky. In 1997, the Three Gorges area had 10% forestation, down from 20% in the 1950s. Research by the United Nations Food and Agriculture Organization suggested that the Asia-Pacific region would gain about 6,000 km (2,300 sq mi) of forest by 2008. That is a significant change from the 13,000 km (5,000 sq mi) net loss of forest each year in

5467-483: The water temperature and flow regime. Many other fish are injured in the hydroelectric plants' turbine blades. This is particularly detrimental to the region's ecosystem because the Yangtze River basin is home to 361 different fish species and accounts for 27% of China's endangered freshwater fish species. 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

5544-486: The west of Hubei Province, including the Wu Mountains ( 巫山 ), were the outcome of the Yanshanian movement ( 燕山運動 ) around 70 million years ago. The gorges run from southwest to northeast, then turn, and from west to east, with terrain lowering gradually from south to north. The western and eastern parts of the area, between the southern mountains and Bashan Mountain ( 巴山 ), in the north, are comparatively lower; and in

5621-584: 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. No construction work was performed because of the Nationalists' worsening situation in the Chinese Civil War. After the 1949 Communist Revolution , Mao Zedong supported the project, but began the Gezhouba Dam project nearby first, and economic problems including

5698-407: Was estimated in 2009 that the cost of construction would be fully recouped when the dam had generated 1,000 terawatt-hours (3,600 PJ) of electricity, yielding 250 billion yuan; total cost recovery was thus expected to be completed ten years after the dam became fully operational. In fact, the entire cost of the Three Gorges Dam was recovered by December 20, 2013. Funding sources include

5775-438: Was eventually achieved on October 18, 2006, after the water level reached 156 meters. On the south side, main generator No. 22 started up on June 11, 2007, and No. 15 became operational on October 30, 2008. The sixth (No. 17) began operation on December 18, 2007, raising capacity to 14.1 GW, exceeding that of Itaipu dam (14.0 GW) to become the world's largest hydro power plant by capacity. When

5852-552: 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 Sino-Japanese War , Japanese military forces occupied Yichang and surveyed the area. In 1944, the United States Bureau of Reclamation 's head design engineer, John L. Savage , surveyed the area and drew up

5929-412: Was signed together with the contract. Most of the generators are water-cooled. Some of the newer ones are air-cooled, making them simpler in design and easier to manufacture and maintain. The first north-side main generator (No. 2) started up on July 10, 2003. The north side became completely operational on September 7, 2005, with the implementation of generator No. 9. Full power (9,800 MW)

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