Members of the EcoC2S team at the University of Granada (UGR), together with researchers of the Universitat Politècnica de Catalunya (UPC), have developed a method to detect and classify areas at high risk of compound flooding—flooding caused by the combined effects of heavy rainfall, river overflow, and coastal events such as storms and waves.
While the EU Floods Directive provides a common framework for flood risk management, current assessments often focus on single-source events, overlooking the combined risks of compound flooding. The new method efficiently identifies Areas of Potential Significant Flood Risk (APSFR) by considering the intensity, likelihood, and interactions of multiple hazards. Analyzing 1,600 km of the Spanish Mediterranean coastline, the study identified three particularly vulnerable regions: central Valencia, northern Catalonia, and western Andalusia. Of the 214 APSFRs assessed, 11% fall into the highest risk category.
Classification of the Spanish Mediterranean coast based on compound flood potential, with the three highest-risk areas outlined in black
This method stands out for its technical precision and practical applicability. Its scalable design makes it ideal for integration into the third cycle of the EU Floods Directive planning, supporting authorities in making informed decisions and improving protection against increasingly complex natural disasters.
Del-Rosal-Salido, J., Bermúdez, M., Ortega-Sánchez, M. et al. A composite index framework for compound flood risk assessment. Communications Earth & Environment 6, 342 (2025). https://doi.org/10.1038/s43247-025-02331-z