CBA § Darwin: The Case of Transport Infrastructure in France

CBA has a long history in the field of transport projects. Still, its methodologies have been developed in a rather simple context which is now much more complex: is CBA still adapted to this context? CBA is now asked by decision makers not only to represent monetary flows and time savings, but also economic effects, social and distributive concerns, land use, climate change, and wider effects. It has to be implemented in a framework where private sector is involved and numerous entities are involved in project financing. Another strong evolution is that CBA has to interact more with public communication processes, and to take into account new types of governance. Adopting a Darwinian point of view, we consider the evolutions of CBA's environment, its resources and past adaptations. Then we pay attention to the potential competitors of CBA in this new environment. This analytical part is illustrated using several recent examples of new assessment questions and answers considered in France, at different scales: a great transport infrastructure scheme for the Parisian region, and the French national transportation infrastructure plan. They present more concretely how the new evaluative questions take form, and the kind of answers that have been found (or still have to be found). Building partly on the on-going evolution of the evaluation system in France, some ideas on the axes of adaptation of CBA will be presented in the last part of the paper, covering not only CBA's technical performance but also CBA's governance and integration in a more comprehensive assessment system.