Hadlow STW (Sewage Treatment Works) - Tonbridge and Malling, Kent, England

Hadlow STW (Sewage Treatment Works) is located in the village of Hadlow, within the Tonbridge and Malling district of Kent, England. The plant serves a population equivalent of approximately 3,399 and operates under the regulatory framework of the UK Environment Agency. As a secondary treatment facility, it provides biological treatment to reduce organic matter and suspended solids before discharge. The plant's designed capacity is 3,399 population equivalent, with a daily discharge volume of around 757 cubic meters. Under the UK's implementation of the EU Urban Waste Water Treatment Directive (now retained as UK law), secondary treatment is the minimum standard for inland plants serving populations between 2,000 and 10,000. Hadlow STW meets this requirement, ensuring compliance with environmental quality standards. The treated effluent is discharged into local watercourses that drain into the River Medway catchment, ultimately reaching the Thames Estuary and the North Sea. The plant plays a key role in protecting the water quality of the Medway basin, which supports diverse aquatic life and is used for recreation and agriculture. Its operation helps prevent nutrient enrichment and maintains the ecological balance of the downstream environment.

Hadlow STW discharges into the River Medway catchment, which flows through Kent and into the Thames Estuary, a major ecological and economic zone. The Medway supports diverse fish populations, including salmon and sea trout, and its estuary is an important habitat for migratory birds. The plant's secondary treatment helps control nutrient levels, reducing the risk of eutrophication in the sensitive estuarine environment.