Llanrwst STW (Llanrwst, Conwy, Wales) - Secondary Wastewater Treatment Plant

Llanrwst Sewage Treatment Works (STW) serves the town of Llanrwst in Conwy County, Wales, United Kingdom. The plant provides secondary treatment for a population equivalent of around 3,823, classifying it as a small agglomeration under UK wastewater regulations. As a secondary treatment facility, Llanrwst STW employs biological processes to reduce organic matter and suspended solids. The plant has a designed capacity of 4,072 cubic meters per day, with an average daily discharge volume of approximately 851 cubic meters. It operates under the UK's Urban Waste Water Treatment Regulations, which transpose the EU Urban Waste Water Treatment Directive, requiring secondary treatment for discharges to freshwater and estuaries. The treated effluent from Llanrwst STW is discharged into the River Conwy, which flows northward through the Snowdonia National Park and into Conwy Bay, part of the Irish Sea. The river supports diverse aquatic life, including salmon and sea trout, and the surrounding area is ecologically sensitive due to its proximity to protected habitats.

Llanrwst STW discharges into the River Conwy, which flows through the Conwy Valley and enters Conwy Bay, a coastal inlet of the Irish Sea. The river supports salmonid fisheries and diverse aquatic ecosystems. The downstream environment includes estuarine habitats that are important for migratory birds and marine life. The plant's secondary treatment helps protect water quality in this sensitive watershed.