Deep aquifers are the main drinking water supply in the Bordeaux Metropolitan Area, France. However their sustainability is threatened by demographic growth and climate change. Alternative water resources, such as surface water tables, can substitute some present or future water uses that are currently covered by the drinkable water network.

Various innovative rainwater management solutions are to be evaluated in this thesis, especially Nature-Based Solutions (NBS). Indeed NBS can provide rainwater infiltration solutions, as well as address other urban issues that Bordeaux aims to tackle (urban heat island effects, biodiversity conservation, air pollutant removal, …).

The goal of this work is to perform an integrated economic valuation of the various costs and benefits associated to these solutions, depending on their spatial distribution. The economic assessment also aims at creating a decision helping tool for settling between these innovative solutions, and plan their location. The thesis will aim at creating a spatially explicit valuation method, and will mobilize various economics methods : multi-objective optimization, cost-benefit analysis, multi-criteria decision analysis, contingent valuation, choice experiments.

Key words : Environmental economics, ecosystem services, Nature-based solutions, multi-criteria decision analysis

Nature-Based Solutions generate multiple benefits for cities Source: Rhine Meuse Water Agency