Integrated Flood Risk Analysis in Tosya Using Gumbel Distribution QGIS and HEC-RAS Simulations (Kastamonu, Türkiye)

This study presents a comprehensive flood risk assessment for Tosya, Kastamonu, Türkiye, integrating statistical, geospatial, and hydraulic modeling techniques. Extreme rainfall events were analyzed using the Gumbel distribution to estimate return periods and probable maximum precipitation, providing a quantitative basis for understanding flood hazards. High-resolution Digital Elevation Model (DEM) data were combined with QGIS to delineate flood-prone areas and visualize flood hazard zones, while HEC-RAS simulations modeled water flow dynamics under varying precipitation scenarios. The integrated approach identifies high-risk areas, offering a scientific foundation for flood management, early warning systems, and urban planning. As the first academic study on flood risk in Tosya, the findings fill a critical knowledge gap and provide a reference framework for future research. The study demonstrates that combining statistical analysis, spatial modeling, and hydraulic simulations enhances flood risk prediction and supports effective disaster preparedness in the region.