Yang: 【1】Basic Introduction to The Three Gorges Dam Project

The China Yangtze Three Gorges Dam Project, the largest water conservancy pivotal project in the world today, is located in the middle part of Xiling Gorge. This project can fully exploit the hydraulic resources in the Three Gorges of Yangtze River. It is beneficial in ten aspects, including flood control, power generation, navigation, aquaculture, tourism, ecological protection, environmental purification, developmental resettlement, transferring water form the South to the North, water supply and irrigation which makes it a unique super power station worldwide.

It consists of three major structures, including the dam, the powerhouses and the ship locks. The dam is 2309.47 meters (6,929 feet) long, with the crest at elevation 185 meters (555 feet). The normal pool level of the reservoir is EL 175 meters (525 feet) and the total storage capacity 39.3 billion cubic meters (1,061 billion cubic feet) of which 22.15 billion cubic meters (598.00 billion cubic feet) is for flood control. So the dam can effectively hold up the flood from the upper reach of the Yangtze River and improve the flood control capacity of the middle and lower reaches. The powerhouses have been equipped with 26 units of generators of 700,000 kw each, with a total capacity of 18.2 million kw and annual output of nearly 84.7 billion kwh.

The dam has been equipped with twin 5-flight ship locks, which can adequately handle tows up to 10,000 tons, and one-step vertical shiplifts, which can provide immediate service for any vessels under 3,000 tons.  The dam will elevate the water level of the upper reach of the Yangtze River of 80 metes (240 feet) in the flood season and 110 meters (330 feet) in the dry season. So it can improve the navigating route in Sichuan Province of 660 kilometers (375 miles) and increase the shipping capacity from 10 million tons to 50 million tons.

This photo taken on Sept. 14, 2012 shows the night scene of the Three Gorges Dam  which spans China's Yangtze River, to reduce water discharge with a full-capacity storage test. The reservoir, mainly built to tame the Yangtze River, usually discharges water in May. It alleviates spring droughts in areas downstream, and makes room to contain water from the river's seasonal flooding in summer. (photo: Zuyu Chen)

Reference:

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