Performance of HEC-HMS and IHACRES Hydrological Models in Simulation of Flood Hydrograph

Simulation with using of computer models are developing very fast and these models are essential tools for understanding of man from the watershed and hydrological processes. In this study IHACRES and HEC-HMS rainfall runoff models was used for simulation of four flood hydrographs in Kasilian watershed with area 67.8 square kilometers in Mazandaran province. To prepare the Requirements maps for running HEC-HMS model was used HEC-GeoHMS extension. Hyetograph data with 15 minutes time step and its related hydrograph was entered to two models based on 1 hour time step. Then simulation of the flood hydrograph was done based on 15 minutes time step. CP and RE% statistical coefficients was used for evaluation of models performance. Values of this coefficients using the HEC-HMS model for flood 26 November 1994 was calculated 0.72 and 118.26 respectively and for flood 6 October 1996, 0.89 and -24.63 respectively and using the implementation of IHACRES model these coefficients in the first flood was calculated 0.63 and 152.4 respectively and in the second flood 0.79 and -35.6 respectively. The results showed that both use models have acceptable performance for simulation of flood hydrograph in this area and HEC-HMS model has better performance in compared with IHACRES model.