Risk analysis of mutual influence relationships among residents under rescue operations in long-term flooded areas

Abstract

Recent climate change is expected to cause severe flood damage, and new flood countermeasures are urgently required. However, there is concern that the current capacity of rescue operations is limited in response to the increasing scale of flood damage. In future flood countermeasures, it will be necessary for the government not only to carry out rescue activities but also to demand a balance between self-help and public assistance, for example, by requesting residents to evacuate voluntarily. However, to expect a change in the attitude of the residents themselves, it is important to communicate the risk by presenting evidence for such a change. Therefore, in this study, problems related to the rescue of isolated residents in water rescue operations in long-term inundated areas and the effects on residents waiting for rescue were identified. Specifically, we conducted a rescue simulation using a multiagent system in an actual urban area that was expected to be flooded for a long period. We confirmed that boat rescue operations are subject to more restrictions than ground rescue operations and pose a significant risk to residents waiting for rescue operations. We observed a strong interrelationship between residents who shared limited rescue resources, and that the decisions of individual residents influenced each other's rescue time. These relationships have given rise to an ethical problem called rescue triage owing to the nature of boat rescue operations. This study does not aim to find a rescue policy or an efficient rescue operation but discusses risk management in rescue operations in a long-flooded area.