Desalination

Figure 1: Bohai Bay Plant site near industrial city of Tangshan 

Source: Yiting Sun, 2016

The picture above shows the site for a proposed new seawater desalination plant. This plant, costing $1.1 billion, is located 200 km southeast of water scarce Beijing and will have the potential to provide for one third of the capitals total household water needs via a pipeline direct to the city (Larson,2015). The facility, which is located in Bohai Bay, was originally supposed to be completed by 2019 and is intended to help China reach its 2020 target of achieving a desalination capacity of three million tons of fresh water per day (Sun, 2016).

This was what the government intended in 2014, but since then progress on the project has been limited. While it has secured approval from regional and national governments and is still held up as one of China’s major initiatives to help battle water scarcity in the north, major construction on this project is yet to begin.

After some early success in desalination, with China managing to increase its desalination capacity by 70% yearly from 2006 to 2010, they began to miss targets and progress slowed (Gleick, 2013). In 2014 they produced 2.2 million tons of desalinated water a day, just missing their target of 2.6 million tons and then by the end of 2015 their capacity had dropped to just 1.03 million tons a day (Larson, 2015).

This is an issue that demands immediate attention as government stats suggest that by 2030, costal areas will have water shortages totalling 21.4 billion cubic meters (Sun, 2016). China however faces many challenges in order to improve its desalination capacity. One of which is the energy intensive nature of desalination that results in desalinated water being both environmentally and economically expensive. As a result building large desalination projects is not the most attractive prospect for local governments and residents who are forced to pay high prices for their water. Wang Zhi, director of desalination technology says that “When there is a drought, local officials and enterprises all come to see us and say, ‘We want to desalinate seawater, but if there is sufficient rainfall the next year, they will drop the idea and invest their money in other things first.”

Demand then for new projects is inversely proportional to fluctuations in ground and surface water resources. If for example natural water resources are high then seawater desalination projects are often put on hold.

A new policy was introduced a few years ago by the Chinese government in an attempt to prioritise freshwater resources. It stated that in certain costal areas new industrial facilities which are deemed water intensive may not make use of local surface water resources but will have to provide their own. This is why 60% of the water produced by desalination is used in industry (Walker, 2015).

The South North Water Diversion Project that I discussed in my previous post has reduced the importance of desalination projects in the north. But the many drawbacks of the mammoth diversion project have caused some environmentalists and academics to question the sustainability of the project that has displaced thousands and caused an unprecedented level of environmental destruction. The choice between water transfer and desalination is complex, as any major new desalination project must also be designed to minimise its environmental impact. The director of the Centre for Clean Water and Clean Energy at MIT, John Lienhard, claims that this can be achieved by “diluting and diffusing the concentrated salt water discharged back into the sea after the fresh water has been extracted”.

While this process of desalination may help increase the water resources of the dry north it comes at a considerable economic and environmental cost. This then begs the question of whether this is yet another one of China’s grandiose engineering projects that they are so fond of. Is desalinating water the solution to China’s crisis? Probably not, it’s just not a sustainable practice; the plants just put too much stress on local ecosystems and increases the demand for water and coal. Many critics claim that major projects such as these distract from the more important goals of improving conservation of resources, efficiency and cutting carbon emissions (Watts, 2011).