2024 Volume 80 Issue 16 Article ID: 23-16069
In this study, the effect of reducing peak flows and inundation areas of tributary rivers was evaluated by simulation when storage, infiltration, and inundation flow control measures were implemented in the catchment area of Hitoyoshi city. The introduction of a rice field dam covering 1.4% of the target watershed area, storage within a school ground and park encompassing 0.04% of the target watershed area reduced peak flows in the Yamada, Nishikawauchi, and Omizo Rivers by approximately 1-8% for rainfall events with up to 50-year probability. Moreover, 1.1km long road raising within the Fuku River basin contributed to reducing approximately 51% in peak flow for this river. The introduction of rice paddy dams was estimated to decrease the inundation area during rainfall events with up to 30-year probability. Additionally, rice field dams combined with strategies involving storage within school grounds and parks and road raising reduce the flooded area for rainfall events with up to 50-year probability.
