Fighting Water Pollution With Data

By Wu Yixiu 21 April, 2010

Greenpeace China’s Wu gives us the hard truth about China’s water problems.

China’s first national pollution census, released in February 2010, revealed that the country may be losing its battle against water pollution. According to the Ministry of Environmental Protection (MEP), in 2007 China’s Chemical Oxygen Demand (COD) discharge, a primary measurement of water pollution, was estimated to be 13.8 million metric tonnes. The recent census however indicates that the figure is in fact more than double and nearer 30.3 million metric tonnes. The increase is mainly due to the inclusion of agricultural effluents into the calculation as well as absolute increases in industrial discharges.

The revelation came as a shock to many, who had previously believed that China’s water problems, while severe, had slowly been improving over the years.

However there is reason for optimism. While the census revealed the severity of China’s water pollution, it also shows the potential that data gathering can have in combating pollution.  Better data improves our understanding of the different factors contributing to China’s COD increase, and how best to tackle pollution. The census also showed the government’s increasing willingness to uphold and prioritise transparent disclosure of environmental information.

The next big step is to go beyond collecting data on COD and expand the scope to capture individual pollutants.  COD, which measures the capacity of water to consume oxygen during the decomposition of organic matter, has been used as the primary indicator to measure water pollution globally. In China, it has been widely used both by the government and the media to disclose organic pollution levels in water bodies.

However, COD has its limitations. It can only account for the volume of organic chemicals that exist in water, but it does not reveal the specific pollutants released and present in water. Without knowing which pollutants are being discharged, it is extremely difficult to draft policies that control and abate the dangers that specific pollutants may pose to the environment and society.

In fact, even though the latest census also included figures for nitrogen and phosphorus—the two major pollutants responsible for causing excess algae in Tai Lake for example—this information is still not sufficient to obtain a comprehensive picture of the nature and severity of water pollution in China. For instance, industrial wastewater discharged by thousands of factories into river bodies throughout China is a cocktail of different types of pollutants, many of them hazardous and unfortunately, most of these pollutants are not being tested or regulated by the government.

Greenpeace urges the Chinese government to start collecting data on individual pollutants, in particular persistent organic pollutants (POPs), which include chemicals such as dioxins, polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT). Despite the fact that POPs are some of the largest components of industrial and agricultural pollution, they remain unmonitored.

Factories should provide data

Collecting more data on pollutants obviously requires more resources. How can local governments, constrained by limited budgets undertake such a task?

Central government could help by making it mandatory for factories, one of the biggest sources of water pollution in China, to disclose their wastewater discharge data.

The latest census required two years of door-to-door investigation and involved close to 570,000 government workers. Yet experience from developed countries show that a more effective way of gathering discharge data is for the government to require that factories themselves disclose their pollutant discharge data on a regular basis, thereby shifting the burden of data gathering and disclosure from the government to the factories.

The establishment of an appropriate Pollutants Release and Transfer Register (PRTR), which obliges factories producing or using chemicals to provide the details of their discharges, has changed the way many developed countries and some developing countries around the world combat pollution in their respective countries

Based on the developed world’s experience, the system can provide crucial information when governments are deciding on their countries’ respective chemical management and emissions control policies and contribute to actual reductions in factory pollution discharges. The PRTR system in the US has been credited with reducing pollutant discharges by 61 percent between 1988 and 2007.

Data should be accessible to the public

Not only should the Government make all the details of the census public, it should also strive to establish a strong platform through which the public can easily access a wide range of pollution data.

The release of the national census on pollutant discharges has been viewed as a symbol of the Chinese government’s commitment to environmental transparency. However, it appears that the details of the census, such as the breakdown of pollutants by industry source, have not been made accessible to the public.  Disclosing detailed discharge data to the public enhances the understanding of environmental risks and enables communities to monitor pollution discharges at the local level.

According to MEP, the next comprehensive national census is scheduled in 10 years time. For the next round, the Government should require factories to disclose the required data and ensure the public has access to the information. This would enable China to use data to more effectively combat water pollution.