Usinggeographicinformationsystemtostudyfloodedareaanddamageevaluationhasbeenahotspotinenvironmentaldisasterresearchforyears.Inthispaper,amodelforfloodedareacalculationanddamageevaluationispresented.Floodingispidedintotwotypes:‘sourceflood'and‘non-sourceflood'.Thesource-floodareacalculationisbasedonseedspreadalgorithm.Theflooddamageevaluationiscalculatedbyoverlayingthefloodedarearangewiththematicmapsandrelatingtheresulttoothersocialandeconomicdata.Toraisetheoperationalefficiencyofthemodel,askippingapproachisusedtospeedseedspreadalgorithmandallthematicmapsareconvertedtorasterformatbeforeoverlayanalysis.Theaccuracyoffloodedareacalculationanddamageevaluationismainlydependentupontheresolutionandprecisionofthedigitalelevationmodel(DEM)data,upontheaccuracyofregisteringallrasterlayers,anduponthequalityofeconomicinformation.ThismodelhasbeensuccessfullyusedintheZhejiangProvinceComprehensiveWaterManagementInformationSystemdevelopedbytheauthors.TheapplicationsshowthatthismodelisespeciallyusefulformostcountiesofChinaandotherdevelopingcountries.
