Habia Culvert, France

Removing the culvert will allow endangered white-clawed crayfish to access refuge areas upstream.


The Arberoue River shelters trout and native white-clawed crayfish. The Habia Culvert blocks their natural migration as the upstream area is currently not colonised by crayfish. Removing the barrier will allow them to access refuge areas upstream in the watershed. This area has been targeted by the project team to save this endangered crayfish species.

At a glance

Project typeDam removal (demolition)
Project statusComplete
Date of removalOctober/November 2023
Km opened2.1
Focal speciesBrown trout and crayfish

Project context and opportunity

This project is part of a larger, ambitious project to protect and restore small local streams. The project team works with the barrier owner (a cow farmer), who has been working on:

– installing fences on all the meadows to avoid trampling by cows (with installation of remote watering troughs);

– planting hedges to limit soil and nutrient erosion into the river.

Project aims

The barrier removal will reopen 800m of river upstream and 1.3km of tributaries, for a total of 2,1 km.  Downstream, the next obstacle, “Moulin du chateau,” is located at 6.5km (all this linear is colonised by crayfish). In this context (crayfish and trout conservation), these small streams are as crucial as the mainstream. The expected results are:

– restored upstream accessibility for trout ;

– improved connectivity of the native crayfish population with other populations present in nearby tributaries.

Project achievements

Following the award of the grant, all necessary tasks to prepare for the project have been successfully completed. This includes conducting field measurements to assess the topography and dimensions of the dam, consulting with work companies to ensure optimal pricing and quality, and obtaining definitive authorisation for the work on June 19, 2023. The dam removal commenced from October 24 to October 25, involving removing the culvert and restoring the riverbed. Despite encountering challenges such as heavy rainfall, the project was executed efficiently and effectively, resulting in the successful removal of the barrier.