Modelling of streamflow in snow dominated Budhigandaki catchment in Nepal

This study has been envisaged to model streamflow runoff-contributed mostly by snowmelt from Budhigandaki catchment in Nepal. Available hydro-meteorological data have been collected from the Department of Hydrology and Metrology, Nepal. The MODIS Aqua (MYD10A2) and Terra (MOD10A2) 8 day maximum snow cover extent product have been used to derive the snow cover area (SCA) in the basin. The modeling of streamflow has been carried out using HEC-HMS and SRM models. The performance of these models have been evaluated by using three well known evaluation criteria NSE, \({R}^{2}\) and PEV (percentage error in volume). The values of NSE, \({R}^{2}\) and PEV were found to be 0.944, 0.944 and \(-0.3\%\) for SRM and 0.778, 0.785 and \(-1.83\%\) for HEC-HMS, respectively. Similarly, in validation period the average values of NSE, \({R}^{2}\) and PEV were found to be 0.811, 0.816 and 2.01% for SRM model and 0.773, 0.777 and 3.5% for HEC-HMS, respectively. Sensitivity analysis of the models revealed that constant loss rate is very sensitive parameters for HEC-HMS model, whereas runoff coefficient is found to be most sensitive parameters for SRM model. In comparison between two models SRM model has given slightly better simulation results compared to HEC-HMS model.