Which Mode Will Be Effective in a Massive Evacuation?

The earthquake which struck Eastern Japan in 2011 caused many casualties. The ratio of the mode of evacuation in areas damaged by the earthquake varied depending on geographical conditions, but cars were the primary mode in many areas. Although the Japanese government has provided guidelines to assist evacuation during a natural disaster, the disaster in 2011 demonstrated that the behavior of refugees did not adhere to these guidelines. This study analyzes refugees’ behavior during evacuations using a dataset gathered through surveys of refugees in 2011. By analyzing their evacuation speed and distance based on their geographical conditions, the necessary distance and available distance for their evacuation are calculated in this study, following which an optimized distance for evacuation is derived. Analyzing various modes of evacuation, such as walking, bicycling, and car travel, this study identifies thresholds for an efficient mode of evacuation based on evacuation distance. In conclusion, this study finds that a walking-based evacuation plan is necessary in most areas, whereas vehicles are required in areas where it is impossible to evacuate by walking.