Theresultsofmathematicalmodellingofunsteadyflowconditionscoupledwithspecificsedimenttransportrelationsarepresentedhere.SimultaneoussolutionsofthedeSaintVenantequationswiththreedifferenttransportrelations,namelytheEngelund-Hansenequation,Grafequation,andanempiricalequationarepresented.TheresultsobtainedwerecomparedwiththosefromtheFluvial-12programunderthesameinputconditionsandreasonablecorrelationwasobserved.Theadvantagesofthecoupledmethodforsimultaneoussolutionoftheequationscompriseahigherdegreeofaccuracy,thepossibilityofintroductionofanydesiredtransportequationintothemodelandthepossibilityofintroducinganyboundaryconditionsintothemodelalongsideacompleteunsteadyflowmodelling.
