AnaerialviewoftheMaozhouRiverinShenzhen,Guangdongprovince,lastmonth.QIUQUANLIN/CHINADAILY

XiaZheshunwashappytotakehiscanoeingteammembersbacktoShenzhen,Guangdongprovince,afterwatersinthecity"sMaozhouRiverwerequalifiedtohosttrainingforthesport.

"WehadbeentrainingforquitealongtimeoutsideShenzhenasthewaterqualityinthecity"sriverswastoolowtomeettrainingstandardsoverthepastseveralyears,"saidXia,headoftheShenzhenSportsWorkTeam.

AccordingtoXia,allathletesonthecanoeingteamwillbegintraininginAugustatawatersporttrainingcenterthatwasbuiltinawetlandparkneartheMaozhou.

"IneverexpectedthatsuchawonderfultrainingcenterwouldbeestablishedhereinShenzhen,"hesaid.

Thecenter,whichincludesadock,rowinglanes,housesandacanteen,wasbuiltafterwaterqualityimprovedsignificantlyduetofouryearsoftreatmentattheonce-pollutedriver,accordingtoXia.

Withalengthof41.6kilometers,theMaozhouisthelargestriverrunningfromsoutheasttonorthwestinShenzhen.Itusedtobeoneofthemostpollutedriversinthecity,duetosevereindustrialpollutionandsewagefollowingurbanexpansionoverthepast30years.

"Theriverwassmelly,lookingmorelikeascarinShenzhensome20yearsago,"recalledXiaashewatchedhisrowersintheriveronasunnydayinJune.Alongtheriverbanks,manyresidentsweretakingwalks,withwhitecranesflyingabovegreentreesandgrassinthenearbywetlandpark.

Overthepastfouryears,localauthoritieshavedevoted120billionyuan($16.9billion)totreatheavily-pollutedriversinShenzhen,whichhasleadtoenhancedlandscapeinthesurroundingareas.

Inthecity"sBaoandistrict,aninvestmentofmorethan40billionyuanwasusedtobuildsewagetreatmentfacilitiesinthepastfewyears.

"Wehavebuiltseparatepipesystemsforrainfallanddomesticwastewater,whichhaveincreasedthetreatmentcapacityofsewage,"saidJingMou,deputygeneralmanageroftheMaozhouRivertreatmentheadquartersofthePowerChinaEco-EnvironmentalGroup.

Since2016,smallworkshopsandhigh-levelpollutingfactoriesalongthebanksoftheMaozhou,whichrunsthroughmostofBaoan,havebeenshutdownbylocalenvironmentalprotectionauthorities.

Moreover,eightnewsewagetreatmentplantshavebeenestablishedinBaoansince2018,helpingtoincreasesewagetreatmentcapacityto1.04millionmetrictonsperday,accordingtoJing.

ZhengCaijuan,a40-year-oldresidentwholivesneartheMaozhou,oftenbringsherchildrentowalkalongthebanksoftheriveronweekends.

"Welikewalkinginthewetlandparkneartheriver,"saidZheng,whohadmovedtoanearbyresidentialcommunityin2010."Theriverwastoosmellytoallowustoopenwindowsatthattime."

YaoRen,PartychiefofBaoan,saida255-kmgreenwaynetworkwillbebuiltalongriversrunningthroughthedistrictinthenearfuture.

"Theecologicalenvironmentalongtheriverswouldbedramaticallyimproved,followingthedevelopmentofgreenwaysandwetlandparks,"Yaosaid.

"Animprovedecologicalenvironmentshouldbecomepartofawell-offsociety,allowinglocalresidentstohaveabetterlivingenvironment,"hesaid.