Focusing on small- to medium-scale floods, whose frequency is projected to increase, this study examined post-disaster population dynamics and the life recovery process of affected individuals. Analysis of mobile spatial statistics for the July 2023 Akita heavy rain showed a population decline within inundated areas and spatial variation in population changes across those areas. A questionnaire survey found that preparedness measures increased after the disaster. The results show that, although physical recovery progresses quickly in small- to medium-scale floods, the restoration of local economic activity and residents’ perceptions (the “soft” aspects) takes as long as in earthquakes or large-scale floods.

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