Department Urban Water Management

The project “Blue Green Fate” aims to improve the understanding of the fate of organic contaminants (biocides, industrial chemicals, tire wear leachates) in blue-green infrastructures (BGIs). Urban stormwater runoff carries a complex mixture of organic chemicals that can threaten groundwater and surface water quality. While BGI systems are increasingly implemented to manage stormwater, their effectiveness in removing organic chemicals, particularly emerging compounds, such as tire-derived chemicals, remains poorly understood. In addition, extreme weather events may significantly influence contaminant transport and retention processes, yet their effects remain largely uncertain. Therefore, this project investigates the transport dynamics of selected organic chemicals in BGIs and how they are altered under extreme weather conditions.

The project consists of three parts:

1. The fate of organic contaminants in pilot-scale biofilters: Processes affecting the fate of emerging organic stormwater contaminants are investigated under controlled conditions using pilot-scale column experiments and subsequent modeling of these processes. In addition to biocides and industrial stormwater chemicals, this part includes the leaching of organic chemicals from tire-wear particles (TWPs).
2. Extreme weather effects on pilot-scale biofilter: The effect of extreme weather conditions, such as heavy rainfall or prolonged dry periods, on the fate of emerging organic contaminants (incl. biocides, industrial chemicals, TWP leachates) is examined using pilot-scale column experiments and modelling.
3. Transferability to field-scale biofilters: An existing biofilter system is monitored and modelled to evaluate findings from pilot-scale biofilters to real-world conditions.

The findings of this project will support the development of evidence-based stormwater management strategies that protect groundwater and surface water resources, which are essential for ecosystem integrity and human health.