Killearn Waste Water Treatment Works - Secondary Treatment Plant in Dumgoyne, Scotland

Killearn Waste Water Treatment Works is a municipal wastewater facility located near Dumgoyne in the Stirling council area of Scotland, United Kingdom. The plant serves a population of approximately 1,607 people and operates under the regulatory framework of the Scottish Environment Protection Agency (SEPA). As a secondary treatment plant, it provides biological treatment to reduce organic matter and suspended solids before discharge. The plant has a designed capacity of 1,900 m³/day and currently treats an average daily flow of 357.77 m³/day, indicating significant spare capacity. Under the EU Urban Waste Water Treatment Directive (91/271/EEC), which the UK transposed into national law, agglomerations of this size (under 2,000 population equivalent) are typically required to provide appropriate treatment, and secondary treatment meets this standard. The plant's operation is subject to SEPA's regulatory oversight, ensuring compliance with discharge standards. The treated effluent is discharged into a local watercourse, likely a tributary of the River Forth or the River Clyde, given the location in the Central Belt of Scotland. The receiving waters ultimately drain into the Firth of Forth or the Firth of Clyde, both of which are important estuarine environments supporting diverse aquatic life and migratory fish species. The plant plays a key role in protecting these downstream ecosystems from nutrient pollution and pathogens.

The plant discharges into a small watercourse that flows through the rural landscape of Stirlingshire, eventually joining the River Forth or the River Clyde system. These rivers drain into the Firth of Forth and Firth of Clyde respectively, both of which are ecologically significant estuaries that support salmon, sea trout, and a variety of bird species. The area is part of the wider Forth and Clyde catchment, which is designated as a sensitive area under the EU Urban Waste Water Treatment Directive due to its importance for aquatic life and nutrient management.