Wasserwerke Westfalen GmbH (WWW) has completed the installation of advanced treatment systems at its five water treatment plants. The final step was the commissioning of the system at the Halingen water treatment plant. As a result, all facilities now feature additional technical processing stages that go beyond traditional, nature-based drinking water treatment.

The starting point for the expansion was the precautionary principle: The existing drinking water treatment processes were to be supplemented with technologies capable of addressing contaminants that are currently unknown or may emerge in the future. The first “advanced treatment plant” (WAA) was commissioned ten years ago at the Echthausen water treatment plant. Since then, the other facilities have been gradually retrofitted.

“With the commissioning of the Halingen water treatment plant, we have successfully completed our modernization marathon. Now, five state-of-the-art water treatment plants ensure the supply of drinking water as part of the network with Gelsenwasser and DEW21,” said WWW Managing Director Bernd Heinz.

160 million euros for additional process engineering

Wasserwerke Westfalen, together with its shareholders DEW21 and Gelsenwasser, invested a total of 160 million euros in the expansion of its water treatment facilities. Approximately 40 million euros of that amount went to the Halingen water treatment plant.

The investment focused on additional treatment stages designed to specifically remove or reduce various groups of substances. These include, among others, organic trace substances, persistent compounds, and microbiological contamination.

“Drinking water is our most important food source, and together we are taking responsibility for protecting it. This investment ensures that we are prepared for microbiological or chemical contaminants that are not yet known but may emerge in the future,” explains Peter Flosbach, CEO of DEW21.

Combination of Various Treatment Methods

The expanded treatment plants combine several physical, chemical, and biological processes. The processes used include ozonation, flocculation, multilayer filtration, and adsorption on granular activated carbon.

In ozonation, ozone is used to oxidize iron and manganese dissolved in water. At the same time, persistent organic compounds are broken down, making them easier to remove afterward.

In the subsequent flocculation process, finely dispersed substances are aggregated into larger particles by adding a flocculant. These so-called flocs can be separated more efficiently in the subsequent filtration stages.

Multilayer filtration is carried out using biologically active layers of anthracite coal and quartz sand. This process removes turbidity and particles, while also reducing bacteria and organic and inorganic compounds.

Another stage of purification involves adsorption on granular activated carbon. This binds organic substances that are difficult to biodegrade and removes, for example, pesticide residues or pharmaceutical residues from the water.

Switch to chemical-free finishing

The post-treatment process for water treatment has also been modified. Instead of the previous chemical deacidification using caustic soda, WWW will use a physical process in the future.

During this process, the water is infused with fine air bubbles. The carbon dioxide it contains is released, causing the water’s pH level to change until it reaches the calcium-carbonate equilibrium.

In addition, the disinfection process at the Halingen water treatment plant has been converted to UV technology. Exposure to UV light inactivates any remaining microorganisms without the addition of chemical disinfectants. This eliminates the need for the chlorine dioxide that was previously used.

Infrastructure project with a long-term outlook

The expansion of the facilities implements the requirements of the “Reine Ruhr” program of the North Rhine-Westphalia Ministry of the Environment. The goal is to maintain a consistently high standard of quality in drinking water treatment.

“The Ruhr River is the most important source of drinking water in North Rhine-Westphalia. By implementing this expanded treatment process, we are ensuring drinking water quality for the next generation. I am pleased that this major, complex investment was carried out within the planned budget,” says Gelsenwasser Executive Board Member Dr. Dirk Waider.

The modernization coincides with the 25th anniversary of Wasserwerke Westfalen GmbH. When the company was founded in 2001, the plan was to consolidate the eight water treatment plants that existed at the time into five locations and to leverage synergies in partnership with DEW21 and Gelsenwasser.

“With the merger of the DEW21 and Gelsenwasser water utilities in 2001, we were able to consolidate our operations across locations and thus implement the new treatment plants within the network in a way that optimized costs, expertise, and processes—a true success story,” says WWW Managing Director Friederike Konold-Rüsel, reflecting on the company’s early days.

With the completion of the work, the association now has five modernized water treatment plants that combine traditional, nature-based treatment with additional technical purification stages.