Estimation of flood damage using building group inventory and multidimensional flood damage analysis

Abstract

As a result of the recent climate change, damage caused by local floods and typhoons has frequently occurred, and many lives and properties have been affected in the process. In particular, in the city center, much damage is set to occur because of river inundation. In this study, the flood damage area was calculated using the FLO-2D model, which is a flood inundation model, and the estimated flood damage amount was calculated by using a multidimensional flood damage analysis (MD-FDA). Through the FLO-2D model, flood damage area was calculated by flood inundation simulation by frequency (50, 80, 100, and 200 years). The flood damage rate for land use (residential, agricultural, and industrial) was calculated by overlapping flood damage area calculated using a geographic information system (GIS), a Wonju land use map, and an administrative district map. The flood damage rate is calculated using the area ratio according to the land use in the administrative district. However, in this study, flood damage rate is calculated using the flood damage rate proposed in the multidimensional flood damage analysis. Estimated flood damages by frequency were estimated using an estimated flood damage rate. In addition, the total damage amount was calculated by applying the damage rate of public facilities presented by the Ministry of National Land Construction of Japan. The results indicate that the flood damages estimated using area ratios were lower by up to 96% than those using building groups, and lower by 57% on average when the public facility damage rates were applied. Therefore, for analysis of flood damage using MD-FDA, building group-based damage estimation is recommended for residential and industrial areas.