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December 12th, 2014
Via the Financial Times, an update on China’s South-North Diversion Project:
©EPAFishermen in front of the Danjiangkou dam
China officially inaugurated one of the world’s largest and most controversial engineering projects on Friday as water from the Yangtze River valley finally arrived in the parched capital, Beijing.
The $60bn South-North Water Diversion project will eventually bring an annual 44.8bn cubic meters of water — equivalent to a second Yellow river — from humid central China to the North China plain, where state-sponsored heavy industry, rapidly growing cities and heavy dependence on irrigation are severely depleting underground water supplies.
“Our goal is to preserve economic development and preserve the ecology,” Shen Fengsheng, chief engineer for the project at the Ministry of Water Resources, told the Financial Times in October. Increasing water supply from the south should alleviate “funnels” — large areas where the ground is subsiding because of the depletion of underground water.
Opposition to the project centres on its size and expense, the displacement of up to 400,000 people, and concerns it will exacerbate growing shortages of water in the middle of the country. Environmentalists believe large water-transfer projects allow China to avoid adopting more water-saving measures, including pricing reform and better technologies.
“Each time when ideas are exchanged and people engage in a battle of opinions, the research and policy making will be more sufficient and scientific, and the hard issues will become clearer,” the official People’s Daily newspaper said this week, in a veiled allusion to the controversies surrounding the project.
The water that officially began flowing on Friday coursed through the so-called central route. The Danjiangkou reservoir in Hubei province was expanded so water could flow via canals and tunnels to the North China plain, including Beijing.
Technically, the most difficult part of the project was stabilising the soil to prevent the canal walls from caving in. Engineers visited major US water transfer projects but the American solution of coating the walls with lime caulk turned out only to work on some types of soil. The Chinese team had to sink supports into the ground and inject concrete into the swelling soil in some portions, Mr Shen said.
A second challenge was raising the level of the Danjiangkou reservoir, by constructing a second dam to encase the original dam. The two were attached to allow for seasonal expansion and contraction of the concrete.
The eastern route, bringing water from the mouth of the Yangtze River to the northern port city of Tianjin, is already partially in operation.
The western route, the most ambitious of the three, would drill through the Tibetan plateau to divert water to the Yellow river, which irrigates most of the north China plain. The completion of the eastern and central routes has given new ammunition to those who say the western route is needed for industrialisation of China’s arid northwest.
