Three Gorges Dam is the largest hydropower project ever built. When construction began in 1994, it was designed not only to generate electricity to propel China’s breakneck economic growth, but also to tame China’s longest river, shield millions of people from fatal floods and, as a symbol of technological prowess, become a searing point of national pride.
But it hasn’t quite worked out that way.
For a start, the whole project cost 200 billion yuan ($28.6 billion), took nearly two decades to build, and required uprooting more than a million people along the Yangtze River. And while the government promised the dam would be able to protect communities around its immediate downstream against a “once in a century flood,” its efficacy has frequently been questioned.
Those doubts recently resurfaced, as the Yangtze basin saw its heaviest average rainfall in nearly 60 years since June, causing the river and its many tributaries to overflow.
More than 158 people have died or gone missing, 3.67 million residents have been displaced and 54.8 million people have been affected, causing a devastating 144 billion yuan ($20.5 billion) in economic losses.
Despite the havoc, Chinese authorities claim the Three Gorges Dam has succeeded in playing a “crucial role” in intercepting floodwaters. The dam’s operator, China Three Gorges Corporation, told China’s state news agency Xinhua that the dam has intercepted 18.2 billion cubic meters of potential floodwater. A water resources ministry official told state-run newspaper China Youth Daily that the dam “effectively reduced the speed and extent of water level rises” on the middle and lower reaches of the Yangtze.
But with multiple gauging stations monitoring river flows in the Yangtze basin seeing record-high water levels this summer, some geologists say the limited role of the Three Gorges Dam in flood control has been laid bare.
‘A tea cup for a big tub of water’
The Three Gorges Dam is an awe-inspiring structure.
Firstly, it is one of the few man-made structures on Earth that’s visible to the naked eye from space, according to NASA. Completed in 2006, the body of the dam is immense. It is 181 meters (607 feet) tall and spans 2,335 meters (1.45 miles) across the Yangtze just before the deep, narrow valley gives way to plains.
Then there’s its accompanying hydropower plant, which was completed in 2012 and has a generating capacity of 22,500 megawatts, or more than three times the capacity of the Grand Coulee Dam, the largest in the United States.
But according to the Chinese government’s 1992 proposal, the top reason for building the dam wasn’t power generation, but to prevent flooding.
