Abstract
We need to establish more effective evacuation measures for combined inundation by
simultaneous multiple inflow of sediment and flood in densely populated areas close to
mountainous terrain and rivers. In this study, using the numerical model considering combined
inundation by simultaneous multiple inflow, we investigate the safeties of evacuation passes to
several refuge sites during the combined inundation. The safeties are based on a simple
relationship about the required time to move from “evacuation starting points” to “refuge sites” and the difference time of inundation starting between these two points. As a result, since we
estimated the distribution of potential for suffering flood damage during the combined inundation,
we could identify the more safety evacuation passes and refuge sites. In addition, our
investigations could be estimated the magnitude of the influence by each flooding factor on the
combined inundation.
