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Three Gorges Dam

The Three Gorges Dam is the World's Largest Hydroelectric Dam

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Three Gorges Dam

Aerial view of the Three Gorges Dam, Yangtze River, Yichang, Hubei, China. The dam is the world's largest capacity hydroelectric power station.

Stuart Dee/Getty Images
China’s Three Gorges Dam is the world’s largest hydroelectric dam based on generating capacity. It is 1.3 miles wide, over 600 feet in height, and has a reservoir that stretches 405 square miles. The reservoir helps control flooding on the Yangtze River basin and allows 10,000-ton ocean freighters to sail into the interior of China six months out of the year. The dam’s 32 main turbines are capable of generating as much electricity as 18 nuclear power stations and it is built to withstand a magnitude 7.0 earthquake. The dam cost $59 billion and 15 years to construct. It is the largest project in China’s history since the Great Wall.

History of the Three Gorges Dam

The idea for the Three Gorges Dam was first proposed by Dr. Sun Yat-Sen, the pioneer of the Republic of China, in 1919. In his article, entitled “A Plan to Development Industry”, Sun Yat-Sen mentions the possibility of damming the Yangtze River to help control floods and generate electricity.

In 1944, an American dam expert named J.L. Savage was invited to do field research on possible locations for the project. Two years later, the Republic of China signed a contract with the U.S. Bureau of Reclamation to design the dam. More than 50 Chinese technicians were then sent to the United States to study and participate in the creation process. However, the project was shortly abandoned due to the Chinese civil war that followed World War II.

Talks of the Three Gorges Dam resurfaced in 1953 due to continuous floods that occurred on the Yangtze that year, killing over 30,000 people. One year later, the planning phase began once more, this time under the collaboration of Soviet experts. After two years of political debates over the size of the dam, the project was finally approved by the Communist Party. Unfortunately, plans for the construction were once again interrupted, this time by the disastrous political campaigns of the “Great Leap Forward” and the “Proletarian Cultural Revolution."

The market reforms introduced by Deng Xiaoping in 1979 emphasized the necessity to produce more electricity for economic growth. With approval from the new leader, the location of the Three Gorges Dam was then officially determined, to be located at Sandouping, a town in the Yiling District of the Yichang prefecture, in the province of Hubei. Finally, on December 14, 1994, 75-years since inception, the construction of the Three Gorges Dam finally began.

The dam was operational by 2009, but continuous adjustments and additional projects are still ongoing.

Negative Impacts of the Three Gorges Dam

There is no denying of the Three Gorges Dam’s significance to China’s economic ascension, but its construction has created an assortment of new problems for the country.

In order for the dam to exist, over a hundred towns had to be submerged, resulting in the relocation of 1.3 million people. The resettlement process has damaged much of the land as rapid deforestation lead to soil erosion. Furthermore, many of the new designated areas are uphill, where the soil is thin and agricultural productivity is low. This has become a major problem since many of those forced to migrate were poor farmers, who rely heavily on crop outputs. Protests and landslides have become very common in the region.

The Three Gorges Dam area is rich in archaeological and cultural heritage. Many different cultures have inhabited the areas that are now underwater, including the Daxi (circa 5000-3200 B.C.E), which are earliest Neolithic culture in the region, and its successors, the Chujialing (circa. 3200-2300 B.C.E), the Shijiahe (circa 2300-1800 B.C.E) and the Ba (circa 2000-200 B.C.E). Due to the damming, it is now virtually impossible to collect and document these archaeological sites. In 2000, it was estimated that the area inundated contained at least 1,300 cultural heritage places. It is no longer possible for scholars to recreate the settings where historical battles took place or where cities were built. The construction also changed the landscape, making it impossible now for people to witness the scenery which inspired so many ancient painters and poets.

The creation of the Three Gorges Dam has lead to the endangerment and extinction of many plant and animals. The Three Gorges region is considered a biodiversity hotspot. It is home to over 6,400 plant species, 3,400 insect species, 300 fish species, and more than 500 terrestrial vertebrate species. The disruption of the river’s natural flow dynamics due to blockage will affect the migratory paths of fish. Due to the increase of ocean vessels in the river channel, physical injuries such as collisions and noise disturbances have greatly accelerated the demise of local aquatic animals. The Chinese river dolphin which is native to the Yangtze River, and the Yangtze finless porpoise have now become two of the most endangered cetaceans in the world.

The hydrological alternations also affect fauna and flora downstream. Sediment build-up in the reservoir has altered or destroyed floodplains, river deltas, ocean estuaries, beaches, and wetlands, which provide habitation for spawning animals. Other industrial processes, such as the release of toxic substances into the water also compromise the biodiversity of the region. Because the water flow is slowed due to the reservoir impoundment, the pollution will not be diluted and flushed to the sea in the same manner as before the damming. Additionally, by filling the reservoir, thousands of factories, mines, hospitals, garbage dumping sites and graveyards have been flooded. These facilities can subsequently release certain toxins such as arsenic, sulfides, cyanides, and mercury into the water system.

Despite helping China reduce its carbon emissions immensely, the social and ecological consequences of the Three Gorges Dam have made it very unpopular to the international community.

References

Ponseti, Marta & Lopez-Pujol, Jordi. The Three Gorges Dam Project in China: History and Consequences. Revista HMiC , University of Autonoma de Barcelona: 2006

Kennedy, Bruce (2001). China’s Three Gorges Dam. Retrieved from http://www.cnn.com/SPECIALS/1999/china.50/asian.superpower/three.gorges/

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