The contaminant transport of hydrophobic pollutants is often facilitated by the transport of suspended sediments. For example, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), pharmaceuticals, heavy metals and faecal microorganisms are attached to particles that can be mobilised during heavy rainfall events. This affects surface water quality and creates public and ecosystem health risks.
Quantification and characterisation of diffuse pollution sources and particle bound pollutants remain a challenge. European governments continue facing problems in order to implement the European Union’s Water Framework Directive (WFD), especially while tackling diffuse pollution from urban areas and maintaining healthy ecosystems. Despite high investments, the implemented management alternatives are still inefficient. Hence, this project mainly aims to understand the impact of the fate and transport of particle bound contaminants on the water quality of urbanised catchments. This will allow development of an innovative approach for selecting appropriate technology and strategies to achieve good water quality status of water bodies receiving urban emissions.
I will focus primarily on particle bound pollutants related to urban diffuse and point discharges into surface water bodies. In order to improve urban water management, I will address the following objectives:
• Understand the relationship between drivers of relevant particle bound contaminants (i.e. heavy metals, pharmaceuticals, PAH) and response of the urban water system under dynamic conditions (i.e. variable sediment load, precipitation, storm water discharge, river flow, combined sewer overflow - CSO and discharge from waste water treatment plants - WWTP).
• Characterise the main processes that affect relevant dissolved and particle bound contaminant and sediment transport (adsorption, desorption, sedimentation, re-suspension) and their impact on the spatiotemporal variability of the contaminants.
• Identify the sources of sediments, the attached relevant particle bound contaminants and their relative contribution to a given study area (e.g. Lockwitzbach catchment, Holtemme river).
• Evaluate the impact of the relevant particle bound contaminants on the water quality of rivers under different flow regimes considering seasonal variations.
• Develop a framework to propose appropriate urban water management strategies to reduce and control diffuse pollution and especially particle bound contaminants for a given study area considering relevant water quality standards.
Within a framework of complex water-related interactions among people, urban drainage systems, and rivers, overall goal of this project is to characterise the transport process of particle bound pollutants coming from urban environments. I will evaluate water quality and quantity using high-resolution observed data obtained by novel measurement techniques. The data come from two urban observatories in Germany: one in Dresden, and one planned in Wernigerode by the UFZ. Such monitoring stations will include observation points in the sewers and the receiving water bodies. The analysis of water quality impacts will be done based on modelling and statistical approaches. Therefore, my project will not only provide a better understanding of transport of particle bound contaminants but, also it is expected to facilitate the implementation of an effective integrated water management, which considers the interaction between urban water drainage networks and aquatic ecosystems.