Three large well-known hydrologic models, the Streamflow Synthesis and Reservoir Regulation, the National Weather Service River Forecast System, and the Saskatchewan River Model No. 6, were calibrated and verified on a 2000 km2 watershed in northern Ontario over two spring snowmelt periods. Although results obtained were adequate it was thought that a smaller simpler model could be designed that would give results at least as good with much less expenditure of time, money, and effort. Details of the relative performances of the three existing and one new model are given and comparative hydrographs are shown. Although use of the models on only one basin cannot provide conclusive evidence of the models' relative goodness, the results obtained do show significant differences between the models as well as certain advantages for the new model.