Polluted Water Challenges China’s Engineering Efforts

Memo #114

(The third Memo from the Theme, Water, Scarcity, and Tibetan Plateau Frontiers)

By Darrin Magee – magee [at] hws.edu

Water is central to China’s environmental challenges. While not water-short overall, the geographic and temporal variations in China’s precipitation are extreme. Some areas suffer from dangerously lower per capita fresh water availability. Water conservation innovation does happen, but shortages usually elicit familiar engineering responses such as dams and diversions. Most notable is the South-North Water Transfer Project (SNWTP), which aims to take nearly 45 cubic kilometres (45 billion cubic metres) of water annually from the water rich Yangtze River basin to water scarce regions around the Yellow River basin in the north. The diversion would essentially replace the Yellow River’s total annual runoff of 30 billion cubic metres.

Transferring the water may be the easy part; rendering it safe and restorative for human and non-human needs could become the real challenge. China has five water quality grades, with grades one through three considered safe for human consumption. A 2008 Ministry of Water Resources report concluded that 70 per cent of monitored urban surface waters were polluted beyond grade three (unfit for direct human use). More troubling were the groundwater findings: 74 per cent of wells sampled in eight regions were polluted beyond grade three. Thus even in areas where water is not lacking in absolute terms, intense localized pollution renders those waters essentially useless, creating a condition of “quality-induced scarcity.”

Since its inception, the SNWTP has been beset by problems and technical challenges. Some were expected, such as the need for over 20 pumping stations to lift water to higher elevations along the eastern route. Others were not so readily apparent, such as the extent of the quality-induced scarcity problem. Yet the logic is straightforward: SNWTP waters will pass through some of the areas that have seen the most rapid and intensive economic development in the past two decades, and the pollution impacts of that development are widespread and serious. Plans now call for more than 100 wastewater treatment plants to be built along the eastern route (most of which occupies ancient Grand Canal waterways). Those plants require electricity, and producing electricity requires water, creating a potential choke point.

About the Author:

Darrin Magee – Assistant Professor of Environmental Studies, Hobart and William Smith Colleges. Director of Asian Environmental Studies Initiative.