Proponents of the project argue that the situation in the north is critical, and that the government is out of options. Some scientists are looking into desalination methods, but such solutions are expensive and inefficient. Others sa y that the government should spend money promoting water conservation, river cleaning, and environmental regulations on polluting companies.
Really, the conflict is between the rural, farmer population and the growing city population. With the government taking more and more from the countryside and giving it to the cities, the standard of living for peasant farmers is decreasing while that of the city residents is increasing. As a result, immigration rates to major cities in China is growing rapidly, magnifying the problem. More people will immigrate to the cities for better work and living conditions, and will consume more resources. If the government’s solution is to take resources from the poor to stem the usage of resources, this problem will feed itself and become a vicious cycle.
Source: http://www.nytimes.com/2011/06/02/world/asia/02water.html?pagewanted=all