DYSERTH STW STW - Wastewater Treatment Plant in St Asaph, Wales

DYSERTH STW STW is a wastewater treatment plant located in Dyserth, near St Asaph in Denbighshire, Wales. The plant serves a population of approximately 2,477 people and operates under the regulatory framework of the United Kingdom, which implements the EU Urban Waste Water Treatment Directive (91/271/EEC) for water quality standards. The plant provides secondary treatment, a standard level required for discharges into coastal waters under UK regulations. It has a designed capacity of 2,657.00 m³/day and currently treats an average daily flow of 551.47 m³/day. As a coastal facility within 10 km of the Irish Sea, the plant's discharge must meet stringent standards to protect marine environments. The treated effluent is discharged into local watercourses that ultimately drain into the Irish Sea. The surrounding area includes the Clwydian Range and Dee Valley, an area of outstanding natural beauty, and the discharge contributes to the ecological health of the coastal and marine ecosystems.

The plant's discharge enters local streams that flow into the River Clwyd and then into the Irish Sea near Rhyl. The coastal waters support diverse marine life, including fish, seabirds, and benthic communities. The area is ecologically sensitive due to its proximity to the Dee Estuary, a vital habitat for migratory birds and fish species. The plant's secondary treatment helps reduce organic pollutants and nutrients, mitigating eutrophication risks in the coastal zone.