China is approaching the half way mark of a mega water infrastructure project said to rival the Great Wall in its scope and ambition. Begun in 2002 and due for completion in 2050, the South-North Water Transfer Project aims to address one of China’s biggest challenges: water security.
With a fifth of the world’s population and a sixth of global water resources, water security in China is already an issue and one that worsens when disparities in water access across the vast nation are taken into account. Northern industrial regions are thirsty but it is the south of the country that is frequently flooded.
Redistributing the water on a massive scale is an idea first put forward by Mao Zedong in 1952 and one that is now being put into action. When complete in another 25 years time, the South-North Water Transfer Project will carry billions of cubic meters of water over 4,345 km across the republic.
Three phases, two already in operation
The project has three main phases. The first, already finished in 2014, is a so-called Central Route or “Grand Aqueduct”, reliant on gravity and stretching 1,264 km from the Danjiangkou Reservoir on the Han River, to Beijing. It entailed the relocation of 330,000 people and, critics point out, has already had the consequence of reducing water flow in the Han River.
The second phase is also up and running, though still being worked on. Dubbed the Eastern Route, it is an upgrade to the 5th-century-BC Grand Canal, taking Yangtze River water to northern population centres, like Tianjin. A total of 20 pumping stations move the water along its 1,100 km route.
If concerns about diverting water are a problem for the Central and Eastern routes, they are doubly so for the as-yet-unstarted Western Route, which is designed to take Tibetan Plateau water to Inner Mongolia and elsewhere. Asian rivers that feed regions beyond Chinese borders rise in the Tibetan Plateau, and those regions could be negatively affected by the plateau being exploited, meaning ecological and geopolitical tensions are rising there too.
Disease, danger to aquatic life, and agricultural waste
And competition for water resources is not the only issue. Where water is carried, waterborne diseases can go too. Aquatic life is being impacted as ecosystems change due to changing water levels. Authorities must also work to prevent seawater intrusion into the system, when, some argue, desalinisation plants would be money better spent.
Others have questioned whether the project is necessary at all. If China’s agriculture, which relies on water-guzzling crops and is so inefficient that the nation still imports more food than it grows, were modernised, less water would be needed, Professor Stephan Pfister from ETH Zurich told Interesting Engineering. What’s more, the idea of water metering is yet to really be deployed and urban water infrastructure is dogged with leaks that should be fixed rather than fed. Until they are, the $70 billion being spent on the South-North Water Transfer Project, could prove to be money down the drain.
