A reed bed filter in Paris (Bois de Boulogne): analysis of the social and spatial integration of a boundary object

A stormwater system in the bois de Boulogne has deeply been renovated. Whereas it used to discharge rainwater from a section of the ring road directly into the Seine, the City of Paris took the opportunity to develop a green infrastructure (planted filter) for storing and treating this water. It is then discharged into the bois de Boulogne hydrographic network and eventually into the Seine. The Life Adsorb project aims at scientifically supporting and evaluating the effectiveness of the work, particularly to reduce micropollutants.

This study includes a sociological component which has analysed the conditions of appropriation of the structure by the technical services of the local government, as well as by the local residents and users of this frequented green space. In order to analyse the socio-spatial insertion of the filter, we used an analysis framework based on social acceptability, differentiating between the objective and the problem of acceptability. On the one hand, we studied the device as a socio-technical object which, from its design until it was put into operation, goes through different stages and reinterpretations (sociology of translation and innovation).

On the other hand, we observed how this infrastructure was interpreted by the visitors and the local residents of the green space, once it was built. Finally, the article illustrates the ambiguity between the desire to make this object a 'showcase project' of an innovative and sustainable city and the search for invisibility through landscaping.

The article illustrates that the filter can be considered as a boundary object at the intersection of the know-how and practices of the various services involved in its design and maintenance on the one hand, and of the users and the designers on the other hand. A framework integrated the different dimensions of social acceptability and appropriation is proposed.