DRUMNADROCHIT WWTP - Secondary Treatment Plant Serving Lewiston, Scotland

DRUMNADROCHIT WWTP is a municipal wastewater treatment facility located near Lewiston in the Highland region of Scotland. The plant serves a population of approximately 1,417 people and is situated on the shores of Loch Ness, one of the most iconic freshwater bodies in the United Kingdom. The plant provides secondary treatment, which is the standard biological treatment stage required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for inland discharges of this scale. With a designed capacity of 2,250 cubic meters per day and an average daily flow of around 315 cubic meters, the facility operates well within its capacity. Treated effluent from the plant is discharged into Urquhart Bay, a shallow bay on the northwestern shore of Loch Ness. Loch Ness drains via the River Ness into the Moray Firth and ultimately the North Sea. The loch supports a diverse aquatic ecosystem, including Atlantic salmon and brown trout, and is a key part of the River Ness Special Area of Conservation.

The plant discharges into Urquhart Bay, which flows into Loch Ness, the largest lake by volume in the UK. Loch Ness is part of the River Ness catchment, which drains into the Moray Firth, a large coastal inlet of the North Sea. The loch and its tributaries support populations of Atlantic salmon, sea trout, and European eel, and the area is recognized for its ecological importance as a migratory corridor and spawning ground.