EVALUATION OF MAKESHIFT FLOOD PROTECTION WALLS FOR INUNDATION CONTROL IN RAPID STREAM BASIN

Abstract

 Under the global warming condition, it is indispensable to consider flood control measures on the premise of the huge inundation along with bank overtopping or levee breach caused by major floods. In this study, for the Tedori River Basin which is one of leading torrential rivers in Japan, inundation simulations were conducted under the conditions of the assumed maximum rainfall and the rainfall (L1.5 rainfall) between the assumed maximum and the design level to evaluate flood control ability of makeshift flood protection walls installed on existing roads. In both the assumed maximum rainfall and the L1.5 rainfall, the changes in the maximum inundation depth were slight in all three installation patterns of the makeshift flood protection walls. It was clarified that the Tedori River Basin has a steep topographical gradient, so the inundation flow is fast and the facility is difficult to be effective, and the flood control facility has very small water storage capacity.