A probabilistic approach for the socioeconomic assessment of urban river rehabilitation projects

Urban river rehabilitation aims to enhance the ecological status of urban watercourses and promote measures for the local population to increase their well-being by making a direct or indirect use of the services these ecosystems may provide. The social and economic feasibility is evaluated by contrasting the resources used in the rehabilitation process with the benefits derived from it through the Cost-Benefit Analysis (CBA). By means of a case study, this work not only introduces the most innovative CBA approaches in environmental projects, but also implements probabilistic simulation methods in order to increase the robustness of the assessment indicators.The case study encompasses two projects, whose global costs total €46 M in 50 years, for the environmental rehabilitation of the stretch of the River Segura that flows through the city of Murcia. The benefits have been obtained by a contingent valuation exercise: €3.3 M/year (€0.6 M/year of use benefits, and €2.7 M/year of non-use benefits). Three different CBA approaches (economic, extended and dual) are applied to contrast these costs and benefits, conducting the analyses of uncertainty and sensitivity of the benefit items through a Monte Carlo simulation. The results highlight the importance of environmental benefits for this kind of projects to be socioeconomically feasible thanks to the profitability indicators they provide.