Hydrological modeling for simulation of rainfall-runoff process in mountainous catchments

The Hydrologic Modeling System HEC-HMS is designed to simulate the precipitation-runoff processes for watershed systems. It is designed to be used in a wide range of geographic areas to solve various problems. This includes large river basin, water supply, and flood hydrology, and small urban or natural watershed runoff. In this study, HEC-HMS model was applied to develop the rainfall-runoff model applications in TaghsimAb, DareMuradbeig, and Tooijin catchments in Hamedan, Iran. The model also incorporates ARC-GIS extensions, HEC-GeoHMS, and ARC-Hydro tools for the spatial analysis of the watershed. The hydrological model results showed a proper fit between simulated, and observation hydrograph shape. Clark unit hydrograph, SCS unit hydrograph, and Snyder unit hydrograph methods are used in the HEC-HMS model. Nash-Sutcliffe of the model was selected to compare, and determine the efficiency of these three methods. As a result, the Snyder unit hydrograph method is appropriate than two other methods for hydrological modeling for the present study area.