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WaterPollutionThreatensNorthwestChina

Nearly80percentofthepopulationinnorthwestChinaarelivinginanenvironmentwithseriousormoderatewaterpollution,accordingtoarecentreportbytheChineseAcademyofEngineering.

Thereportcharacterizedwaterpollutioninthisregionintothreecategories:serious,moderateandclean.

Seriouslypollutedareasinclude:sectionsofthemainstreamsoftheYellowRiverandWeiheRiver,theShuleRivervalleyandYiliRivervalleywhere21majorcitiesarelocated.Waterintheseriversisnotusableevenforirrigationpurposes.TheWeiheRivervalleyhasbecomeoneofthemostseriouslypollutedareasinthecountry.Thepollutedsectionsoccupyonly13%ofthetotalareaofthenorthwestregion,buttheyareindustrialandminingcentersandhometo55.2%oftheregion’spopulation.MajorpollutantsintheseareasareCOD,BODandammoniaandnitrogen.InthemainstreamoftheYellowRiverinGansuandInnerMongolia,heavymetalshavealsobeenfound.

Moderatelypollutedareasare:14cities/districtsincludingUrumqi(Xinjiang),Baiyin(Gansu)andTongchuan(Shaanxi).ThewaterqualityintheseareasismeasuredasmeetingGradeIVstandards.Occupying27.2%oftheregion’stotalarea,thepollutedwatersaffect23.9%oftheregion’spopulation.Waterintheseareasmeetsrequirementsforirrigationbutnotqualifiedfordrinking.Ifunchecked,theywilljointheseriouslypollutedareassoon.

Notyetpollutedareascover27cities.Althoughtheyaccountfor59.8%oftheregion’stotalarea,mostofthesecitiesarelocatedinthedesert,coveringonly20.9%oftheregion’stotalpopulation.