LE THEIL 2011 Wastewater Treatment Plant, Val-au-Perche, Normandie

LE THEIL 2011 is an advanced wastewater treatment plant located in Val-au-Perche, in the Normandie region of France. The plant serves a population of approximately 1,568 residents, reflecting its role in a small agglomeration within the Orne department. Its designed capacity of 3,500 m³/day indicates infrastructure scaled to accommodate local needs. The plant employs advanced treatment processes, which go beyond the secondary treatment standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. This level of treatment is typically implemented in sensitive areas to reduce nutrient loads and protect receiving water bodies. The plant's discharge volume of 279.73 m³/day suggests operational capacity utilization well below design limits. The treated effluent is discharged into local waterways that ultimately drain into the English Channel via the Huisne River and the Loire River system. The advanced treatment helps safeguard downstream aquatic ecosystems, including those in the Loire basin, which supports diverse fish populations and migratory species. The plant's inland location reduces direct marine impact, but its contribution to river water quality is significant for regional ecological health.

The plant discharges into the Huisne River, a tributary of the Sarthe River, which flows into the Maine and then the Loire River before reaching the Atlantic Ocean. The Loire basin is ecologically significant, supporting diverse aquatic life including Atlantic salmon and European eel. Advanced treatment at this plant helps reduce nutrient pollution, protecting downstream habitats from eutrophication and maintaining water quality for biodiversity.