ScsHyd is essentially the same as the NasHyd with the exception that it uses parameters for the SCS Procedure (i.e. initial abstraction is a function of the SCS Curve Number, and the number of linear reservoir “N” is set to 5). This command can be used when the SCS procedure is required by agencies or for comparison with other options.


Parameter Name Description Default Value
CN SCS Modified Curve Number. The initial abstraction is calculated as 0.2 × S, and S is a function of Curve Number. 80
TP Unit Hydrograph time to peak (hr). It is approximately equal to (N-1)/N × TC where TC is the Time of Concentration. DT should be smaller than TP. 0.2