Start of work to restore ecological continuity at the Maziéras mill

September promises to be a highlight of the 2025 action of the Périgord-Limousin Regional Natural Park, with the launch of a major project to restore the ecological continuity of the watercourses, at the level of the Maziéras mill.

Restore the free flow of water

The objective of the work, which will begin the week of September 22, 2025, is to restore the Malencourie River to its natural functioning, by restoring the free flow of water, sediments, and aquatic species. The work will take place in two stages, with the first phase this fall to drain the structure and prepare the riverbed for restoration. The second phase, scheduled for 2026, will focus on the recirculation of the Malencourie in the old body of water, as well as on the dike consolidation which today serves as a municipal road.

This project is a continuation of the actions already carried out in the basin for more than ten years in the Dronne region, particularly within the framework of the LIFE Haute Dronne project led by the Park. The project benefits from the financial support from the Adour-Garonne Water Agency, from the European fund Open Rivers Program relayed by ENR France, and the Community of communes of Périgord Nontronnais. Partnerships which demonstrate thecollective commitment to the protection and restoration of our rivers.

Why restore ecological continuity?

For centuries, rivers have been punctuated by weirs and dams linked to human uses (mills, ponds, water intakes, etc.). These structures, although they are part of our heritage, modify the regime of watercourses and create breaks called "obstacles to ecological continuity". In particular, they prevent the free movement of fish (migration, reproduction, access to growth areas and refuge zones), the natural transit of sediments, essential to the balance of the river bed and the mixing of the water, which helps maintain temperatures suitable for aquatic fauna.

These impacts are now accentuated by the abandonment of the management of the worksWhile regular exploitation used to limit certain negative effects, the gradual withdrawal of this management from the territory has led to an increasing worsening of dysfunctions. Restoring ecological continuity therefore makes it possible to reopen aquatic environments and find more vibrant and resilient rivers.

Expected profits from the Maziéras mill

The opening of the Maziéras mill sill will have several positive effects. They will allow promote the free movement of fish, and in particular the brown trout, an emblematic species of our rivers, which will thus be able to find its reproduction and growth habitats both upstream and downstream. Furthermore, the restoration of ecological continuity will make it possible to reduce thermal impact of the mill's water body. By limiting the formation of stagnant and heated water in summer, the river will regain cooler conditions, essential for aquatic wildlife. Finally, the work carried out will contribute to restore natural habitats linked to the watercourse. Thus, the restoration of sediment transit will restore to the riverbed its diversity of substrates (gravel, pebbles) favorable to invertebrates and spawning grounds.

More generally, it is a general improvement of the ecological quality of the watercourse which is expected. A reconnected river is indeed more resilient to episodes of drought and heat waves, and contributes to maintaining biodiversity. Beyond its ecological benefits, the restoration of continuity at the Maziéras mill also contributes to enhancing the local natural heritage.

This project is part of a broader dynamic of balanced management of water and aquatic environments, serving residents, river users and future generations.

Below: On the left the current state of the site / On the right the expected state following the work (simulations)