B_AU FES STW STW Wastewater Treatment Plant, Blaenau Ffestiniog, Wales

B_AU FES STW STW is a wastewater treatment plant located on Pencefn Road in Blaenau Ffestiniog, Gwynedd, Wales. It serves a population of around 4,035 people, classifying it as a small agglomeration under UK and EU regulatory frameworks. The plant is situated in a rural, upland area of Snowdonia National Park. The plant provides secondary treatment, which is the standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for freshwater discharges from agglomerations of this size. The designed capacity is 5,195 cubic meters per day, with an average daily discharge volume of 898 cubic meters, indicating ample headroom for current loads. As a UK facility, it operates under permits issued by Natural Resources Wales (NRW), which set conditions for effluent quality and environmental protection. The treated effluent is discharged into the local river system, which flows through the Dwyryd catchment and eventually reaches Cardigan Bay in the Irish Sea. This coastal discharge point is within 10 km of the coast, making the plant subject to additional scrutiny under the Directive's requirements for sensitive areas. The receiving waters support diverse aquatic life and are important for migratory fish species such as salmon and sea trout.

The plant discharges into the Dwyryd river system, which flows into the Dwyryd Estuary and then Cardigan Bay, a Special Area of Conservation (SAC) designated for its marine habitats and species. The estuary supports important bird populations and is a nursery ground for fish. The plant's secondary treatment helps protect these downstream ecosystems from nutrient enrichment and organic pollution.