Deckel Speidel Erdspeicher auf Rasen

Sewage charges

Let water seep away rather than money

You can save yourself the trouble

Wastewater costs arise, among other things, from the cleaning of wastewater and rainwater drained into the sewer system, the maintenance of the public sewer network and rainwater treatment and relief facilities. To cover these costs for wastewater and rainwater disposal, a wastewater charge was previously levied based on the amount of fresh water consumed. It was assumed that the amount of wastewater discharged into the sewer system for all properties roughly corresponded to the amount of fresh water consumed.

Various administrative courts have ruled that it is no longer permissible to levy charges based solely on this fresh water measure. Local authorities are now obliged to charge the costs of public wastewater disposal according to the polluter-pays principle, i.e. according to the amount of wastewater actually used.

From an ecological point of view, this creates an incentive for unsealing measures that promote a natural water cycle on the property and at the same time reduce the rainwater charge.

Property owners can also benefit economically by means of an infiltration system - and especially in the combination of rainwater utilization and infiltration - by partially eliminating fresh water fees and rainwater fees.

Split wastewater fee

As part of the introduction of a split wastewater charge, the previous general wastewater charge will in future be split into a wastewater charge and a rainwater charge. The wastewater charge covers the costs for the disposal of wastewater. As before, it is calculated according to the amount of fresh water used (EUR/m³). The rainwater charge covers the costs for the disposal of rainwater. It is calculated according to the size and type of sealing of the sealed (i.e. paved or built-over) surfaces from which rainwater is discharged into the sewer system (EUR/m²).

Sealed surfaces


The rainwater fee is due for directly discharging areas that have their own connection to the sewer system (e.g. via a gutter). Indirectly discharging areas that do not have their own sewer connection, but from which rainwater enters the street inlet shaft due to the slope of the terrain, for example, are also subject to charges. However, this also depends on the type of sealing (completely, heavily or lightly sealed), whereby this area is then weighted accordingly with a key figure (e.g. 0.8 or 0.4).

Free of charge

No fee is payable for areas from which no rainwater is discharged into the public wastewater system. There is also no charge for the infiltration of rainwater directly or in combination with a cistern. However, these areas should be specified separately.

Different regulations

The exact regulations and the possible area reductions can vary greatly from municipality to municipality. Please find out the details from your local authority or city so that you can achieve maximum savings.

Gummistiefel in einer Wiese



Into the ground instead of the sewer system

With a split wastewater fee, areas that are connected to cisterns without overflowing into the public sewer system are usually free of charge. The same applies if a correctly constructed infiltration system, such as a swale infiltration system or a infiltration system with infiltration shafts, is subsequently connected.




Reduce your wastewater charges

Retention cisterns have a throttled outlet and gradually discharge the rainwater into the sewer system. This relieves the public sewer network. This often brings financial benefits when calculating the sealed area and therefore the rainwater charge. Retention systems are often prescribed in new development areas. Both cisterns with a complete retention volume, where no rainwater utilization is possible, and retention tanks with a usable volume of 50% rainwater utilization, for example, can be installed. Half of the tank contents can then be used, while the other half flows off at a reduced rate.

Rainwater disposal via
infiltration, sewer connection or retention:

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