Analysis of the Risk Management Strategy for Future Flood-Related Property Damage Due to Climate Change

Abstract

In this study, we analyzed countermeasure strategies such as the pump system capacity, detention basin storage capacity, drainage system supply capacity, and river restoration ratio to cope with the flood damage increase due to climate change. To establish countermeasure strategies against future property damage from flooding, we collected 19 GCM outputs, extreme hydrological characteristic data, basin characteristic data, and several observation data including four countermeasures for 113 mid-size basins. The relationships between the property damage by flooding other variables were analyzed using a constrained multiple linear regression model. The future property damage was estimated to be the largest in the Namhangang river basin and the Yangyang Namdaecheon basin and was larger in the RCP 8.5 scenario than in the RCP 4.5 scenario. To prepare for this, when the four countermeasures were improved within the available room, the magnitude of the property damage was reduced to below the average or current property damage. However, there were limitations in the cost and manpower of improving all the countermeasures. For this purpose, it is necessary to establish an optimal plan by using multi-criteria decision-making methods.