Reporting flood damages: a model for consistent, complete and multi-purpose scenarios

Abstract. Effective flood risk mitigation requires that the impacts of flood events would be much better and more reliably known than is currently the case. Available post flood damage assessments usually supply only a partial vision of the consequences of the floods as they typically respond to the specific needs of a particular stakeholder. Coherently, they generally focus (i) on particular items at risk, (ii) on a certain time window after the occurrence of the flood, (iii) on a specific scale of analysis or (iv) on the analysis of damage only without an investigation of damage mechanisms and root causes. This paper responds to the necessity of a more integrated interpretation of flood events as the base to address the variety of needs arising after a disaster. In particular, a model is supplied to develop multi-purposes complete event scenarios. The model organizes available information in the post event according to five logical axes. This way, post-flood damage assessments can be developed that (i) are multisectoral, (ii) address the spatial scales that are relevant for the event at stake depending on the type of damage, i.e. direct, functional, systemic, that has to be analyzed, (iii) consider the temporal evolution of damage, and finally (iv) allow to understand damage mechanisms and root causes. All the above features are key for the multi-usability of resulting flood scenarios. The model allows, on the one hand, the rationalization of efforts currently implemented in ex-post damage assessments. On the other hand, integrated interpretations of flood events are fundamental to tailor and optimize flood mitigation strategies, as corroborated by the implementation of the model in a case study.