The Tardoire, from its source in the commune of Châlus to the brook of Suchés, has a total length of 114 km, it drains a catchment area of 1200 km². Part of the spring is tapped for drinking water supply. It flows on a crystalline base up to Montbron and then on limestone soil where it loses part of its water in the karsts.
All hydraulic structures on this watercourse are concerned by this regulation to ensure ecological continuity.
The SYMBA Bandiat-Tardoire has taken on the role of project manager for the restoration of ecological continuity on four structures on the Tardoire. These structures were selected because they have the greatest impact on ecological continuity and the quality of the environment (large size of the structures, long zones of influence, etc.), because their administrative and regulatory situation is more cumbersome than that of small weirs.
The alteration of the hydromorphology of the Tardoire and the disruption of ecological continuity have been targeted as degrading factors of the ecological status of the aquatic environment. To achieve the objectives of good status and also to support the owners, the SYMBA Bandiat-Tardoire has carried out a global study for the restoration of ecological continuity on 13 structures of the Tardoire from 2017 to 2020.
These sites are located on the “Tardoire” water body, classified as having a medium ecological status with a good status objective for 2027.
We have been in contact with the owners for several years and they have given us their confidence for this project. The site of the Buisson forge with a weir having a head of 2.6 m is very representative of the cumulative impact of disorders (incision, upstream sediment accumulation, fish continuity, upstream tributary connection, etc.). The common will to move towards a removal of the dam ensures a major interest in the actions already carried out in this direction.
Other actions have been and are being carried out by the syndicate, such as the restoration of wetlands, the removal of water bodies, etc., which also contribute to achieving good water status. The future watercourse management programme currently being drawn up will tend towards similar actions with the common objective of good water status.
|Location||Communes of Chéronnac and Champagnac-la-rivière in the Haute-Vienne department|
|Km of river opened up||29.8|
|Target species||European eel, brown trout|
|Removal date||November 2022 / April - May 2023|
The removals will significantly improve the morphology and natural functionality of the Tardoire. As a result, it will improve aquatic habitats, which will be more diversified and better oxygenated, and water quality by acting on parameters such as temperature and the dilution factor.
The project will also allow the free migration of fish species in the river. The target species identified are European eel and brown trout.
The removal of these structures will free up a significant 18.60 km of watercourse for these 4 structures; in conjunction with the removal of the weir directly downstream carried out in 2017 (Puybonland mill); and also allow reconnection with the tributary La Colle (over 3.20 km).
Overall, the ecological status of two bodies of water, “La Tardoire from the confluence of the Colle to the confluence of the Bonnettes” and “Ruisseau de la Colle”, will be improved, as well as the ZNIEFF.