Application of HEC-HMS model for simulating floods in the Ban Mong reservoir and related downstream sub-catchments

Abstract

      This study presents the simulated results of the flood flows in the Ban Mong reservoir and related downstream sub-catchments when using the HEC-HMS model. Firstly, the model parameters are carefully calibrated using the flood flow observed on 24-25/7/2015 and based on the trial and error method. The model is then validated using the flood flow measured on 26-27/7/1991, before it is applied to simulate the flood flows corresponding to the given rainfall on 4-7/8/2017. The results show that the model represents the observations of the floods very well, with r ≥ 0,93, NSE ≥ 0,80, the discrepancy between observed and simulated flood peaks is only about 5% of the observed magnitude of the flood flow at the comparison location. The time of flood flows in the Ban Mong reservoir and four related downstream sub-catchments remains of about 24 hours. In addition, the flood peak appears quite similarly to the occurrence of the rain peak at the Ban May, Ban Cuon and Son La stations.