Unraveling the effects of climate change and flow abstraction on an aggrading Alpine river

Séminaire de Maarten Bakker (Université de Lausanne), Jeudi 5 Octobre 2017 à 11h en Salle OSUG-B 105

Summary : Climatic warming and associated glacial retreat may have a large impact on sediment release and transfer in Alpine river basins. In parallel, the sediment transport capacity of many European Alpine streams is affected by hydropower exploitation, notably where flow is abstracted but the sediment supply to the headwaters is maintained. Here, I present the case-study of the Borgne River (Switzerland), where we reconstructed the historical evolution of bed level change and sediment transfer based on a unique dataset derived from SfM archival photogrammetry and flow intake management data. We then used bed load transport capacity calculations and climate data to assess the role of flow abstraction and climate change in the system evolution. Despite the large-scale flow abstraction, we find that climate-driven sediment supply may propagate downstream through these Alpine streams and force morphological response.

Séminar by : Maarten Bakker (Université de Lausanne)

Animation : F. Gimbert (GLACE)