Improvised Flotation “Uitemate” as a Last Resort: Lessons Learned from Elderly Survivors and Victims of the 2018 Japanese Flood Disaster

Summary: The 2018 Western Japan floods resulted in numerous fatalities among elderly residents, with many cases of “drowning at home” reported. This study analyzes victim characteristics to explore mitigation strategies for a society experiencing increasing climate-related disasters. We collected cases of home drowning fatalities during the floods in Ehime and Okayama Prefectures through media reports (newspapers and television) and analyzed survival patterns. In Ehime Prefecture, 9 (29.1%) of 32 victims drowned, with 3 (9.7%) drowning at home. All three were over 70 and found on the first floor. In Okayama’s Mabi town, 43 (84.3%) of 51 drowning victims died at home, with 36 (70.6%) being elderly (65+). 42 died on the first floor, one on the second floor. Both prefectures reported cases where surviving elderly residents reached the second floor but failed to convince their spouses to follow, resulting in spouse fatalities. In one case, an elderly couple survived by floating on their bed, which rose with the water level near the ceiling. In Ehime, a family successfully rescued a one-year-old girl and her great-grandmother using a two-seater sofa as flotation. Swimming while clothed is challenging, particularly for elderly individuals with reduced physical strength. Given that most elderly victims drowned on the first floor, the survival probability could increase through flotation strategies. When external evacuation risks are high during indoor flooding, back float and improvised flotation devices (life jackets, coolers, sealed backpacks with clothing) may contribute to survival. This survival technique, internationally known as “Uitemate” (Float and Wait), effectively prevents drowning in various flood disasters and represents a household-level disaster risk reduction strategy.