Sediment replenishment : a few feedbacks on implementation and monitoring issues

Sediment replenishment (or gravel augmentation) is becoming a popular restoration measure in rivers affected by a sediment deficit and paved, notably in the Alps and their surroundings. The aim of this talk is to introduce a few examples where this measure has been experimented focusing on feedbacks to learn from these experiences and promote adaptive management. We will explore the justification and the critical questions operators are faced to when implementing such actions, such as the amount of sediment needed, the frequency of injection, the design of injection, the available sediment sources, the risks associated with such measures and their potential benefits. Some challenging issues will be introduced in term of monitoring design with the development of active and passive RFID technology to survey gravel mobility and large-scale regional approach to move from opportunistic to targeted actions.

Short Bio :
Hervé Piégay is Research Director at CNRS – National Centre of Scientific Research, ENS of Lyon, France. His research interests range from river contemporary changes to process monitoring  and characterisation of fluvial corridors by ground and airborne imagery. He is involved in integrated sciences for rivers and is strongly interacting with practitioners (Water Agencies, Regions, Ministry of Ecology, ONEMA, Compagnie Nationale du Rhône, EDF) providing knowledge for river management, planning and restoration and methodological frameworks and tools using GIS and remote sensing. Since 2010, he is the research leader of the scientific team working on the Rhône valley, being in charge of the Rhône Observatory of Human and Environment Interactions.