2016 Volume 22 Pages 31-36
The Kanda River which flows through densely urbanized area has many flood-control facilities and sewerage systems. But sufficient understanding is not made how heavy rainfall waters move in the basin and flood-control facilities work during floods. However, it is difficult to observe moving waters of heavy rainfalls. In this paper, we conducted the two- dimensional analysis of flood flow using time series of observed water surface profiles in the Kanda River. As a result, the calculation model for 2013 flood provided good evaluation of inflow discharge hydrographs from sewerages and flood storage volume in the Loop Road No.7 Underground Regulating Reservoir and Wada Yayoi Trunk Sewer. It is found that flood storage volumes of sewer facilities depend on river water levels during a flood. To design a comprehensive drainage plan for urbanized areas, movement mechanism of heavy rainfall waters in drainage areas and appropriate integration of both river and sewers systems must be conducted.
