As part of the Engineered Natural Treatment Systems (ENTS) course taught by Benedikt Aumeier, we visited the Irschenberg wastewater treatment plant on Wednesday 12.12.2025. There is a lot going on there right now: the plant is being expanded from 5,000 to 7,000 PE and is being equipped with a stage for the removal of trace organic chemicals (TOrCs) – implemented as an innovative vertical filter Biofiltrationplus.
What’s behind the Biofiltrationplus? A system that not only reliably removes micropollutants, but also serves as a buffer for the effluent. The filter combines sand (biological degradation of TOrCs) and granular activated carbon (adsorption). This protects the sensitive receiving water from TOrCs loads and effectively intercepts discharge peaks.
Mr. Schmidt, the plant manager, guided us from the inlet to the outlet through the construction site, sharing valuable technical insights along the way. The main focus of the filed trip was the new Biofiltrationplus, whose planning our chair has supported as part of a doctoral research project (Anna-Sonia Kau, Dr. Benedikt Aumeier, Prof. Jörg E. Drewes). We will also be responsible for operational support for the filter after it goes into operation in May 2026. The Biofiltrationplus will be one of the first plants for TOrCs removal in Bavaria. The project is funded by the Bavarian Ministry of the Environment, Urban Development and Energy (StMUV) and is intended to serve as a blueprint for many other small wastewater treatment plants. You can find out more about the project here.
A clear highlight for the students was the already fully filled filter – they were visibly impressed to experience such an innovative engineered natural treatment system in practice.
Many thanks to Mr. Schmidt for his great support during the excursion!