StopUP - Protecting the aquatic environment from urban runoff pollution



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  plan of of urban diffuse pollution Copyright: © ISA

In urban areas, a wide variety of pollutants is generated through anthropogenic activities and contaminates municipal and industrial wastewater as well as urban surface runoff during rain events. Since wastewater treatment plants do not have the capacity to treat the occurring wastewater especially during strong storm events, combined sewer overflow releases the untreated wastewater directly into the aquatic environment. In case of a separated sewer system, the collected rainwater is also introduced directly into the nearest water body and poses a further pollutant source for the aquatic environment.

The project StopUP deals with the characterization of urban runoff pollution to adequately adapt technical solutions for pollutant retention in order to protect the aquatic environment. Such solutions need to consider case-specific contexts including geography, climate, land use and receiving waters. StopUP aims to fill this need and proposes to provide new methods, information, tools and guidance on how to more effectively limit the impact of urban diffuse pollution.

In addition to the coordination of the overall project, ISA develops a process to reduce the needed area of retention soil filters (RSF) so that they can be integrated in urban areas with space limitations. First, lab experiments are conducted to find out optimal hydraulic conditions. Subsequently, a RSF pilot plant connected to the rain overflow basin will be developed and operated. An additional monitoring of the brand new full-scale RSF at the wastewater treatment plant Aachen-Soers (filter area of about 14600 m²) shall investigate the reduction of pollutant emission into the sensible river “Wurm”.

In total, 11 partners (9 beneficiaries, 2 associates) from 8 countries (Germany, Belgium, Netherlands, Norway, Italy, Switzerland, Great Britain, Tunesia) participate within the research project. The European Union is funding StopUP for 3 years as part of the research and innovation program Horizon Europe with 3,7 million euros.

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Information about Research Project StopUP

Funding Agency

European Union (EU)


September 2022 to September 2025

Project Manager

Dr. rer. nat. Simone Lechthaler
Leonie Wacker, M. Sc.
Jan-Lukas Wolber, M.Sc.

Project Partner

Aquafin NV
Norwegian University of Science and Technology (NTNU)
ATD Ingenieurgesellschaft für Abwasserwirtschaft und technische Dienstleistungen mbH
University of Bologna (UNIBO), FLUVES BV
HR Wallingford Ltd, TAUW BV, Aqua Aurora BV
Fachhochschule Nordwestschweiz (FHNW)
Institut Superiéur des Sciences Biologiques Appliquées de Tunis (ISSBAT)