Cost-benefit analysis of flood prevention. Application of the damage avoided approach in the Orb catchment

Abstract

This article explores the relevance of implementing a Cost-Benefit Analysis (CBA) of flood prevention policies via the Damage Avoided approach. Based on a case study in the Orb catchment (Hérault), the article reminds the different steps of the approach, in particular the modelization of assets in floodplains and the calculus of mean annual damages. The article proposes different ways to present the results : the net present value, a map of potential damage and a map of expected benefits, and shows how these results can contribute to the definition of flood management strategies, for example by the choice of design-floods. The discussion deals with the transferability of the method, its limits and perspectives for further developments.