Pénélope Brueder, Alexandra Schleyer-Lindenmann, Corinne Curt, Franck Taillandier

In the context of intensification of flood risks, NbS propose an interesting approach to conciliate population’s protection and biodiversity. While this recently emerging concept has been the subject of numerous studies, there is still little work on this issue in social sciences. However, it is essential to understand the social representations of NbS in order to help authorities to overcome possible barriers to implementing more NbS projects for flood risk. As the opinions of experts eventually diffuse and come to shape the representations of the general public we decided to explore the social representation of NbS of flood risk experts. We interviewed 19 actors who can be divided into two groups: theorists and practitioners. These interviews were transcribed and analyzed using textual statistics and a qualitative analysis grid, in order to identify the main lines of discourse and how social representations are organized. Combining the two techniques is rather rare, but proves to be fruitful. The main findings of this work are that the social representations of the two groups of experts diverge and that the concept of NbS and the solutions it encompasses do not seem to represent the same social reality. The lack of collaboration between institutions and field actors is a major obstacle to the implementation of NbS projects. Finally, the social representations of the two groups of experts have a common basis which seems to be centered on cognitive biases such as the need to control risk and natural ecosystems, and the culture of civil engineering. Moreover, the results suggest that the expression “NbS” is not well suited to all actors.