The Sickla plant is currently used for primary treatment of the wastewater passing through the plant. Primary treatment of the wastewater from two major in the tunnels known as the Farsta Tunnel and the Årsta Tunnel* in our business takes place here. All Söderort wastewater is brought here for treatment via these tunnels.
Pre-sedimentation of wastewater also takes place at Sickla. Pre-sedimentation involves filtering out urine and faeces from the wastewater.
We then send the water – which is still dirty – on in a tunnel to the Henriksdal treatment plant, where the wastewater undergoes the remaining treatment stages.
*The fact that the tunnels are named after urban districts does not mean that the Årsta Tunnel only carries wastewater from Årsta, for example – all Söderort wastewater and some of the inner city wastewater is carried in this tunnel as well.