Flood risk assessment in support of the evaluation and selection of risk mitigation measures

The purpose of the study is to define how the models available for flood damage assessment in the Italian context can support cost-benefit or multi-criteria analyses of risk mitigation measures, in accordance with current laws and regulations on the subject. On the basis of the present situation in which risk mitigation measures are evaluated mostly according to their capability of reducing the hazard and by considering few simple exposure factors, the study aims at identifying more robust indicators to assess measures effectiveness based on results from flood damage modelling. State of the art flood damage models developed within the context of the project MOVIDA (MOdello per la Valutazione Integrata del Danno Alluvionale – Model for integrated evaluation of flood damage, https://sites.google.com/view/movida-project) were applied to evaluate the expected damage in several flood prone areas within the Lombardia Region (northern Italy), where mitigation actions are planned by the Regional Authority. Then, obtained results for these areas were analysed to define effectiveness indicators as well as their range of values. Finally, specific indicators were developed to evaluate the environmental impact of each intervention according to present policies to promote sustainable investments in the field of soil protection as well as contribute to achieve Green Deal goals. Results show that developed indicators increase the ability of local authorities in the definition of priorities of intervention, leading to a reduction of institutional and legislative inefficiencies and increasing the efficiency of disaster risk reduction policies.