(March 1, 2013) A new study, published by Probe International, reveals that China’s Three Gorges Dam reservoir has become a cesspool of industrial and urban sewage because of inadequate treatment and the damming of the river. Legal reforms to enforce higher standards and penalties for polluters are the only hope to rein the crisis in.

By Lisa Peryman for Probe International

An investigation into wastewater treatment in the Three Gorges Reservoir Basin has found that increased wastewater effluents and a decline in the flow rate of the Yangtze River, caused by construction of the Three Gorges Dam, are creating a pollution crisis in the 600-kilometre reservoir.

Completed by the Chinese NGO, Chongqing Green Volunteers Association, the authors investigated wastewater treatment in Chongqing, the largest industrial and commercial centre in the southwest of the country. Located along the Yangtze, some 600 kilometres upstream of the Three Gorges mega-dam, the study’s authors zeroed in on how the sprawling metropolis manages its wastewater, which has grown rapidly since the decision to build the dam and promote growth in the region.

To convince local politicians to go along with the Three Gorges Dam, the map of the ancient port city of Chongqing was redrawn to create a regional metropolis and government policy was redrafted to promote the huge new municipality, leading to its exponential growth over the past two decades. In 2006, based on satellite imagery, Britain’s Channel 4 dubbed it the “fastest-growing urban center on the planet.” Also known as the “Chicago of the Yangtze,” Chongqing’s dramatic expansion, and declining environmental health mirror the decline brought on elsewhere in the country by China’s rise.

For thousands of years, residents of a much smaller Chongqing had dumped their garbage along the Yangtze’s riverbanks, which the river would wash downstream during flood season. The creation of the dam’s 600-km-long reservoir, however, backed up and slowed down the Yangtze’s flow, and created a concentration of pollutants, sewage and garbage in the reservoir area. The situation finally forced Chongqing, which sits at the head of the reservoir, to confront how it dealt with waste. But has it coped well?

The study notes that although the Chongqing Municipal Government has invested in more than 40 new large and medium-sized wastewater treatment plants in important cities in the Three Gorges Reservoir Region along the Yangtze River, the decreased flow rate of water caused by the construction of the dam has robbed the Yangtze of its ability to self-purify the organic pollutants. This is especially true in the tributaries, which cannot now be diluted or flushed away quickly by the Yangtze River, leading to serious eutrophication in some tributaries.

Fears that a dammed Yangtze would turn China’s most important waterway into a massive cesspool of urban, industrial and agricultural wastes now seems to be becoming a reality.

According to the study, Metropolitan Chongqing produces 3,000 km3 of wastewater daily, but treatment plants in the region are only designed to treat 1,416.4 km3 of wastewater per day. As such, of the 3,000 km3 of wastewater produced in Metropolitan Chongqing every day, only 2,119 km3, 71% of the average daily wastewater volume produced, is treated.

With much of the waste being dumped directly into rivers, E. coli levels now exceed the normal standard for the Yangtze and Jialing.

In many of the districts that make up Chongqing Municipality, the study found faulty wastewater drainage networks and poor maintenance has led to contamination and low wastewater collection rates. It did find, however, that smaller wastewater treatment plants utilizing wetland biotechnology achieved high rates of treatment efficiency and were well worth promoting, as these facilities have lower overheads and operating costs, and required less space.

While Chongqing continues to develop at a rapid pace, the city’s physical infrastructure lags behind. The study found that there aren’t sufficient resources to meet current needs, let alone those that the city’s wastewater management systems will face. Oversight and law enforcement strength is also lacking. The government – both at the municipal and local level – does not possess the administrative capacity and regulatory clout to properly enforce existing wastewater treatment standards, the study concludes, adding, it is almost impossible, in any case, for governments to regulate themselves due to conflict of interest.

To ensure pollution sources in the region are brought into line, the authors recommend reigning in polluters through market mechanisms, public oversight and the rule of law. They also urge enlisting private-sector capital and technology to meet municipal water needs and price adjustments that reflect the true cost of water.

Read the full study, entitled “An Investigation Into Wastewater Treatment in the Three Gorges Reservoir Basin,” here.

The Chongqing Green Volunteer Association has been working to protect the Yangtze River since the 1990s, with a special focus on water quality in the Yangtze River and the Three Gorges Reservoir area in Chongqing Municipality. It compiled this report under the guidance of Wu Dengming, who has served as the organization’s Vice President, President and Secretary-General.

For more on Wu Dengming, see:
Farewell Wu Dengming, “China’s green hero”
Wu Dengming — The Economist obituary