The South to North Water Transfer Project (SNWTP), China
South–North Water Transfer Project Central route starting point taocha in Xichuan County, Nanyang, Henan By Nsbdgc (Own work) [CC BY-SA 4.0 (http://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons
The South to North Water Transfer project is an example of a large-scale water transfer scheme. It is one of the largest engineering projects ever undertaken and has both advantages and disadvantages.
Why is water transfer needed?
The Chinese government is currently building a $62 billion South-North Water Transfer Project. The aims of the project are to divert 44.8 billion cubic meters of water per year from the Yangtze River in southern China to the Yellow River Basin in arid northern China. This will move water from humid areas where water supply is sufficient, to drier areas where demand exceeds supply.
The reason the water is needed is because much of China’s economic growth has occurred in the north on the North China Plain around the cities of Tianjin and Beijing. There are 600million people in the North China Plain working in heavy industries that need water and reliant upon agriculture that needs water for irrigation. Northern China has long been a centre of population, industry and agriculture and with all three growing quickly, the regions limited water resources are under pressure.
In Beijing, groundwater is the main water source ( two thirds of all water comes from groundwater in Beijing) for everything from industrial and agricultural use to household consumption. It is estimated that the capital requires 3.5 billion litres of water per year. As the water is taken from the soil, the now-dried up soil compacts. As a result Beijing is sinking on average 5cm a year! (source)
Water Stress and the SNWTP
What does the scheme involve?
The SNWTP China is the largest water diversion/transfer project ever undertaken. It has already taken 50 years to plan and begin construction, and won’t be finished until 2050. It was first thought of in 1952
When finished, the work will link China's four main rivers – the Yangtze, Yellow River, Huaihe and Haihe – and requires the construction of three diversion routes, stretching south-to-north across the eastern, central and western parts of the country.
Eastern route of water diversion project
This diversion will be slightly over 1,155km long and was completed in 2013. It provides water from the Yangtze river to Shandong Province and other areas to be used for domestic and industrial use.
The central route diverts water from the Danjiangkou reservoir on the Han River via new canals to flow through Henan and Hebei Provinces to Beijing – a diversion route totalling some 1,267km in length. It opened in 2014 after delays and the building of the dam at Danjiangkou displaced 300,000 people. Wildlife and farming practises have been disturbed by the central route.
Construction of the western route involves working on the Qinghai-Tibet Plateau between 3,000m–5,000m above sea level is in the planning stages and will involve overcoming some major engineering and climatic challenges. Once completed in 2050, the project will bring 4 billion cubic metres of water from three tributaries of the Yangtze nearly 500km across the Bayankala Mountains and then on to northwest China. This will have huge financial and environmental costs. In addition, the proposed route is in an earthquake zone which poses even more problems.
What are the advantages and disadvantages of the project?
The complete project is expected to cost $62bn, an astronomical cost and more than twice as much as the country's controversial Three Gorges Dam. It will also displace hundreds of thousands of people. An estimated 330,000 people were recently being relocated for the expansion of the Danjiangkou reservoir and carried out against the resistance of affected people.
An advantage is that it should stop the over-withdrawal of groundwater and supply more water to industry, cities, and China's breadbasket in the north. This may stop the subsidence experienced in Beijing because of over abstraction of ground water. The project should also help with helping China cope with climate change, water pollution, and frequent droughts. These all exert huge pressure on major northern cities such as Beijing and Tianjin. The project will move almost 45billion cubic metres of water to help industry and farming in the north.
One issue is that recent droughts in the SOUTH have shown that at times Central China has no excess water that could be transferred to the thirsty North. In the spring of 2011, water levels in the Han River and Danjiangkou reservoir fell so low that people did not have sufficient water for drinking and sowing their crops let alone for sending to Beijing.
There are also concerns that the project could make water pollution problems worse. Pollution from factories along the Eastern Route may make the water unfit to drink. Some experts argue that conservation and increasing water use efficiency can help mitigate China's water problems without jeopardizing the environment displacing large population groups. The Chinese government has put in place around 260 projects to reduce pollution and help ensure that water in the areas of the diversion project will meet minimum drinking standards. These projects have cost $2billion!
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