Fluvial dynamics and water quality

Fluvial dynamics and water quality

The aim is to study changes in the river and its banks. Monitoring enables us to understand how water quality and the shape of the river change during restoration work.

Main questions

  • What is the impact of dam removal on water, sediment and chemical flows?
  • What changes will there be to the morphology of the river and its banks?
  • How will water quality in the Selune change?

Scientific objectives

Dams are physical barriers to the flux of water, sediment and dissolved chemical elements. A good understanding of these fluxes is necessary to understand the changes associated with dam removal.

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Monitoring station downstream of the dams - credit: O Fovet © Ophélie Fovet

Changes in water, sediment and dissolved element flows

In particular, it is necessary to identify the origin of the fluxes and to measure their intensity in order to be able to interpret the transfer processes, the role of hydrodynamic conditions and seasonal or exceptional variability (floods). Parameters such as flow, turbidity and chemical element content (nutrients) are monitored using automatic probes deployed upstream and downstream of the Selune dams.

 

River shape and dynamics

Lastly, the consequences for the shape and stability of the riverbed are also among the key questions concerning the consequences of dam removal. Geomorphological dynamics and sediment transport are monitored using LIDAR imagery and electronic tracing (PIT-tag) of coarse elements.

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Tools for monitoring river dynamics in the field - credits: A Crave and P Vrchovsky © Alain Crave et Paul Vrchovsky