2015 年 21 巻 p. 265-270
Disaster possibility by mid-sized floods has not been focused much comparing to large-sized ones. In jurisdiction of Keihin River Office, mid-sized floods have caused disasters in the past. There are high possibilities that these types of disasters lead to serious disasters.
In this paper, we analyzed causes of a wide range of erosion at right bank upstream the Omaru weir by mid-sized flood brought by typhoon No.18,10.2014, which scale is 30m maximum breadth and 400m length. Moreover, we examined and proposed emergency countermeasure to mid-sized flood disasters, and the way of daily river-maintenance, considering other momentous mid-sized floods disasters occurring in jurisdiction of Keihin River Office in addition to erosion described above.