Alvangens avloppsreningsverk - Älvängen Wastewater Treatment Plant, Sweden

Alvangens avloppsreningsverk is a wastewater treatment plant located in Älvängen, Ale kommun, Västra Götalands län, Sweden. It serves a population of approximately 5,800, classifying it as a small agglomeration under Swedish and EU regulations. The plant is situated inland, about 10-50 km from the coast, and plays a key role in local water management. The plant provides advanced treatment, which goes beyond the secondary treatment standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. With a design capacity of 9,000 m³/day and an average discharge volume of 910 m³/day, the facility operates well below its capacity, indicating room for future growth or seasonal variability. The treated effluent is discharged into a local watercourse that eventually drains into the Göta älv river system, which flows into the Kattegat sea. This downstream pathway underscores the plant's importance in protecting both local freshwater ecosystems and the marine environment of the Kattegat, a sensitive area supporting diverse aquatic life.

The plant discharges into a local watercourse that feeds into the Göta älv river, which flows through Västra Götaland before reaching the Kattegat sea. The Kattegat is a transitional marine area between the North Sea and the Baltic Sea, supporting important fisheries and migratory bird populations. Advanced treatment at this plant helps reduce nutrient loading, protecting downstream water quality and ecological balance.