Dam Removal Day: celebrate free flowing rivers: 2 new factsheets to understand dam and weir removals

“On Dam Removal Day, 8 October 2025, NGOs in France and Europe reaffirm their commitment to restoring waterways and removing obsolete artificial barriers. More than 1.2 million structures block the free flow of European rivers and weaken the biodiversity and resilience of aquatic ecosystems. It is estimated that more than 200,000 of these structures are unused, abandoned or obsolete. Most are small structures less than 3 metres high, such as sluice gates, weirs and culverts, which bear witness to past uses. Their cumulative impact on biodiversity and the functioning of watercourses is significant. These obstacles isolate vulnerable freshwater species already weakened by the effects of climate change, impact fish migration, and promote the deposition of fine sediments that clog the riverbed upstream of the structures, etc.”

(read press release , in french only)

To reaffirm the advantages of removing obsolete structures that have a significant impact, ERN has published two fact sheets on experiences of removal in France:

– Removal of large dams on the Sélune, 4 pages, May 2025, ERN (french only)

For over a century, the Vezins and La Roche-qui-Boit dams interrupted the natural course of the river. Their removal allowed the Sélune to return to its original bed and natural dynamics. The result of many years of debate and scientific studies, this project restored ecological continuity and improved water quality throughout the watershed. Supported by numerous organisations, it will be scientifically monitored until 2027.

The initial results are already very promising. Atlantic salmon, European eels and sea lampreys have returned, natural sediment transport has resumed and biodiversity is increasing.

– Removal of the Rhodes Bridge weir, 4 pages, May 2025, ERN (french only):

This document summarises the main stages and challenges of the project to remove the Rhodes Bridge weir, which has reconnected nearly 29 km of free-flowing rivers, benefiting local biodiversity and the quality of aquatic environments.

Vidéos and cases sutides on youtube chanel : Rivières Vivantes – Laisser Couler – YouTube