October 17, 2002
As concern mounts about pollution in the future Three Gorges reservoir, Chongqing appears to be considering the idea of abandoning the Yangtze River altogether as a source of drinking water. Officials are studying the feasibility of drawing cleaner supplies from smaller rivers in the vicinity, such as the Qi, Wubu and Hou, the Chongqing Morning Post (Chongqing chenbao) reported Oct. 10.
Chongqing municipality is situated at the confluence of the Yangtze and Jialing rivers, both of which have fared badly in annual water-quality tests. According to China’s system of standards, water in the two rivers has been rated as Grade 3 (poor quality, but still suitable for drinking and swimming) and Grade 4 (unsuitable for drinking or swimming), according to the Chongqing Water Resources Bulletin 2001.
The official document lists the main pollutants as E. coli, ammonia-nitrogen compound, phosphorus and petroleum, indicating that the rivers have been seriously contaminated by both industrial wastewater and domestic sewage.
The amount of wastewater discharged in urban Chongqing and upstream areas is enormous. Last year, 2.4 billion tonnes of wastewater from upstream sources entered urban Chongqing, mixing with the 1.4 billion tonnes of polluted water produced by the city itself, the Chongqing Morning Post said.
The municipality is racing to clean up the heavily polluted Yangtze before the Three Gorges dam permanently slows the river’s flow, concentrating pollutants in a 660-kilometre reservoir that will begin to fill in June. A new network of pipelines and wastewater treatment plants is planned for urban Chongqing, though construction has been delayed by citizens’ demands for higher compensation for land, homes and businesses being expropriated for the scheme.
Local water experts warn that even with treatment, it is difficult to completely remove heavy metals and organic phosphorus from water, and that some toxic chemicals are likely to remain.
Meanwhile, Chongqing is banning the sale of detergent products containing phosphorus as of Jan. 1, in a bid to protect water quality in the reservoir, the Chongqing Evening News (Chongqing wanbao) reported Oct. 11.
According to official statistics, about 10,000 tonnes of phosphorus ends up in the Yangtze every year, with 6,000 tonnes of the total pouring into the river in the Three Gorges area. The phosphorus has contributed to the proliferation in the Yangtze of blue-green algae, which can lead to the death of other organisms in a body of water.
Categories: Three Gorges Probe