Water takes the express route to Xinjiang
The South-North Water Transfer Project (南水北调工程) is a major infrastructure project designed to bring water resources from the Yangtze River in the south to the Yellow River in the north. The project is not without controversy, but water scarcity in the northern part of the country has kept it moving forward for decades.
A new proposal to divert seawater to Xinjiang promises to be an even thornier issue. Here’s a summary of the project from Xinjiang Daily’s report on a conference held on November 5:
The summit’s basic ideas on the subject of “Moving Seawater West; Bringing Bohai to Xinjiang” were as follows: At the northwest shore of the Bohai Sea, raise the seawater to a height of 1,200 meters above sea level and send it to the southeast part of Inner Mongolia Autonomous Region. From there, skirt the foothills of the Mazong mountains and enter Xinjiang. The tentative plan is intended to fill salt flats, saltwater lakes, and structural basins with large quantities of seawater to form man-made seawater rivers and lakes, thereby suppressing the desert. At the same time, a large quantity of seawater will naturally evaporate under the abundant sunlight of the northwest, becoming moist air that will humidify the northern climate and provide a source of increased rainfall, thereby achieving the goals of controlling the country’s deserts and dust storms and completely transforming the poor ecological environment of the northern and western regions.
Yaxin Online provides more information from the experts involved:
“Taking advantage of Xinjiang’s geography, high in the east and low in the west, along with existing rivers, the seawater will flow naturally once it has been brought to Xinjiang. And power plants can even be set up in areas with large drops in terrain as a hedge against early investment costs.” Huo Youguang, a professor at Xi’an Jiaotong University’s Center for Environment and Modern Agriculture Engineering and one of the authors of the plan to move seawater west, said it would advance the cause of Xinjiang ecology, particularly in the development of the coal chemical industry.
According to Huo, water taken from the Bohai Sea near Tianjin would be sent through sets of pipes to an elevation of 1,280 meters above sea level. One ton of water raised 200 meters requires 1 kWh of energy, or 6.4 kWh for the full 1,280 meters. Then, using anti-seepage canals and small-scale step-up works (such as reservoir ponds to increase elevation) to extend the natural flow distance, the water will reach the Shulei River near Yumen, Gansu, by way of Huangqihai Lake. Then, using the westward flow of the Shulei River, it will flow naturally into the eastern border of the Tarim Basin at Lop Nur.
“The biggest questions in the Moving Seawater West project are whether the water can be used, and how to resolve the issue of cost,” said Yang Kailin of the China Institute of Water Conservancy and Hydro-Electric Power. He said semi-permeable membranes would be used to remove the salt, a method that has the advantage of conserving energy. Producing the same quantity of water by distillation requires 40 times the power....Yang said that there is currently no “bottleneck” for desalinating water in China. The project can employ reinforced plastic piping that is impervious to corrosion by seawater. Using 8-meter pipe, the cost for sending a ton of water to Xinjiang would be around 8 RMB.
The first stage of the project is expected to require 62.8 billion RMB (56.7 billion for construction), and one expert predicted that it could be realized within six years.
Oddly enough, commentators in overseas forums were discussing the project earlier this year using phrasing quite similar to that found in today’s articles. There were some notable differences, however. Writing for the Hong Kong daily Ming Pao in March, columnist Zhang Li concluded:
This massive engineering project will require forty years to complete, at which point it will transform the ecology of China, vastly improving the living conditions for the Chinese people and bringing prosperity to their descendants. Reportedly, comprehensive talks on the plan are now in progress.
Update (2010.11.16): Probe International is reporting that some Chinese scientists have cast doubt on the feasibility of the project.
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