Previousstudiesathomeandabroadhavemainlyfocusedonsingledam-break,andlittleattentionhasbeenpaidsofartothedam-breakofcascadereservoirs.Multi-sourceflooding,whichcanleadtothree-dimensionalturbulentphenomenaandsuperpositioneffects,isthemaindifferencebetweenthedam-breakofcascadeandsinglereservoirs.Detaileddescriptionsofthecouplednumericalsimulationofmulti-sourcefloodinghavelittlebeenreported,andtheinitialwetriverbedisrarelyconsideredincurrentmodels.Therefore,inthispaper,amethodbasedonthethree-dimensionalk_eturbulencemodelcoupledwiththevolume-of-fluidmethodisproposedtosimulatethedam-breakfloodingofcascadereservoirs.Theupstreamriver,reservoir,anddownstreamriverareconnectedbytheinternalboundarymethod,andtheinitialconditions,includingriverflowandreservoirwater,aredeterminedaccordingtotheresultsofthenumericalsimulation.Couplednumericalsimulationofdifferentdam-breakfloodingisthenachieved.Thepresentworksolvesthechallengespresentedbytheenhancementandsuperpositionofnaturalriverflow,upstreamflooding,anddownstreamflooding.Thispaperprovidesatheoreticalbasisforfuturestudiesonthedam-breakfloodroutingofcascadereservoirs.