Chalgrove Oxon STW - Secondary Wastewater Treatment in South Oxfordshire, England

Chalgrove Oxon STW is a wastewater treatment plant located in Chalgrove, South Oxfordshire, Oxfordshire, England. It serves a population of approximately 3,040 and is part of the region's municipal wastewater infrastructure. The plant is situated inland, away from coastal areas, and operates under the regulatory framework of the United Kingdom. The plant provides secondary treatment, which is the standard biological treatment process required for agglomerations of this size under the EU Urban Waste Water Treatment Directive (91/271/EEC), as retained in UK law. The designed capacity is 3,058 m³/day, and the current discharge volume is 676.81 m³/day, indicating operational capacity well below design limits. The plant is operated as part of the UK's water industry, regulated by the Environment Agency. The treated effluent is discharged into local watercourses that drain into the River Thames catchment, ultimately reaching the North Sea. The plant plays a key role in protecting the water quality of the Thames basin, supporting aquatic life and downstream ecosystems. Its secondary treatment ensures compliance with environmental standards for organic matter and suspended solids.

The plant discharges into local streams that feed into the River Thames, which flows through southern England into the North Sea. The Thames basin supports diverse aquatic habitats and is an important ecological corridor. The plant's secondary treatment helps maintain water quality in this sensitive river system, reducing nutrient and organic pollution that could otherwise impact downstream environments.