Post-Fire flood hazards as a cascading sustainability crisis: Integrated modelling, protection measures, economic assessment, and a governance roadmap through the SDG lens

Climate change is intensifying wildfires, which in turn amplify flood hazards through altered soil infiltration, increased runoff, and debris-laden flows, forming a cascading crisis threatening multiple Sustainable Development Goals (SDGs). This chapter presents an interdisciplinary framework that integrates remote-sensing burn-severity mapping and atmospheric model-based storm simulation linked to 2D hydraulic-hydrodynamic modelling to represent real post-fire flash floods. An overview of the most common post-fire erosion and flood-protection treatments (PEFTs) is then provided. A typical Mediterranean catchment is used as an application example where the models run, and the PEFTs are designed, spatially mapped, and tested within the hydraulic model, demonstrating that they can fully offset fire-induced flooding increases. Economic analysis reveals that protection costs are a fraction of direct flood damages, establishing a compelling case for proactive investment. Drawing on an established governance framework (the values-rules-knowledge approach), the chapter diagnoses institutional barriers to PEFTs implementation and proposes a stakeholder capacity-building roadmap, linking findings to SDGs 1,2,3,6,9,11,13, and 15.