In late spring, the Haute-Sûre Forêt d’Anlier Nature Park applied for a demolition grant to reopen streams in the Forêt d’Anlier. The park received a €60,000 grant to help remove 11 priority barriers to ecological continuity. This is a milestone for the Open Rivers Programme, marking our first support for dam removal demolition work in Belgium.
Save Our Pearls!
The Forêt d’Anlier, one of Belgium’s largest deciduous forests, spans the communes of Habay, Léglise, Fauvillers, and Martelange, covering the watershed between the Rhine and Meuse basins. As part of the Natura 2000 network, it is home to numerous fragile species and habitats of European and global significance. Notably, the massif’s rivers host over 90% of Belgium’s pearl mussels.
Freshwater Pearl Mussel in the Forêt d’Anlier © PNHSFA
The pearl mussel, an endangered species on the IUCN Red List, faces higher extinction risks than iconic species like the Polar Bear or the Giant Panda. As a filtering organism, it retains up to 50% of particles passing through a watercourse, filtering between 40 and 80 litres of water per day and playing a crucial purifying role. Its atypical life cycle requires trout for reproduction, with mussel larvae developing in the gills of host fish. Low trout populations threaten the mussel’s survival, which is linked to significant ecological fragmentation.
Recent fish surveys show that trout populations are suboptimal in the massif’s waterways due to barriers preventing them from entering streams to spawn. This project aims to remove these obstacles, reopening streams for free circulation of wildlife and sediments.
A barrier for trout migration in Forêt d’Anlier © PNHSFA
Bridging the Gap
The Nature Park receives funding from the Walloon government for nature protection actions in the forest, but additional co-financing was necessary. The Open Rivers Programme grant arrived just in time.
In the coming days, 11 old culverts will be dismantled and bridges will be installed above the natural river bed, designed for forestry machinery passage. Unlike pipes and culverts, these bridges preserve the watercourse’s natural bed, size, and slope. Installation is dry, without cement or mortar, minimizing environmental risks. This project will reopen almost 28 km of high-quality streams, benefiting pearl mussels, brown trout, European sculpin, and brook lamprey.
The summer schedule promises to be very busy in the Forêt d’Anlier. This is only the first step, with the long-term goal of removing all obstacles to ecological continuity in these remarkable waterbodies.
