Index of Proportional Risk (IRP) Flood-Risk Assessment Model and Comparison to Collected Data

After the publication of the flood directive hazard and risk maps, risk assessment and risk evaluation became useful tools to set priorities for flood management and for countermeasure financing. Regione Piemonte, in collaboration with Politecnico di Torino and University of Turin, proposed a procedure for risk assessment (named IRP model, Index of Proportional Risk), already applied in different case studies. The comparison among the obtained results and the collected data on damages recorded during the recent 2016 flood in Piemonte region showed the effectiveness of the IRP procedure for the quantitative assessment of direct damages. The IRP model can also be usefully applied to the revision and the updating of flood directive risk maps and to assess the cost/benefit ratio of the designed countermeasures (National Repository for Soil defense (Re.N.Di.S.) procedure).