Author(s): Yuko Ishida; Yoshiya Ogawa

Linked Author(s):

Keywords: Retarding basin; Flood control; Green infrastructure; River basin disaster resilience and sustainability

Abstract: The Ogura-Ike Pond (area of 794 ha and maximum water depth of 1.1 m), located in the middle basin of the Yodo River Basin, possessed a flood control function because of being connected to the Uji River through a braided channel and inhabited various organisms of the Yodo River Basin. After being diked in 1941, the pond lost its flood control function and living things disappeared from it. Recently, heavy rainfall has been occurring more frequently than expected in various areas in Japan. The Ministry of Land, Infrastructure, Transport and Tourism has announced a new policy, River Basin Disaster Resilience and Sustainability by All, that considers river basins as spaces that include the watershed and flood plain areas (Ministry of Land, Infrastructure, Transport and Tourism in River basin disaster resilience and sustainability by all—Japan’s new policy on water-related disaster risk reduction, 2020). Flood disaster risks are also increasing in the middle and downstream basin of the Yodo River Basin. In this study, we considered that whether the water level and flow rate in the middle and lower reaches of the Yodo River could be reduced by installing a retarding basin in the middle reaches of the Yodo River Basin, using unequal flow analyses and unsteady flow analyses. These results of analyses showed that the water level could be reduced by 0.2 m and the flow rate could be reduced by 500 m3/s at the downstream Hirakata point by installing a retarding basin.

DOI: https://doi.org/10.1007/978-981-97-6009-1_6

Year: 2022