The presence of ecological functions testifies to the health and integrity of any stream. The incorporation of such functions into neglected, polluted, denaturalized urban water courses is indicative of successful restoration. As a return to original state is not always possible, however, projects that do not reestablish all ecological functions but accommodate some of them are still commendable. Where certain city’s dense urban fabric is too constrained to permit the insertion of a completely natural stream, there are still ways to integrate come degree of ecological functions, especially in considering the long-term possibility of restoration work.

Urban stream restoration projects that incorporate such functions have the potential to change the way people experience the urban environment. By reintroducing flowing water, reestablishing exchange with groundwater and recreating wildlife habitat, stream restoration projects can reintegrate natural processes not usually found in cities. The presence of such processes can improve urban life in numerous ways as well as foster greater human appreciation of the natural world.

This thesis set out to identify key criteria in successful urban stream restoration, to determine the degree to which ecological functions could be achieved in an urban environment, and to examine how and why this should be achieved with the Bièvre in Paris. Chapter One establishes ecological functions as means of evaluation and examines their role in two cities that incorporate them into their dense urban fabric. Chapter Two introduces the Bièvre and describes its excessive exploitation over two millennia, suggesting the need to restore it. Chapter Three explores the evolutions and nature of the restoration efforts leading to the current project to restore the Parisian stretch. Chapter Four examines attention to ecological functions in two different approaches to the Parisian project. Chapter Five gives the current state of the project and the elements on which its implementation depends.

The restoration of the Bièvre in Paris is an extraordinary project to recreate a former tributary of the Seine whose bed was utterly annihilated by successive embankments while its flow was diverted to underground pipes. While the initial plan for the project by the Atelier Parisien d’Urbanisme reveals very little attention to restoring the ecological functions of the stream, the recent study by the Institut d’Aménagement et d’Urbanisme de la Région Ile-de-France acknowledges the benefits and feasibility of such an approach. Nevertheless, the potential to recreate a stream accommodating the measures of successful stream restoration outlined in Chapter One does not alone justify its execution.

Examination of the potential benefits and incentives for urban stream restoration shows that such a project requires justification from numerous perspectives. While Parisian restoration is favorable in light of decades of prior restoration efforts and proven feasibility, political will for such an investment is lacking. This is unlikely to change unless greater human benefits for disrupting the city’s form are discovered and promulgated. Outside Paris, however, where such benefits are already being realized, restoration efforts are likely to proceed.