| Under the climate change conditions, extreme floods occur more frequently and leading to increased risks of flooding. Therefore, there is a need to model flood inundation due to levee break accurately. Information obtained from that kind of model will be useful for developing emergency measures. This study investigates the inundation process in the northeast region of the Tokyo metropolitan with assumption of levee break at right side of Tone River under extreme condition similar in size to the Kathleen typhoon on September 16th 1947, which caused the most catastrophic flood in history to the area. About 340 m length of embankment was broken at Kurihashi, in the middle reach of the Tone River (Fig. 1). The resultant floodwater rapidly expanded of about 60 km downstream to the Tokyo metropolitan within only two days, killed more than 1,000 people and caused great damage in the Kanto area. The purpose of the study is to use the model to simulate and then investigate flood inundation processes under the present topography and land uses conditions with extreme inflow flood discharges caused by climate change for mega-urban areas likes Tokyo. |
