Non-structural measures for flood risk mitigation are often more economically accessible, easier to implement, and are highly effective, especially in view of the pursuit of risk resilience objectives. Among the non-structural measures, more importance is increasingly being attributed to flood proofing interventions. There are two main types of flood proofing: dry proofing and wet proofing. An example of dry proofing is shielding, which involves the use of flood barriers that can be installed in the entrances of buildings or outside the buildings in order to avoid contact with the houses and deviate the water flow. Their use must be supported by a detailed hydraulic analysis to ensure the correct design is used. This kind of intervention also avoids inducing a feeling of false security (the levee effect) in the exposed population, and therefore contributes to increasing their resilience. The aim of the work presented here is to determine an optimal combination of and choice between different types of structural and non-structural measures through the development of a methodology for assessing the real efficiency levels of different measures, using a cost–benefit analysis (CBA) and starting from the estimation of the direct flood damage. The application of the CBA to a case study of the Mela river in northeastern Sicily, which suffered a flooding event in October 2015, is supported by the determination of the real damages after the flood and the modeling of the same damages for alternative scenarios. The results affirm the possibility of reducing or avoiding some of the damage using the proposed flood proofing measures instead of classical ones.

<div> <div> <div> <p><strong>Flood proofing measures cost-efficiency analysis for hydraulic risk mitigation in an urbanized riverine area</strong></p> <p>Ugo Ventimiglia <sup>2</sup>, Angela Candela <sup>1,</sup> Giuseppe Tito Aronica <sup>2</sup></p> <p><sup>1 </sup>Department of Engineering, University of Palermo, Palermo, Italy</p> <p><sup>2 </sup>Department of Engineering, University of Messina, Messina, Italy</p> <p>Use of non-structural measures for flood risk mitigation is often more economically accessible, easy to implement and are highly effective, but only if this use is supported by a detailed hydraulic analysis necessary for a correct design. Among the non-structural measures, a progressive and increasingly accentuated importance is attributed to flood proofing interventions, especially in view of the pursuit of risk resilience objectives. Flood proofing interventions are normally classified in two main types: dry flood proofing and wet flood proofing. One measure of dry flood proofing is the shielding, which consists in the use of flood barriers, which can be installed at the entrance of the buildings or at a certain distance from them in order to avoid contact with the houses and deviate the flow of water. A similar type of interventions also avoids inducing sensations of false security (levee effect) in the exposed population and therefore contributes to increasing their resilience. In the context of risk management, resilience is the intrinsic ability of a system to modify its functioning before, during and following a change or an event, so as to be able to continue the necessary operations both under expected conditions and under unexpected conditions. Aim of work presented here is to determine an optimal combination and choice between different types of structural and non-structural measures, through the development of a methodology for assessing the real effectiveness of different measures, through a cost-benefit analysis (CBA) starting from the estimate of direct flood damage. The application of the CBA, to the real case study of the Mela river, located in north-eastern Sicily, which suffered a flooding in October 2015, supported by the determination of the real damages after the flood and the modelling of the same for the alternative scenario, has returned results significant capable of affirming the ability to reduce or avoid part of the damage.</p> <p>https://drive.google.com/file/d/14dlP9Nt0A8bc4UUrv8az8pxIHp8bZ6GV/view?usp=sharing</p> <p> </p> </div> </div> </div>