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Water Pollution ThreatensNorthwest China
Nearly 80 percent of the population in northwestChina are living in an environment with serious ormoderate water pollution,according to a recent reportby the Chinese Academy of Engineering.
The report characterized water pollution in this regioninto three categories:serious,moderate and clean.
Seriously polluted areas include:sections of the mainstreams of the Yellow River and Weihe River,theShule River valley and Yili River valley where 21major cities are located.Water in these rivers is notusable even for irrigation purposes.The Weihe Rivervalley has become one of the most seriously pollutedareas in the country.The polluted sections occupyonly 13%of the total area of the northwest region,but they are industrial and mining centers and hometo 55.2%of the region’s population.Major pollutantsin these areas are COD,BOD and ammonia andnitrogen.In the main stream of the Yellow River inGansu and Inner Mongolia,heavy metals have alsobeen found.
Moderately polluted areas are:14 cities/districtsincluding Urumqi(Xinjiang),Baiyin(Gansu)andTongchuan(Shaanxi).The water quality in theseareas is measured as meeting Grade IV standards.Occupying 27.2%of the region’s total area,thepolluted waters affect 23.9%of the region’spopulation.Water in these areas meets requirementsfor irrigation but not qualified for drinking.Ifunchecked,they will join the seriously polluted areassoon.
Not yet polluted areas cover 27 cities.Although theyaccount for 59.8%of the region’s total area,most ofthese cities are located in the desert,covering only20.9%of the region’s total population.