LLANINA WWTW STW - Closed Wastewater Treatment Plant in Ceredigion, Wales

LLANINA WWTW STW is a former wastewater treatment plant located in Cei Bach, Llanllwchaiarn, Ceredigion, Wales, United Kingdom. The facility served a population of 5,515 and was designed with a capacity of 1.00, though it is now closed. As a closed plant, no current treatment process or operational details are available. Under the EU Urban Waste Water Treatment Directive (91/271/EEC), which the UK implemented prior to Brexit, agglomerations of this size (5,515 population equivalent) typically required secondary treatment. The plant's closure may reflect upgrades or consolidation within the regional wastewater network. The plant is situated near the coast of Cardigan Bay, part of the Irish Sea. Its discharge would have entered local watercourses draining into the bay, which supports diverse marine life including seabird colonies and cetaceans. The surrounding area is rural and sparsely populated, with the River Aeron and other small streams flowing into the bay.

The plant is located near Cardigan Bay, a marine inlet of the Irish Sea. The bay is ecologically important, supporting bottlenose dolphins, grey seals, and various seabirds. Local rivers such as the Aeron and Teifi drain into the bay, carrying freshwater that influences coastal habitats. The closure of the plant may reduce nutrient and pollutant loads to these waters, benefiting downstream ecosystems.