5:15 PM - 6:45 PM
[HDS10-P09] Preliminary study on evacuation-difficult areas using network analysis of tsunami evacuation facilities assuming multiple scenarios
Keywords:tsunami evacuation, evacuation-difficult area, tsunami evacuation facility, network analysis
The 2011 off the Pacific coast of Tohoku Earthquake caused numerous casualties due to tsunami. The anticipated Nankai Trough earthquake is expected to cause significant casualties due to tsunami along the Pacific coast. The purpose of this study is to assess the potential risks of areas becoming difficult to evacuate by focusing on tsunami evacuation facilities and evacuation target points1 through network analysis.
The study area is the third district of Numazu City, Shizuoka Prefecture, Japan, where tsunami evacuation facilities are designated actively. We analyzed a total of nine scenarios with different conditions including currently assumed scenarios. Then, we assessed the areas where evacuation is possible and evacuation-difficult areas by analyzing different evacuation start times and evacuation speeds.
Preliminary results showed the evacuation-difficult areas for each scenario, and potentially high-risk areas by comparing the scenarios (see photo "network analysis result"). Specifically, the results revealed the area around the mouth of each river within the district is likely to become an evacuation-difficult area when the evacuation speed and time are delayed. The absence of tsunami evacuation facilities caused a risk of being left behind in the event of tsunami inundation in some areas. The findings of this study indicate that some district areas should be prioritized for tsunami evacuation measures, such as designating new tsunami evacuation facilities or providing disaster prevention education. Further studies are necessary to conduct risk assessment and facility location considering the capacity of facilities and the surrounding population.
1: Here, the evacuation target points are defined as the intersection points between the outer edges of the tsunami inundation area and roads.
The study area is the third district of Numazu City, Shizuoka Prefecture, Japan, where tsunami evacuation facilities are designated actively. We analyzed a total of nine scenarios with different conditions including currently assumed scenarios. Then, we assessed the areas where evacuation is possible and evacuation-difficult areas by analyzing different evacuation start times and evacuation speeds.
Preliminary results showed the evacuation-difficult areas for each scenario, and potentially high-risk areas by comparing the scenarios (see photo "network analysis result"). Specifically, the results revealed the area around the mouth of each river within the district is likely to become an evacuation-difficult area when the evacuation speed and time are delayed. The absence of tsunami evacuation facilities caused a risk of being left behind in the event of tsunami inundation in some areas. The findings of this study indicate that some district areas should be prioritized for tsunami evacuation measures, such as designating new tsunami evacuation facilities or providing disaster prevention education. Further studies are necessary to conduct risk assessment and facility location considering the capacity of facilities and the surrounding population.
1: Here, the evacuation target points are defined as the intersection points between the outer edges of the tsunami inundation area and roads.