Development of a Risk Assessment Model of Rainfall for Small Area in Declining Urban Areas

Abstract

Purpose: Declining cities are vulnerable due to their aging populations and decreasing economic activity. The risk assessment framework developed by IPCC is a representative method of analyzing hazardous impacts in urban spaces. However, most previous research on declining cities and risk assessments are based on macro-scale evaluations. As risk assessment must be included in the urban planning process, development of a risk assessment model for smaller areas is necessary. Thus, this study aims to develop a rainfall disaster risk assessment model for a small area in a declining city. Method: This study selected the appropriate indicators for a small area based on the IPCC disaster risk assessment framework. As suggested by IPCC, multidimensional data are used as indicators of the physical, social, and climate-related health of a city. The indicators include not only computational data based on GIS but practical data obtained through a field study involving a site-specific evaluation. In the developed model, the risk of a rainfall disaster at the study site is quantified with a numerical score. Result: The numerated assessment result is allocated into the grid of the case study site in Daegu, South Korea. The rasterized image visually represents the risk impact score of a rainfall disaster in a small area. Consequently, this study proposes a high-resolution risk impact assessment model that can be applied to urban design and provides the results of realistic and practical rainfall disaster analysis.