Influence of Car Evacuation on the Effective Location of a Tsunami Evacuation Shelter

The 2011 Tohoku Earthquake and Tsunami caused catastrophic damage to the coastal areas of the Tohoku Region, Japan, with elderly and disabled individuals having been suffered from significant damage. To address the issue of their reduced mobility, vehicular use for tsunami evacuation has been partially accepted in Japan. This paper aims to investigate the impact of constructing a new tsunami evacuation shelter on mortality rates, taking into account the use of vehicles by evacuees. To achieve this, the authors used an agent-based tsunami evacuation simulation model that considers the behavior of both pedestrian and car evacuees. The study applied the simulation model to Mihama Town, Wakayama Prefecture, Japan, under a future Nankai–Tonankai Earthquake Tsunami scenario. The authors first calculated mortality rates for scenarios with and without vehicular usage, using the current layout of existing refuge centers in the study area. They then investigated how mortality rates would change by placing a new shelter in the study area for both scenarios. The results showed that the effective shelter location for reducing mortality rates greatly depended on whether vehicular usage was considered or not.