Ongoing

The Léguer River catchment is one of the most hedged areas in Brittany, but has suffered a decline in its hedgerow mesh as a result of agricultural mechanization and land consolidation operations. Faced with the degradation of the Leguer's water quality observed in the 1990s, elected officials in the watershed became aware of the need to preserve the hedgerow, and to consider its restoration to improve water quality. Since 1999, the Leguer's watershed committee undertook awareness-raising of the watershed population, before experimenting with the restoration of hedges and embankments in several pilot basins.

This work was then extended to the entire watershed, leading to the restoration of hundreds of kilometers of hedges and embankments. This action is still ongoing today (with new hedges planted every winter), however no longer managed at the whole basin scale but by different intermunicipalities.

It aims in particular to ensure the sustainability of existing linear thanks to urban planning tools and the promotion of hedged farmland.

A complementary action comes with the river management (as the Léguer is labellized "Wild River"), which includes riparian forest restoration to create shade on the river and reduction of the risk of water heating, purification processes, biodiversity of the watercourse, etc.

The developpment of agroforestry and intercropping is also being studied to further the agricultural practices evolution in the basin.

Headwater wet meadow (Saint-Évarzec, Finistère) where two drainage ditches short-circuited a hillside spring and routed nitrate-rich flows directly to the stream. In 2014, the ditches were infilled (north ditch partly to keep upstream runoff entering the meadow) and a small berm removed, with protected-species precautions. The short-circuit was eliminated: all slope water now crosses the wetland, maintaining high N removal; soil saturation increased and low-water levels rose slightly near the former ditch. Agricultural operability decreased (bearing capacity), so mowing is now feasible only in very dry years; the plot is used within a Brittany “pie-noir” grazing circuit.

However, the potential for agricultural exploitation since implementation is not as high as hoped, unlike the very satisfying hydrological effect : the meadow remans wet even during very dry years like 2022. The peaty wet part of the site is intentionally left to natural woodland succession (hoping for future understorey grazing), as it is not suitable for agricultural use otherwise.

The project owner/operator is the Communauté de communes du Pays Fouesnantais with RERZH technical support and monitoring. The costs were very low, an excavator hire for ~€560 and the rest of the works costs were included in the collectivity's budget (studies/monitoring covered by RERZH).

More recently, after the initial over-excavation and reuse of oxidised berms diverted part of the spring toward the southern sector, increasing waterlogging and limiting mowing, a corrective package created a small pond at the spring with overflow toward the peatier/northern side, resumed brush-cut mowing to restore a haying dynamic, and reinforced invasive nutria control in 2024.

Due to major developments over the past two centuries, the Eau Morte Valley (a tributary of Annecy Lake) has a hydrosedimentary dysfunction with incised areas and areas with sediment excesses and an alluvial marsh disconnected from flooding. To reduce the impacts of the river's floods on uses, and to prevent the risk of urban areas flooding, a functional restoration programme for the valley has been developed by the federation of municipalities of Annecy lake sources. It was based on the renaturation of the Eau Morte bed, the functional restoration of the Giez marsh and the construction of crossing structures. This work has given the marsh a role as a flood expansion area. This project was also carried out by involving local residents in a process of territorial dialogue so that they themselves would be actors in the area and would participate in its management.

Since 1984, the Ille-et-Vilaine Hunting Federation has been restoring a 550-ha peat marsh heavily drained and cropped in the 20th century. Maize fields were converted to hay meadows and pasture through agreements with farmers; a peat bog and a reedbed were restored; and water levels are artificially managed to enable winter flooding. The Méleuc was re-routed into a more natural course. The goals (improve staging conditions for migratory waterbirds and recover marsh functions (carbon sequestration, natural water purification)) have been met for bird use, while water-level management still needs optimisation. Recent sources add that the site forms part of the Ramsar “Bay of Mont-Saint-Michel” and its Natura 2000 network; roughly 380 ha are held by FDC35 and the Foundation for the Protection of Wildlife Habitats. A major reedbed project (“Bois de la Mare”) cleared poplar/spruce to restore ~16 ha of phragmites as compensation linked to the Mont-Saint-Michel maritime project, awarded France’s Ecological Engineering Prize in 2018. Management relies on mowing then grazing via agreements with about twenty farmers; hunting is excluded except targeted wild-boar control, and guided public activities are now offered. In 2021 the regional scientific council (CSRPN) issued a favourable opinion toward designation as a Regional Nature Reserve over a 768-ha perimeter (process ongoing). Winter counts report up to c. 6,000 anatids.