Globally,　water　demand　is　rising　and　resources　are　diminishing.　Most　of　the　world＇s　water　systems　have　been　highly　successful　in　delivering　high-quality　water　to　large　populations.　However,　most　of　these　systems　also　incur　a　notable　amount　of　loss　in　their　operations.　Water　loss　from　the　water　supply　system　has　long　been　a　feature　of　operations　management,　even　in　the　countries　with　a　well-developed　infrastructure　and　good　operating　practices.　There　is　no　doubt　that　the　sustainable　management　of　water　supply　system　is　a　challenge　for　the　whole　world.　Water　leakage　cannot　be　completely　avoided,　but　they　can　be　managed　so　that　they　remain　within　economic　limits.　Some　new　models　of　water　loss　management　have　been　developed　recently.　As　the　technical　and　economic　levels　varied　in　different　cities,　the　best　practice　using　in　their　water　supply　systems　leakage　control　should　be　taken　suited　to　local　conditions.　In　this　case　study　a　water　loss　management　strategy　for　a　large　city　in　north　China　was　suggested　and　the　technological　means　for　the　optimized　its　managing　were　provided.　The　basic　principles　for　structuring　district　meter　areas　in　this　water　supply　system　according　its　features　were　developed.　The　GIS　as　the　tool　was　used　during　the　study.　Based　on　the　field　test,　the　water　balance　calculations　of　three　DMAs　were　carried　out,　and　using　the　fuzzy　appraisal　method　to　evaluated　their　degree　of　water　losses.　©　2009　ASCE.