ESTIMATION OF EVACUEES IN A SEVERE FLOOD BY CONSIDERING DIFFERENT POPULATION DISTRIBUTION AND FUTURE DEPOPULATION

Abstract

 In the Kakehashi River Basin in Ishikawa Prefecture, inundation simulations were conducted by using rainfall data under the global warming condition. After identifying the areas requiring evacuation based on the inundation simulations, the number of evacuees to each evacuation center was calculated in consideration of the difference in population distribution by time and period. The number of evacuees increases more than 2000 in areas where the population increases during the day. During summer vacation, total number of evacuees can increase. Not only the number of residents, but also the number of visitors during daytime has to be considered to make evacuation plan. In addition, number of evacuees were calculated under urban structural changes assuming relocation from areas with higher flood risk to lower risk areas in the condition of future population decline. Under the declining population, it was possible that the number of people requiring evacuation could decrease 1000 in significantly. To take advantage of surplus area to reduce the risk, it is valuable to take measures to relocate people from higher risk to lower risk areas.