The Combination of HEC-Geo-HMS, HEC-HMS and MIKE11 Software Utilize in a Two Branches River Flood Routing Modeling

The aim of this research is flood routing in a two branches river (case study ZOSHK river). We had enough observed discharge data at the upstream hydrometric station of the main branch; and also, water level-discharge data at the downstream of junction as the boundary conditions of model (for 30 years up to know); but unfortunately, there was no hydrometric station on the secondary branch. On the other hand, based on the Mass Continues Equation, if we want to have equal computed statistics to observed data at the outlet of this river, we have to model the effect of secondary and main branches together. Therefore, in this project we used HEC-Geo-HMS software to prepare required statistics for Rainfall-Runoff modeling in HEC-HMS software. Then we used Curve Number as calibration parameter to correct computed statistics with observed data at upstream hydrometric station. Later on, we used the output information of HEC-HMS model as input data for flood routing modeling in MIKE11 software. Finally, we calibrated computed statistics of MIKE11 software in compare with observed data in hydrometric station which was located in that river outlet. Consequently, we suggested a suitable procedure for flood routing in rivers which are similar to this case study with uncompleted initial and boundary conditions.