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

Abstract

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).

A Preliminary Contribution towards a Risk-Based Model for Flood Management Planning Using BIM: A Case Study of Lisbon

“…The EFD aims “to reduce the risk of adverse consequences from flooding, especially for human health and life, the environment, cultural heritage, and economic activity”. However, according to articles 5 and 6, the EFD mandates mapping only for those zones exposed to risk or possibly exposed to risk and does not require a quantitative risk estimation [ 26 ]. The type of analysis, the scale of representation and the tool to use for risk assessment, as well as risk modelling, are not specified in the EDF.…”

“…According to the European commission document titled, “Floods Directive Reporting Schemas” [ 25 ], the methods for reporting are different, and quantitative estimation is optional. The description of the risk and its factors can be indicated as a range, as a percentage of the total GDP for the flood event, by classes (Insignificant, Low, Medium, High, Very High), or by means of other numerical measure indicative of the degree of potential adverse consequences, leaving a wide choice for implementation [ 26 ]. We grouped buildings by classes and assigned values from 1 to 5 (1 low, 5 high) for each analysed risk element.…”

A complete methodology to assess hydraulic risk in small ungauged catchments based on HEC-RAS 2D Rain-On-Grid simulations

“…The Index of Proportional Risk (IRP) method (Franzi et al 2018) was employed for risk assessment and quantification in this study. The IRP model has been successfully used in various case studies within Piedmont (Franzi et al 2016(Franzi et al , 2018 demonstrating its effectiveness in estimating flood risk for the present context.…”

“…The Index of Proportional Risk (IRP) method (Franzi et al 2018) was employed for risk assessment and quantification in this study. The IRP model has been successfully used in various case studies within Piedmont (Franzi et al 2016(Franzi et al , 2018 demonstrating its effectiveness in estimating flood risk for the present context. The IRP model calculates an "index" that is based on a scientific approach to risk and damage estimation, considering available regional and national databases.…”