Research on flood risk assessment based on rainfall, river flow rate, and land use

Tsurumi River as an example

Abstract

In this study, we analyzed watershed flood control in the Tsurumi River basin. The target area of the study was the Tsurumi River basin, which flows through three cities: Yokohama City, Kawasaki City, and Machida City. The study period was three days, July 1st, 2nd, and 3rd, 2021, when heavy rain occurred. Four types of data were used: watershed-related data, rainfall data, land use data, and vacant house data. The runoff amount was calculated from the analytical rainfall data. A countermeasure scenario was created based on the calculated leakage amount. To summarize the results obtained this time, the first is that the Tsurumi River basin is an area with many areas of urban land use, and the second is that the areas of urban land use in the Tsurumi River basin are replaced by natural land uses. In the scenario where the location was replaced, the amount of runoff could be reduced little by little, albeit in stages