Assessment of flood risk reflecting regional characteristics of urbanization in South Korea

Abstract

In recent decades, extreme weather events including heavy rainfall and flash floods have increased all over the world. For reducing the likelihood of flood events and making a resilient society, it has become important to understand the interaction of flood occurrences and regional characteristics because damage can vary depending on the spatial and temporal variation. In this study, we examine the interaction of flood risk and regional characteristics on the temporal and spatial (urban and rural) context by analyzing flood property losses in Korea from 2000-2014. Specifically, the study period is divided into three parts with five-year intervals in an effort to better understand how to change the influence of the hazard, topography, land-use, capacity, and socioeconomic factors as well as urbanization on property damage over time. The findings suggest that 1) some variable are continuously significant to flood property damage during 15 years, 2) there is a change of effects on flood property damage not only significance but direction in some variables over time, and 3) geographic localities characterized by the degree of an area’s urbanization have a different pattern of flood risk in terms of land use and socioeconomic factors. In particular, heavy downpours that occur in a short time can generate much bigger damages than precipitation which accumulates over a longer time. And mountainous areas contain a lot of steep slope-land are more vulnerable to flood risk than floodplain area, but the land use characteristics of floodplain area is important to assess the flood risk. Empty houses variable is only significantly associated with flood damages in rural area. This study provided the evidence that the trends and changes of flood risk during the last 15 years by examining significant factors which associated with flood property losses on the temporal and spatial (urban and rural) approach. In this regard, the findings are expected to help urban planners and disaster managers to develop regionally appropriate methods for flood damage reduction.