Identification of risk hotspots to storm events in a coastal region with high morphodynamic alongshore variability

High-energy storm events induce hazards that promote damage and destruction of property and infrastructure. Defining high-risk areas is therefore fundamental to prioritise management actions. This work presents the application of an approach to identify hotspots of storm impact at a regional scale (tens to hundreds of kilometres). The Coastal Risk Assessment Framework Phase 1 (CRAF1) is a hotspot selection method based on a coastal index that combines the potential hazard (i.e. overwash and erosion), the exposure (based on land use) and the vulnerability (based on socio-economic data) along each kilometre of the coast to assess the risk level. The suitability of the approach was tested on the southeastern coast of the Gulf of Cadiz (South Spain). CRAF1 was applied considering a morphological worst-case scenario and events of 10/50/100-year return period. The region shows a high overwash and erosion hazard level. Nevertheless, a relatively low number of risk hotspots were identified due to the low level of occupation in the study area. Comparison against available information of previous overwash and erosion events proved the reliability of the method to identify hotspots at a regional scale, even in a coastal area with high alongshore variability (geomorphology, wave exposure and tidal range). The results support the utility of the tool for coastal managers to prioritise and support risk reduction plans. Furthermore, the method presents two aspects that enlarge its potential applicability: (1) it is relatively easy to apply at a regional scale, and (2) it can be updated with new data to test different scenarios (e.g. sea-level rise).