DISTRIBUTED HYDROLOGIC MODEL FOR FLOOD INUNDATION SIMULATION

摘要

There were several research studies carried out in the last few years to develop mathematical models for flood inundation simulation. However, such models considered only overland and river flows components of hydrologic cycle and were designed to simulate floods in local scale only, not in basin scale. In real situation, infiltration and base flow to river have significant impacts on the occurrence or non-occurrence of floods due to a particular rainfall event. Therefore, flows in unsaturated and saturated zones too should be considered for proper flood inundation simulation. In this study, a physically based distributed hydrologic model is developed for flood inundation simulation by combining a newly developed overland flow and river flow simulation models with unsaturated zone and groundwater models. The overland flow and river flow models are validated individually with test data and then, coupled with other models. The model is applied in a river catchment in Japan to simulate a flood event of 1996. Output of the model shows satisfactory agreement with surveyed flood inundation and thus, shows that the model is suitable for basin scale flood inundation simulation.