Demolition of the last cofferdam protecting the main wall of the
Three Gorges Dam, the world's largest water conservation project,
was completed successfully on Tuesday afternoon in the middle
reaches of the Yangtze River. The removal of the cofferdam means
the main wall of the Three Gorges Project has formally begun its
role in flood control two years ahead of schedule.
According to a report published on the official website of China
Three Gorges Project Corporation, the project contractors, the dam
has set the following 10 world records:
1.?Most distinct flood control function: The Three Gorges
Reservoir has a total storage capacity of 39.3 billion cubic
meters, of which 22.15 billion cubic meters is for flood control.
The flood-discharging function of the dam can reduce a flood peak
by 27,000 to 33,000 cubic meters per second, effectively
controlling floods in the upper reaches of the Yangtze River and
safeguarding the lives of 15 million people and 2.3 million
mu (6 mu=1 acre) of farmland in the lower reaches
or Jingjiang area.
2.?Largest hydropower plant: The total installed capacity
of the Three Gorges Hydropower Plant is 18.2 million kilowatts with
an annual electricity output of 84.68 billion kwh.
3.?Water conservation construction on the largest scale:
The total length of the dam axis is 2,309 meters. The spillway
section is 483 meters long. There are 26 turbine generator sets
with a per-unit generation capacity of 700,000 kw. The lock is a
double-way five-step shiplock.
4.?Shiplock with the most steps and highest hoisting
distance: The double-way five-step lock has a hoisting distance of
113 meters.
5.?Most complicated shiplift: The dimensions of container
portion of the shiplift are 120 × 18 × 3.5 m, with a tonnage of
118,000 tons of water and 3,000 tons of other material.
6.?Water conservation project involving the most
construction: The entire project involved the excavation of 134
million cubic meters of earth-rock for the main structure, and the
placement of 27.94 million cubic meters of concrete. 46,300 and
256,500 tons of reinforcement bars and metal structures
respectively were installed.
7.?Most difficult water conservancy project in 2000: The
concrete placement of the project in 2000 was 5.4817 million cubic
meters, with monthly maximum placement reaching 550,000 cubic
meters.
8.?Largest flood discharging capability during period of
construction: The damming capacity of the project was 9,010 cubic
meters per second, the maximum flood peak discharge measuring
79,000 cubic meters per second.
9.?Highest maximum flood-discharge capacity: The spillway
has a discharge capacity of 102,500 cubic meters per second.
10.?Most complicated resettlement project: As many as 1.13
million people would have been resettled as a result of this
project.
?(China.org.cn by Wang Qian, June 7, 2006)