Viskafors avloppsreningsverk - Advanced Wastewater Treatment in Årbo, Sweden

Viskafors avloppsreningsverk is an advanced wastewater treatment plant located in Årbo, within Borås kommun, Västra Götalands län, Sweden. The plant serves a population of approximately 4,050 people and has a designed capacity of 9,500 m³/day, with a current discharge volume of 635.77 m³/day. As an advanced treatment facility, it goes beyond secondary treatment to remove nutrients such as nitrogen and phosphorus, which is typical for plants discharging into sensitive environments. Under the EU Urban Waste Water Treatment Directive (91/271/EEC), Sweden designates many water bodies as sensitive areas, requiring tertiary treatment for agglomerations above 10,000 population equivalent, though smaller plants like this one may also adopt advanced treatment voluntarily. The plant's treated effluent is discharged into the local watershed, which ultimately drains into the Kattegat via the Viskan River. This river supports diverse aquatic life and is an important migratory corridor for salmon and sea trout. The advanced treatment helps protect the river's ecological health and downstream marine environment.

The plant discharges into the Viskan River, which flows through Västra Götaland before reaching the Kattegat, a marine area of the North Sea. The river supports diverse aquatic life, including salmon and sea trout, and is an important migratory corridor. The advanced treatment reduces nutrient loading, helping to prevent eutrophication in the sensitive coastal waters of the Kattegat.