Bad Homburg / Ober-Eschbach sewage treatment plant

Our task is to treat the up to 62400m³ of wastewater and rainwater produced daily by the town of Bad Homburg and the Oberursel Oberstedten district.

As the wastewater does not flow to the treatment plant on its own, we also monitor and manage 7 rainwater overflow basins and 5 pumping stations. The wastewater treatment plant performs mechanical-biological-chemical treatment of wastewater with a population equivalent of up to 80,000. Our aim is not only to achieve the minimum purification performance required by law, but also to achieve the highest possible purification performance, taking into account economic efficiency, so that water pollution remains low.

Bad Homburg is getting a new wastewater treatment plant! The current wastewater treatment plant is no longer able to cope with future tasks and population levels and will be replaced by a modern and advanced one. This mammoth project is scheduled to take around six years.

Briefly explained: How a wastewater treatment plant works

More than 6.5 million cubic meters of water are treated at the Bad Homburg wastewater treatment plant every year. Turning on the tap or flushing the toilet are everyday processes for us. But what happens afterwards?

• In the sewage treatment plant, the wastewater first flows into a waterway where it passes through the screen. This filters out coarse waste such as food scraps. Then comes the sand and grease trap, where smaller residues such as peas, corn or even sand and grease are filtered out over a distance of 25 meters.
• This is followed by primary clarification. Here, the water flows vertically through a basin in which organic components settle and are pumped into so-called digestion tanks. After this process, mechanical clarification is complete and the water is freed from the coarsest impurities.
• The next step is biological purification: Microorganisms absorb components of the wastewater into their metabolism and thus purify it naturally. This includes the addition of large quantities of oxygen and the conversion of ammonium to elemental nitrogen.
• The third stage involves chemical purification. The residues that could not be "eaten" by the microorganisms are eliminated here using aluminum hydroxychloride. The water then flows through the underground secondary clarifier and finally into the Eschbach in process water quality.