If you wish to discharge wastewater into a private wastewater treatment system, you may be exempted from the requirement to obtain a discharge permit under certain conditions.

For certain industries and activities (such as the chemical industry, paper manufacturing, metal processing, and cooling water use), the wastewater is expected to contain pollutants that cannot be adequately treated at a municipal wastewater treatment plant. Requirements for this are specified in the industry-specific annexes of the Wastewater Ordinance.

To comply with these requirements, special measures and wastewater pretreatment systems are necessary to reduce the pollutant load to such an extent that the wastewater can subsequently be treated without harm in a public or private wastewater treatment plant.