5.5 WILLIAMS IUH - Visual OTTHYMO

The method is recommended for rural watersheds where observations indicate a long hydrograph recession limb. The Williams formula for Tp is not recommended in Ontario as it has been shown to give significant errors.

WILLIAMS IUH

As is predecessor (INTERHYMO / OTTHYMO.89), Visual OTTHYMO does not recommend default values for K and Tp in the Williams command, since it is considered that this IUH requires calibration.

COMPARISON OF WILLIAMS AND NASH IUH

5.4 SCS IUH (SCSHYD)

5.6 Use of IUH’s for I/I Simulation and Baseflow (DWF)