The public utility Stadtwerke Mainz has undertaken to reduce its water prices (excluding taxes and duties) by approximately 15% with effect from 1 January 2013. The price reduction is based on the 2010 price level and will apply until 2019. In a commitment decision issued today the Bundeskartellamt has declared the commitments made by Stadtwerke Mainz to be binding.

Andreas Mundt, President of the Bundeskartellamt, stated: "On the basis of this decision the water customers of Stadtwerke Mainz can expect to save approx. € 4.5 million per year, i.e. a total of more than € 31 million over the total duration of the commitment. This significant reduction in water charges in Mainz demonstrates the efficiency and effectiveness of the review of water prices under competition law. As Stadtwerke Mainz was open to dialogue, a quick settlement could be achieved which has also been to the benefit of consumers."

According to a first preliminary assessment carried out by the Bundeskartellamt in late 2011, revenue from the supply of drinking water in Mainz appeared to be excessive. During the course of the investigations it became clear that the higher costs were partially due to special structural features of the Mainz supply area. Due to its comprehensive survey of data from the 38 largest German water suppliers, carried out in the course of its abuse control proceedings against the water supplier Berliner Wasserbetriebe, the Bundeskartellamt was in an excellent position to compare and assess the revenue and costs of Stadtwerke Mainz.

The price reduction only covers the price elements on which the company has an influence, i.e. charges excluding taxes and duties, as the latter are generally set and collected by the state on the basis of laws or ordinances. The Land of Rhineland-Palatinate plans to introduce a groundwater extraction rate of 0.06 €/m³ as of 1.1.2013. The price reduction for water customers in Mainz could thus lose some of its effect.

A public version of the Bundeskartellamt's commitment decision (in German) will shortly be available on the authority's website.