the withdrawal of service water that is used and has to be treated separately and discharged as waste water is invoiced with 0,0353 €/m³ (waste water is invoiced separately by the operator of the wastewater treatment facility). for water that has been removed, warmed-up and discharged again into the canal the invoice value is 3.3% of that amount. the fees cover the costs that appear from operation and maintenance of the pumping stations and other costs related to the water services.