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Courtesy of IEEE’s Spectrum magazine, a detailed look at China’s ambitious plans to address its water scarcity issues:
“…In 1952, Mao Zedong visited the great rushing rivers of China’s south and suggested that the thirsty north “borrow” some. Thus was born the South-to-North Water Diversion Project.
Nearly 60 years later, construction is under way on the biggest water redirection scheme in history. When complete, the US $62 billion project will transport 44.8 million megaliters of water per year from the lush river valleys of the south to the parched industrial north—enough to flood Beijing to a height of almost 3 meters. The three-pronged project, which consists of an eastern route, a western route, and a central route, includes the construction of more than 1800 kilometers of pipelines and reinforced canals, at least 23 pumping stations, up to 7 dams, and 2 massive tunnels under the Yellow River. Some parts won’t be finished until midcentury.
The northern need for water is great. According to a 2005 report from the China Institute of Water Resources and Hydropower Research, northern China is home to about 44 percent of the population but has only 14 percent of the water. In the northern industrial city of Tianjin, the destination of the project’s eastern route, the amount of freshwater available per capita is well below 1 ML annually, the level most water experts consider essential to meet basic needs.
What’s more, Chinese industry is concentrated in the north, as is the energy production that drives it. China’s thermoelectric power plants will need 82 million ML of water per year by 2030.
Such a big project will have big consequences. Draining one river to fill another, as the western route does, will upset the balance of power—literally—in the string of hydroelectric dams along the Yangtze River. And some destinations, such as Tianjin, don’t even want the water, because of its high cost and poor quality.
Officials can’t even claim that the project will meet the north’s needs. â€In the short term, it might ease the water shortage in the north,†says Ma Jun, director of the Beijing-based Institute of Public and Environmental Affairs. But in the long term, Jun says, conservation and efficiency measures must help solve China’s water crisis.
China’s Central and Eastern Water Routes
CENTRAL ROUTE: The source of the central route, the Danjiangkou Reservoir, has reportedly shrunk due to decreased flow from the Han River. To enable it to send more water north, Danjiangkou is being expanded to a storage capacity of 29 million megaliters. This would mean raising the water level from 157 to 170 meters and relocating 330 000 people who live or work in the floodplain. But increasing the reservoir’s size won’t make more water flow into it from the Han.
Length: 1415 kilometers
Throughput: 12–14 million ML/year
Construction period: Began 2003; missed targeted 2008 and 2010 completion; rescheduled for 2014
Energy consumed: 0 megawatt-hours (gravity powered)
Latest news: As of February, 4500 residents had been relocated to make way for reservoir expansion. The relocation is set to be completed by 2012.
EASTERN ROUTE: Tianjin has reportedly refused to accept water from the eastern route, claiming that it will be too polluted. The city has instead invested in seawater desalination, which now supplies it with 200 megaliters of freshwater per day; this amount should rise to 500 ML within five years. Desalination could be cheaper than eastern route water; according to officials, it costs about 5000 yuan (US $732) per megaliter to desalinate water in Tianjin, while estimates for the piped water are about 18 000 yuan per megaliter.
Length: 1156 kilometers
Throughput: 14.8 million ML/year
Construction period: Began 2002; missed targeted 2007 completion; rescheduled for 2013
Energy consumed: 8.9 million MWh/year from 30 pumping stations between the Yangtze River and the Yellow River; 0 MWh/year from the Yellow River to Tianjin (gravity powered).
Latest news: In March, the first 585-meter-long tunnel for crossing under the Yellow River was completed.
China’s Western Water Route
To refill the dwindling Yellow River from the headwaters of the Yangtze, the western route will require tunneling through mountains, crossing earthquake fault zones, and traversing the 3- to 5-kilometer-high Qinghai-Tibet Plateau. The project will also need new pumping stations and massive dams. The plans, still in the works, are drawing fire from engineers and environmentalists both inside and outside the Chinese government. One of the many concerns is that siphoning water from the Yangtze will likely cause hydropower shortages—around 70 stations supply 770 million megawatt-hours of electricity annually along the Yangtze. One estimate puts the annual energy loss after water diversion at 111 million MWh per year.Length: Unknown; government feasibility study continues
Throughput: 17 million ML/year
Construction period: 2010 to 2050
Energy consumed: Unknown
Latest news: The western route is slated to break ground this year, but no firm date has been set.