The Three Gorges Dam

Factfile

DIMENSIONS: 181m high and 2.3km wide

AREA FLOODED: 632km(squared)

COST: £25.5 billion

BUILT: started 1994, finished 2009 

INCREASED DEPTH: 110 m (reduced to 80m when flood risk downstream)

RESERVOIR: Holds back 20 billion tons of water

ENERGY: 85 billion kilowatt hours a year by 2009

LOCATION: Yichang on the river Yangste. 

Positive impacts of the Three Gorges Dam:

Social

Tourist attraction - Provides income from visitors but also social and recreational benefits from those visiting the dam and reservoirs. 

Environmental

Cleaner and sustainable energy resource - This amount of reliable renewable power production capacity can keep China from generating electricity from fossil fuels which can harm the environment and eventually will run out. The dam is a stable source of great power that will continue after fossil fuels have run out.

Flood Control - The dam helps to manage and control the flow of the water and prevent flooding which has caused significant damage in the past. 

Economical 

Energy production - China is a huge country with the world's largest population. This dam can produce a massive amount of energy amounting to 18.2 GW of electric power, equivalent to 18 nuclear power stations. This is needed to supply sufficient energy to support their busy economy, flourishing industry and their ever growing and developing society. 

Income generator - The dam also generates very significant income for both the local community and for the nation as a whole. The project also produced many thousands of jobs during the construction process and now to maintain the dam and power plant. 

Better navigation - The river has been widened as a result of the project which makes it more navigable than ever. Ships and larger boats can now pass through to the delta providing a better and more efficient transport network for goods and people. 

The negative impacts of the Three Gorges Dam

Social

Relocation of locals - Approximately 1.3 million local people have been relocated or displaced (often forcibly without compensation) and more than a hundred towns have been submerged to enable the construction of this dam.

Perished important archeological and cultural sites - The construction of this dam destroyed approximately thousands of archaeological sites forever

Environmental

Negative environmental impact - The dam is likely to have a detrimental impact on the environment by pollution and erosion threatening the lives of countless species. Sediment build-up in the reservoir has altered or destroyed floodplains 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. The disruption of the rivers 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. 

Geographical impact - Following construction of the dam the area now suffers more with landslides

Lost farmland - Thousands of acres of important farmland is now under water and the new designated farmland has much poorer soil so agricultural productivity is much lower. 

Geological risks - The dam is situated in an area prone to earthquakes which poses an increased risk to the community if the dam failed. 

Economic 

Inefficient energy allotment - the energy produced by this dam may not be used well because China has a very unproductive approach when it comes to power production and supply.