The effluent class determines the performance of a plant for the treatment of sewage

The effluent class determines the performance of a plant for the treatment of sewage. Each class describes the filter range of the respective plant required. For example, there are septic tanks, which mainly decompose carbon, while higher plants also treat ammonia and other substances.

Who determines the effluent class?

The effluent class required by the treatment plant that you can install on your property is determined by the responsible water authority. This is commonly called the “lower water authority“.

For most areas in Germany, the effluent class C is sufficient. For most areas in Germany, effluent class C is sufficient. However, which one is required depends on factors such as the location in a water protection area.

How do I know if my treatment plant is verified?

The Deutsches Institut für Bautechnik (DIBt) (German Institute for Structual Engineering) verifies septic tanks. It certifies all plants available in Germany. On the website of DIBt you can specify the certification number and get the document about the certification, which exactly corresponds to your plant. There you can also see whether the approval number of your own septic tank is still valid.

What exactly does the effluent class determine?

Water, which is used in the household, is referred to as sewage after use. In the absence of a connection to a sewer system, it is necessary to clean the sewage and drain the purified water. In order for the water to be drained into nature without risk, it must be of a certain quality. This quality is determined by the effluent class.

Overview of all effluent classes

Effluent class C

This effluent class is the lowest for septic tanks. It stands for the decomposition of carbon in the sewage. Since carbon compounds are organic compounds, it therefore regulates the decomposition of organic material in the waste water.

Effluent class N

Septic tanks with effluent class N include effluent class C as well as nitrification. The means that ammonium is converted.

This process requires a lot of oxygen, which is why simple plants can only implement this process to a limited extent.

Effluent class D

Septic tanks with effluent class D include effluent classes C and N. During the decomposition of ammonia, nitrate is formed. Nitrate is absorbed by many algae and boosts their growth. Septic tanks with drain class D convert nitrate into molecular nitrogen.

Effluent class +P

Septic tanks with effluent class +P include all of the effluent classes mentioned above. They use a chemical solution to separate phosphates from the water, which then sediments in the sludge.

Effluent class +H

Septic tanks with effluent class +H include effluent class D as well as the effluent classes mentioned above D. In this class, hygienization of water happens. After treatment with UV light, for example, it reaches bathing water quality and can also be drained into the water in built-up areas.