Mapping Flash Flood Hazards in Arid Regions Using CubeSats

Flash flooding affects a growing number of people and causes billions dollars in losses each year with the impact often falling disproportionally on underdeveloped regions. To inform post-flood mitigation efforts, it is crucial to determine flash extents, especially for extreme events. Unfortunately, flood hazard mapping has been limited by lack observations both high spatial temporal resolution. The CubeSat constellation operated Planet Labs can fill this key gap Earth providing 3 m near-daily multispectral imagery at global scale. In study, we demonstrate imaging capabilities CubeSats hazards arid We selected severe storm 13–14 August 2021 that swept through town Gila Bend, Arizona, causing damages, two deaths, Declaration State Emergency. found extent be mapped from comparisons near-infrared surface reflectance prior after event (?NIR). unprecedented spatiotemporal resolution allowed detection ponded (?NIR ? ?0.05) flood-affected ? +0.02) areas compared remarkably well 100-year obtained an independent hydraulic modeling study. Our findings provides valuable details support activities such as damage assessments emergency relief.