TISBURY STW - Wastewater Treatment Plant in Tisbury, Wiltshire, England

TISBURY STW is a wastewater treatment plant located in Tisbury, Wiltshire, England, serving a population of around 4,310. The facility is situated in the rural county of Wiltshire, within the South West region of the United Kingdom. The plant provides secondary treatment, which is the standard level required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. With a designed capacity of 6,250 m³/day and an average discharge volume of 959.56 m³/day, the plant operates well within its capacity, ensuring effective treatment of domestic wastewater from the local community. The treated effluent is discharged into local watercourses that ultimately drain into the River Nadder, a tributary of the River Avon (Hampshire Avon). The River Avon flows into the English Channel via Christchurch Harbour. The receiving waters support diverse aquatic life and are part of a catchment that includes chalk streams of high ecological value.

TISBURY STW discharges into the River Nadder catchment, which feeds into the Hampshire Avon, a classic chalk stream known for its rich biodiversity. The River Avon flows south to Christchurch Harbour and the English Channel. The chalk stream ecosystem supports species such as salmon, trout, and otter, and is sensitive to nutrient enrichment. The plant's secondary treatment helps protect these downstream habitats.