Rainwater and river doctrine, techniques and design in the Paris' agglomeration, 1970-2015 ; La ville à fleur d'eau : doctrines, techniques et aménagements de l'eau de pluie et des cours d'eau dans l'agglomération parisienne, 1970-2015

Abstract

Since the 2010s, strategic local policies concerning urban resilience and biodiversity support are being promoted, focusing on ways to renew urban water management. Research points however, to the low effectiveness or efficiency of such urban environmental policies, and questions the need of renewing the relationship between the environment and the city. Other researches put forward that a major change occurs in urban rainwater management since the 1970s. We follow the idea of an ecological and climatic transformation of rainwater and urban rivers management since the 1970s. Three hypotheses underlie this thesis. First, based on ecological and climatic principles, a technical management doctrine transforms the urban water engineering. Secondly, urban hydrology has experienced a shift, carried out by new techniques. Thirdly, this technical doctrine has extended to urban planning and design. We tested the hypotheses by the study of a corpus of guides and technical documents produced between 1970 and 2015; of an inventory of techniques; and of five case-studies, completed with interviews with professionals. The study found that ecology is present, but as an auxiliary to sanitation principles. An ecological ethic is incorporated into technical doctrines : the use of living organisms in engineering is partially based their supposed superior effectiveness in spatial planning. The hydrology of the Paris metropolitan area seems to be marginally evolving. Urban neighborhoods are not transformed by water management : urban water spaces and facilities remain tenuous, discontinuous, underlying and preceded by other logics of spatial organization. ; Dans les années 2010, des politiques urbaines de résilience et de soutien de la biodiversité sont mises en avant, avec pour cœur une gestion renouvelée de l'eau en ville. Pourtant, les travaux de recherche font plutôt état d'une faible efficacité des politiques urbaines environnementales, et interrogent la désirabilité d'une réforme du rapport entre environnement et ville. Les ...