Integrated Flood Management Approach to Combine Urban Generated Floods and Ecosystem Services Preservation (PAP014678)

Código

PAP014678

Autores

Radojevic Biljana, Breil Pascal, Hassan Abbas

Tema

Urban Floods

Resumo

This article exposes a strategy for managing flood risk that would be implemented in areas that are prone to rapid urban expansion. We take here the opportunity of a well document periurban watershed (150 km2) located in the vicinity of Lyon city (France) and where large investments from national, regional and local authorities have been devoted since 2008 to reduce urban pollution sources and the hazard of hydrological extremes, flood and drought. These actions contribute to restore lost ecosystem services like bio-assimilation and transformation of organic substances improving global surface water quality, human health and providing societal economic benefits. Predicted urban development would however compromise these efforts in the near future. It means that rapid periurban development should integrate both flood management risk it generates for near densely urban system it grows around and preservation of new stream water ecosystem it affects.To address this issue, we develop on this periurban watershed a probabilistic based hydrological modeling of its flood regime. Only the landscape change is considered at this stage, arguing here that climate change will have less impact on the mid-term horizon of 2030. Main working hypothesis is to assume on-site rain water retention implementation for new constructions expected on 2030. This is to increase flexibility in controlling urban floods. A constraint is however to maintain occasional overflows from sewer systems to ensure protection of downstream dense urban areas against pluvial flooding. At the same time we consider to prevent receiving stream ecosystems from geomorphic and water quality damages as to keep ecosystem services working.