CHARACTERISTICS OF TEMPORAL VARIATION OF INUNDATION DEPTH DUE TO RAINWATER FLOODING IN URBAN AREAS AND RISK ASSESSMENT

Abstract

 In recent years, the frequency and amount of heavy rainfall have increased, and the risk of rainwater (internal) inundation has been increasing in urban areas where are less infiltrated areas. In this study, a rainwater inundation simulation was conducted for the eastern part of the urban area in Takamatsu City, Kagawa, Japan, by considering sewerage, drainage pumps and buildings. The results showed that the inundation depth and the flow velocity increased when buildings were considered. In addition, the results also showed that the condition, which was not taking buildings into account, underestimates the risk. It was suggested that the risk of rainwater inundation could be predicted in advance by checking the fullness of sewage pipes.