Compton Coo STW - Secondary Wastewater Treatment Plant in Compton, West Berkshire

Compton Coo STW is a wastewater treatment works located near New Farm in Compton, West Berkshire, England. The plant serves a population of approximately 2,750 and operates under the regulatory framework of the UK Environment Agency, which enforces standards aligned with the EU Urban Waste Water Treatment Directive (91/271/EEC). As a secondary treatment facility, it provides biological treatment to reduce organic matter and suspended solids before discharge. The plant has a designed capacity of 3,640 m³/day and currently treats an average daily flow of 612.25 m³/day, indicating significant spare capacity. Under UK regulations, secondary treatment is the minimum standard for inland freshwater discharges, and the plant's performance is monitored through discharge permits issued by the Environment Agency. The facility is part of Thames Water's regional network, though the specific operator is not confirmed. The treated effluent is discharged into a local watercourse that ultimately drains into the River Thames catchment. The Thames Basin supports diverse aquatic life and is an important ecological corridor in southern England. The plant's location in the rural West Berkshire area means its discharge contributes to the base flow of local streams, which are sensitive to nutrient enrichment.

The plant discharges into a tributary of the River Thames, which flows eastward through London and into the North Sea via the Thames Estuary. The Thames catchment supports a wide range of species, including salmon, trout, and eels, and is designated as a Site of Special Scientific Interest in many stretches. Nutrient loading from wastewater can contribute to eutrophication in slow-moving reaches, making secondary treatment with phosphorus removal increasingly important in sensitive areas.