MARNHULL STW Wastewater Treatment Plant, Marnhull, Dorset

MARNHULL STW is a wastewater treatment plant located on Common Lane in Marnhull, a village in Dorset, England. The plant serves a population of around 5,515 people, placing it in the small agglomeration category under UK and EU classification systems. As a small-scale facility in England, MARNHULL STW is subject to the Urban Waste Water Treatment (England and Wales) Regulations 1994, which transpose the EU Urban Waste Water Treatment Directive. For agglomerations of this size, appropriate treatment is required to protect receiving waters, with secondary treatment being the standard expectation unless a less sensitive environment is designated. The plant discharges into the local catchment of the River Stour, which flows through Dorset and ultimately into the English Channel via Christchurch Harbour. The Stour supports diverse aquatic life and is an important river for the region's ecology. The plant's operation helps maintain water quality in this sensitive chalk stream environment.

MARNHULL STW discharges into the River Stour catchment, a chalk stream system that flows through Dorset to Christchurch Harbour and the English Channel. Chalk streams are globally rare and support diverse aquatic life, including salmonids and invertebrates. The plant's treatment performance is critical to preserving the ecological health of this sensitive watercourse.