Drinking Water Ordinance - what it demands

The Drinking Water Ordinance (TrinkwV) in Germany is to a large extent an implementation of the EC Directive on "Water Quality for Human Use" (98/83 / EC) into national law. In addition, there are in the TrinkwV even more extensive provisions. What the TrinkwV in Germany regulates everything is explained here.

Limit values ​​in the TrinkwV

The TrinkwV distinguishes between limit values ​​for the following groups of substances:

  • biological pollution
  • chemical contamination
  • indicator parameters

For most chemicals, the principle of the maximum limit is followed. This means that a concentration is determined which, even with continuous use in the usual amount, does not produce harmful concentrations in the human body.

However, the complexity of pesticides necessitated a revision. Plant protection products may interact with each other, the health effects of which can not be determined in detail.

For pesticides, therefore, the so-called detection limit applies: With normal measuring methods in the laboratory, the limit of measurability can not be reached simultaneously for no more than 5 substances. The introduction of the detection limit is also known as the so-called zero principle.

In the case of biological contamination, ie bacteria in drinking water, detection is difficult and complicated. For most germs there is a limit of 100 cfu / 100 ml. 1 cfu is a colony-forming unit.

Some dangerous germs should not be detectable in drinking water. These include, for example, coliform pathogens. Some germs - as well as some substances - serve as indicators and, when present, require further action.

Responsibility for drinking water quality

The TrinkwV regulates the responsibility for the quality of the drinking water in the following form:

Up to the house connection line - usually the main tap in the cellar - the water supplier carries the responsibility for the water quality, from this point then the owner of the water installation. This is usually the owner of the building.

Exceeding the limits - no matter in whose responsibility - is always reportable to the health department. The health authority then decides on further measures to be taken, including under the Infection Protection Act, such as Legionella.

Special protection against Legionella

Owners of public buildings and, in certain cases, homeowners of a multiple dwelling who do not use their own building are required to take regular samples. Exceeding the limit values ​​for the legionella test is also to be reported here to the health authorities.

Exceptions to limits

According to the current version of the TrinkwV, the health authorities are authorized, in special cases, to grant a three-year, temporary exception for exceeding the limit value.

However, this only applies to chemical limit values ​​and only if the cause has been determined or known, and there is no health risk.

monitoring obligations

The Drinking Water Ordinance also regulates in great detail which water supplier of which order of magnitude has to examine which parameters at which regular intervals.

Buildings that self-supply themselves must undergo a microbiological examination each year. The period of time and the type of chemical parameters that need to be investigated is determined by the relevant health authority.

Area of ​​application

The drinking water standard applies only to drinking water - table waters and medicinal waters are excluded from the regulations. Both have their own regulations.

water hardness

The water supplier has to carry out a determination of the water hardness and to inform his customers on demand of the currently valid value.

In many cases, stickers for the washing machine are also issued free of charge in order to simplify the dosage of detergents.

Limit for the pH value

In the annex to TrinkwV also a limit value for the pH value of the drinking water is specified. It can be found under the point Hydrogen ion concentration. This is the chemically correct name for the acid value. It must be between 6.5 and 9.5.

The pH value is significantly influenced by the mineral content of the water.

Mandatory hazard analysis

The TrinkwV prescribes a risk analysis to every owner of an installation. Experts will need to draw up a detailed analysis of potential hazards based on the blueprints and measured parameters.

In particular, when limit values ​​are exceeded, for example in the case of a Legionella infestation, the health authority may also demand a comprehensive risk analysis relating to the respective parameter as a measure.

Hazard analyzes require a lot of expertise and experience and are usually carried out by specialized GWH companies. Finally, the hazard analysis also includes so-called maintenance planning, which must be strictly adhered to by the owner of the plant.

Different perception of the water examinations

While many consider the numerous and detailed surveys of drinking water to be too strict and over-coated, many are convinced that the regulations are too limited.

In particular, existing strains such as hormones in drinking water are viewed with concern by many. A removal of female hormones from the drinking water is technically theoretically possible, but overall too uneconomical.

Even with drug residues in drinking water, there is a similar controversy. So far scientists do not see any acute health risks in the measured concentrations. This is doubted by many.

Tips & Tricks

The quality of the drinking water in Germany makes drinking tap water harmless.

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