FLOOD INUNDATION MODEL FOR HIGHLY URBANIZED AREA AND ITS APPLICATION TO SIMULATE THE FLOOD INUNDATION IN 2004, KOFU CITY-JAPAN

Abstract

The flood inundation model for highly urbanized area is different with general flood inundation due to the increasing of the complexity of nature and internal boundaries. As consequences, the flow is complex and requires a stable numerical model to solve it. In this paper, the flood inundation model for highly urbanized area is presented. The explicit MacCormack scheme was used to solve the flow equations. The artificial viscosity scheme was added to reduce the numerical oscillations. The model was first verified by the benchmark tests. Here, the simulated results were compared with the analytical solutions. The good performance of the model was achieved. The model was applied to simulate and to evaluate the past flood inundation in 2004, Aioi area of Kofu, Yamanashi. Compared with the observed data, the model was satisfied to be applied in highly urbanized area. It could be a useful tool for the water authority and the local government to design the countermeasures, to identify the inundation processes and to determine the potential inundation hazard map.