A comparitive study on the different rainfall-runoff models

Accurate prediction of rainfall-induced runoff process is important for design, management and planning of drainage systems in a catchment. Conceptual Rainfall-Runoff (CRR) models have been frequently used in order to simulate the rainfall-runoff process with physical parameters. These models estimate the response of a watershed by using physical and hydrological parameters of a catchment based on different mathematical models. In this study, five independent events, which were observed from storm data for the period between 1990 and 1995 in Cascina Scala catchment (Pavia, Italy), were simulated by HEC-HMS, and EPA-SWMM models. This comprehensive study was performed in order to evaluate the comparative performance of these models. The estimated rainfall-induced runoff, and peak discharge were compared with the corresponding observed values. The comparison was performed by considering the root mean squared error (RMSE) and the coefficient of efficiency (CE) between the observed event data and estimation results. The results showed that EPA-SWMM model outperformed the HEC-HMS model in estimating total runoff. The performance of HEC-HMS model in estimating the peak discharge was found to be better than EPA-SWMM model.

Keywords:

hydrograph , HEC-HMS , EPA-SWMM , rainfall-runoff model , hydrology