4. Conclusion

This overview of running water ecosystems and their evolution under human influence shows their richness and fragility. Scientific and technical knowledge has progressed enormously in a number of areas: their functioning, their ecology, but also the definition of relevant and operational quality indicators. Numerous ecological engineering tools and methodologies exist and can be implemented in ecological restoration programs. Financial and regulatory resources are in place, although the scale of the degradation that has accumulated over the decades (and is still continuing) would require more resources.

The current state of French rivers is generally unsatisfactory, with around 2/3 of French surface water bodies at risk of failing to meet the WFD target of good ecological status by 2027. The task is therefore vast and urgent. However, it is essential to be clear...