Using this type of comparison it is possible to see the development of the project to build the dam. Another aim of these images is to promote the opportunity to download Landsat data through the ESA portals , where images captured every day are made available in near real time to the users and the scientific community.
View large format slider. Three Gorges Dam, China. The Project. View large image. Nightmare memories have been revived of , when severe floods left more than people dead and caused extensive economic damage. In response to the build-up of floodwaters upstream, authorities have been discharging large amounts of water from the dam. The swell of water caused by upstream flooding reached 55, cubic meters per second late last week, exceeding the official warning level of 50, cubic meters.
The emergency discharges have inevitably exacerbated flooding in areas downstream from the dam. Massive flooding along the Yangtze is nothing new for China. In , more than 3 million people died during a huge flood in one of the worst natural disasters of the 20th century.
Nevertheless, the current situation is the first major test that the Three Gorges Dam has been put to. There is no reason to think that the structure of the dam itself is under threat. Indeed, the dam was designed to help cope with floods along the Yangtze. Nevertheless, it is safe to assume that the Chinese government is monitoring the situation nervously, hoping that the emergency will soon pass.
The Three Gorges Dam has been a major showcase project for China. View the discussion thread. Upstream from the dam, officials in the city of Chongqing, in Sichuan province, evacuated almost , residents before the flooding. On Thursday, levels along the Yangtze near Chongqing reached heights not seen since , when the country experienced its worst floods in a century, leaving 1.
In Chongqing, roads, bridges, parks and a main highway in the commercial district were flooded, affecting , people and damaging at least 20, businesses, according to officials. Images showed flooding had submerged three-metre-high signs and buildings several storeys high.
Firefighters were using boats to transport trapped residents. A m-high permanent ship lock with 14 turbines was built on the southern bank. In the final phase, the dam was raised to a maximum height of m and an additional 12 turbines were installed on the northern bank of the Yangtze River. A single way one step ship lift system was built at the project complex.
The maximum lifting height is m and the maximum lifting weight is 11,t. The spiral casing began on 26 May The spiral casing installation was finalised for the generating Unit 27 in May This completed the spiral casing of all six underground generating units.
The first 14 generators became fully operational in October , generating 9,MW at a water level of m. The first No. All 24 generators and two power generators were switched on in June They produced 16,MW of power, less than the maximum capacity of 18,MW. The plant reached its full capacity for a short duration in August due to elevated upstream water levels and river flow during floods. The dam will disrupt heavy silt flows in the river and could cause rapid silt build-up in the reservoir, creating an imbalance upstream and depriving agricultural land and fish downstream of essential nutrients.
Environmentalist and political opposition to the Three Gorges Dam was intense. The most emotive issue was the forced relocation of 1. China referred to the detailed plans as improving the lives of those affected, but residents complained about the resettlement funds and job retraining promises being denied. Farmland that will be flooded is more fertile than the higher ground, and approximately 1, factories will be submerged.
Opponents of the Three Gorges Dam had more success outside China. The World Bank, stung by vicious criticism of other hydro projects it sponsored, decided not to fund the project.
It hoped to gain further environmental information from the Chinese, which would allow for a positive decision. It was not against the project. Moreover, its stance did not prevent US groups from bidding for contracts, nor US commercial banks from financing their operations.
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