Small basin flash flood simulation with TOPMODEL

The semi-distributed physically-based hydrologic model has the advantage of a simple model structure and lesser model parameters together with a realistic representation of the basin hydrologic process. This paper investigated the effectiveness of small basin flash flood simulation employing TOPMODEL, a semi-distributed physically-based hydrologic model first proposed by Beven and Kirkby. Floods in the Fanjingtang basin, a small basin in southern China with mountainous topography in the upper area and flat topography in the lower area, were simulated with TOPMODEL. The results were compared with those simulated by the Xinanjiang model, with which the parameters were calibrated by using the same observed data. It shows that the results simulated by TOPMODEL are reasonable and have a better simulation of the peak discharge of the flood than those simulated by the Xinanjiang model. The conclusion is that TOPMODEL is a simpler hydrologic model with a realistic representation of the basin hydrologic process, which can be used for the flash flood simulation of the Fanjingtang basin.