In 1992, under pressure from the environmentalist lobby, Congress passed legislation which mandated an environmental review for all foreign projects in which the U.S. Export Import Bank was involved. The Three Gorges Project became a test case for this new policy. Because of the significance of the project for U.S.-China relations, Ex-Im asked the National Security Council to convene a panel to consider the merits of U.S. participation in the dam. In September 1995, the interagency National Security Council panel delivered its recommendation, signed by the then Deputy National Security Advisor Sandy Berger. The U.S. government, the panel advised, should not "align itself with a project that raises environmental and human rights concerns on the scale of the Three Gorges." But the memo, leaked to Congress, counselled the government to "refrain from publicly condemning the Three Gorges Project." Instead, it continued, "explanation of our policy should emphasize the U.S. government's commitment to strengthening commercial relations with China and to helping China meet its basic energy needs."
Okay, hopefully you are still with me here, I felt it is necessary to give a background on the Dam and the U.S. was going to do it jointly with China for a time, but then backed out.
This from the same link above: The building of the Dam
The construction of the dam, begun in September 1994, will take 17 years from its inception, proceeding in three stages. When the dam is completed, it will have a height, or crest, of 185 meters, placing it somewhat higher than the Golden Gate Bridge. In the early phase of operation, during the third phase of construction, the water level in the reservoir region will be 135 meters, and the final Normal Pool Level, or highest level, will be 175 meters.
The first stage of construction, from 1992 to 1997, involved the building of two phase-one cofferdams to shut off the flow of the river from the construction site, and the re-routing of the river through an artificial diversion channel.
Now during phase two, from 1997 to 2003, the construction of the left bank dam section is under way; the left-bank powerhouse will be completed with the installation of some units, and construction of the spillway and continued construction of the permanent shiplock are taking place. The spillway dam, placed in the mid-section of the structure, is 483 meters long with 23 bottom outlets and 22 surface sluice gates. With a maximum discharge capacity of 102,500 cubic meters per second, the project is able to discharge the maximum level of water possible during floods.
In December 2002, before the flood season in the spring of 2003, the phase-three cofferdams in the diversion channel will be finished, and the reservoir water level will be raised to 135 meters. At this time, the permanent shiplock will be ready for use, and the diversion channel will no longer be needed for navigation. According to the scheme for the second stage, 17 million cubic meters of concrete will be poured, 180,000 metal structures will be installed, and approximately $10 billion will be invested.
The water level will be raised to the 135-meter level, creating the reservoir behind it, stretching 600 km back to the city of Chongqing. Construction will continue on building the right bank dam and the second power plant.
By the end of phase three, the water level behind the dam will be raised to its final 175-meter level. The reservoir formed in the upper river will be longer than the Grand Canyon, with an average width of about 1 kilometer, approximately twice the width of the present river. It will have a total storage capacity of 39.3 billion cubic meters including a flood regulation and storage capacity of 22.15 billion cubic meters.
NOW where some of the Problems and Controversy Lay with the Dam. Still from the same link – but I will be adding other links and somewhat producing the same material – but in a different way – a little later. This was written awhile back.
A great deal has been made of the need to resettle as many as 1.2 million people from the lower slopes of the gorges, west of Sandouping, which will be inundated to create the great reservoir behind the dam. The opposition to resettlement, from "human rights" groups to environmentalist groups, has devoted thousands of pages of articles to the plight of the farmers in this region, and the failure of the government to adequately provide a new life for them. There have even been warnings that dissatisfied peasants may rise up in violent revolt against the authorities.
Here comes some of the “silt/sediment” part – though in all the other reports the sediment build up every year is 700 million tons.
In addition to making the most important environmental improvement—changing the lives of the people—the Three Gorges Dam is part of an overall policy to improve the environment of the Yantgze Valley, including the control of the approximately 500 million tons per year of silt that course down the river.
The possibility of the collection of silt in the huge reservoir to be created by the dam has been a main objection by the dam's opponents. Problems of silt buildup at the Aswan Dam in Egypt, and others around the world, have added to this concern. According to the Chinese, extensive and detailed studies on sedimentation in the reservoir region began in the early 1950s, and concern has increased, as the existing reservoirs and water diversion areas have been filling with silt.
Based on more than 40 years of observations, sediment discharge averages about 526 million tons per year.
The above link and everything in it was written awhile ago and is TOTALLY behind and supports the project. So I have linked and presented excerts from a “pro” Three Gorges Dam writer.
Link to many construction photos of the dam
Satellite Pictures of the Dam taken in 2003
Now lets take a more serious look at the dam, now that it is basically complete and the problems/controversy that has ensued during the construction of the dam – and what has shown up as a result of the dam being built. This is where everything starts getting dicey and why there are very serious and valid concerns about the Three Gorges Dam.
The Three Gorges Dam was completed in 2006 on the Yangtze River, and NASA has released images of the flooding reservoir behind the dam which has displaced 1.2 million people.
[edit on 20-7-2009 by questioningall]