1. The proposal for the construction of the Three Gorges Dam was first proposed in 1919. The person who issued the proposal was Sun Yat Sen who was a forerunner of the democratic reform in China. Sun Yat Sen proposed the building of the dam because of the enormous potential that the Yangtze River has. In his view, the dam would have improved the production of energy by far, as well as making it much easier for navigation in the river.
2. The Chinese historians and archaeologists were not happy at all with the proposal for constructing the dam, and even less when the construction actually started. The main reason was that the valley of the Yangtze River is one of the places where the Chinese civilization originated and initially started developing, so the valley had lot to offer for the history and archaeology. The building of the dam meant that thousands of archaeological sites would be under water and very possibly destroyed.
3. As the construction of the dam was about to take on, millions of had to relocate as lot of towns and villages were going to be submerged. The local government officials though weren't very helpful. Instead of helping the people, paying them for the loss of their homes and land, and providing them with shelters, the people were mostly left on their own. This resulted in lot of people to end up living in miserable conditions, homeless, and lot of people unfortunately died because of the terrible living conditions.
4. The building of the Three Gorges Dam was supposed to be done in the best way possible. It was a huge project where everything had to be perfect, both because of the economic benefit and because of the safety for the people living near it. The politicians though didn't really cared about of those two aspects, the safety, and being very corrupted, they neglected the safety issues in order to capitalize and ''fill their pockets''. This resulted in big problems pretty much every year, as millions of people are terribly affected by the Yangtze River when its levels rise, and lot of people end up dead every year.
5. China was not in a very nice place economically, and of the reason for that was that the country was not able to produce its own energy on a large scale. The Three Gorges Dam was seen as a project that can turn things around. It was a big investment, but it was going to produce lot of energy, very cheaply, and can be used for a very long period of time. The initial estimates have been that the dam will be able to increase China's energy production by 10%.
6. The Three Gorges Dam is the dam that produced the most hydroelectric power in the world. It produces 22,500 megawatts. The Hoover Dam for comparison is ranked on the eleventh place for production of hydroelectric power, producing 2,080 megawatts. Despite the initial projections that the Three Gorges Dam will be producing around 10% of the power in China, the fact is that the dam accounts for 14% of the hydro-power in the country, while the whole hydro-power accounts for 17% of the total energy production of China, thus the production is way bellow that the first projections.
7. The Three Gorges Dam has been of great benefit for China's economy, mainly because of the energy production and trade. The dam though also came with some negativity, especially for the environment. The movement of the aquatic animals has been stopped and limited. The flow of the nutrients has also been stopped, resulting in higher concentration before the dam, and much lower after the dam. Lot of species became endangered or extinct. Also, the upper part of the river has become much more vulnerable to floods and landslides, which has caused enormous problems for the local population.
8. The construction of the dam has had multiple negative implications. The biggest worry though seems to be the flood prowess to the upper part of the Yangtze River. The safety measures have not been taken into account, or rather have not been implemented because of corruption among the politicians. This has resulted in the upper flow of the river to be in danger of flooding every time when there is a rise in the waters of the rivers, be it because of intense rainfall of melting of snow, with millions of people being affected badly by it each year.
9. The local communities are in a situation where they both have lot of benefit from the dam and also be heavily affected by the things left out during the construction of it. The local population benefits from the energy production, more jobs available, fertile soil, trade roots, fishing etc. But the local communities also suffer from the dam, as there are lot landslides occurring, and each year there are devastating floods, often having their homes and farmlands destroyed.