Risk-Guided Flood Segmentation from Optical Satellite Imagery Using NDWI Threshold Optimization and Segment Anything Model

This study tracks how flood susceptibility has changed across Canada over the past 24 years. By analyzing yearly flood susceptibility maps and identifying unusually wet and dry periods, the work reveals rising susceptibility in many regions, especially since 2017. The results help show where flood trends may be increasing and support long term planning and climate adaptation.

The advent of new satellite technologies improves our ability to study floods. While the depth of water at flooded buildings is generally the most important variable for flood researchers, extracting this accurately from satellite data is challenging. The software tool presented here accomplishes this, and tests show the tool is more accurate than competing tools. This achievement unlocks more detailed studies of past floods and improves our ability to plan for and mitigate disasters.