Muirkirk STW - Secondary Wastewater Treatment Plant in East Ayrshire, Scotland

Muirkirk STW (Sewage Treatment Works) is a municipal wastewater facility located in the village of Muirkirk, East Ayrshire, Scotland. The plant serves a population of around 1,795 residents, making it a small-scale treatment works typical of rural communities in the region. The plant provides secondary treatment, which is the standard required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. Secondary treatment involves biological processes to reduce organic matter and suspended solids. The plant has a designed capacity of 5,000 cubic meters per day, with an actual discharge volume of approximately 400 cubic meters per day, indicating ample headroom for future growth. The treated effluent is discharged into local watercourses that drain into the River Ayr, which flows westward to the Firth of Clyde. This water body supports diverse aquatic life and is important for local biodiversity. The plant's operation helps protect the river's water quality and the downstream marine environment.

Muirkirk STW discharges into the River Ayr catchment, which flows through East Ayrshire to the Firth of Clyde on Scotland's west coast. The river supports salmon and trout populations and is a designated freshwater fishery. The plant's secondary treatment reduces organic pollution and nutrient loads, helping to maintain the ecological health of the river and the downstream Clyde estuary.