Industrial and commercial waste water

Over the past 60 years, many measures have been implemented to reduce the amount of pollutants from industry and commerce in our water bodies. Today, the challenge for enforcement agencies is to set appropriate standards for the many different pollutants in industrial waste water.

In Switzerland, numerous industrial and commercial processes are carried out in which a large number of products or chemicals are used. Some waste water is produced in the process. Depending on the industry, and on the process and products or chemicals used, different substances end up in the industrial waste water. These might be residual amounts of chemicals; reaction and degradation products; pollutants such as heavy metals; oil and grease residues; organic solvents or even active substances such as medicines and/or pesticides.

State-of-the-art waste water treatment

Depending on their properties, these chemicals can disrupt the operation of waste water treatment plants, contaminate water and harm aquatic life. The Waters Protection Ordinance therefore requires industrial and commercial enterprises to modernise and optimise their production and waste water treatment processes in such a way that as little waste water and as few pollutants as possible are produced.

These processes (e.g. production without waste water, neutralisation, oil separators, heavy metal precipitation) must be technically feasible and economically viable. In principle, however, certain requirements (e.g. for individual substances such as heavy metals or sum parameters such as total hydrocarbons) must be met before industrial waste water can be discharged into the sewers or a water body.

Intercantonal factsheets and VSA enforcement guidelines

The requirements of the Waters Protection Ordinance are designed to ensure that as few as possible of the large number of pollutants – over 10,000 are known – end up in water bodies. This regularly presents the authorities and businesses with a range of challenges. They need to determine which pollutants are contained in the waste water, which enter the water bodies, how this can be monitored and what industrial plants can do to remove these pollutants. The intercantonal factsheets and VSA guidelines on the state of the art in various sectors and processes are a valuable aid in this respect. They set out general harmonised requirements for industrial waste water discharge into water bodies throughout Switzerland.