The Urselbach rises below the Großer Feldberg in the Hochtaunus and flows into the Nidda near Heddenheim. The idyllic river is a popular hiking destination because of the remaining mills and water wheels, and yet its biological balance, like that of all water bodies, must be constantly controlled. According to official measurements, almost 3,000 kilogrammes of dissolved phosphorus entered the Urselbach in 2016 alone. The high level of phosphorus in the water bodies leads to increased growth of algae and aquatic plants and decreases the oxygen content in the water. Improving water quality has therefore been on the political agenda for many years.
Flocculation-filtration plant removes phosphorus and solids from wastewater
In order to meet the increasingly strict environmental regulations in the future, the Oberursel wastewater treatment plant has been implementing a step-by-step plan for phosphorus elimination for several years. The goal is to reduce the values in the final stage to a daily average of no more than 0.2 milligrams per litre. After a state-of-the-art precipitant station opened in 2020, where most of the phosphorus compounds are precipitated out of the wastewater, a flocculation-filtration plant will be built on the site by the end of 2023. It will further reduce the phosphate and solids content of the wastewater before it is discharged into the Urselbach.