Wastewater treatment plants

Our six wastewater plants treat around 620,000 cubic metres of wastewater a day during dry weather. The plants are equipped with biological treatment stages, including stages to reduce phosphorus and nitrogen.

In the wastewater plants, the wastewater passes through a mechanical treatment stage with rake, grit chamber and sedimentation tank, followed by a biological treatment stage with anaerobic, anoxic and aerobic zones where phosphorus and nitrogen compounds are removed biologically. 95 percent of the undissolved and biologically degradable dissolved pollutants are removed. The treated wastewater is finally discharged into rivers and lakes.