title: Developing an easy-to-apply model for identifying relevant pathogen pathways into surface waters used for recreational purposes.
abstract: Swimming in inner-city surface waters is popular in the warm season, but can have negative consequences such as gastro-intestinal, ear and skin infections. The pathogens causing these infections commonly enter surface waters via several point source discharges such as the effluents from wastewater treatment plants and sewer overflows, as well as through diffuse non-point sources such as surface runoff. Nonetheless, the recreational use of surface waters is attractive for residents. In order to save financial and organizational resources, local authorities need to estimate the most relevant pathways of pathogens into surface waters. In particular, when detailed data on a local scale are missing, this is quite difficult to achieve. For this reason, we have developed an easy-to-apply model using the example of Escherichia coli and intestinal enterococci as a first approach to the local situation, where missing data can be replaced by data from literature. The model was developed based on a case study of a river arm monitored in western Germany and will be generalized for future applications. Although the limits of the EU Bathing Water Directive are already fulfilled during dry weather days, we showed that the effluent of wastewater treatment plants and overland flow had the most relevant impact on the microbial surface water quality. On rainy weather days, combined sewer overflows are responsible for the highest microbial pollution loads. The results obtained in this study can help decision makers to focus on reducing the relevant pathogen sources within a catchment area.
authors.affiliation: Institute of Environmental Engineering of RWTH Aachen University (ISA), Mies-van-der-Rohe-Str. 1, 52074 Aachen, Germany. Electronic address: tondera@isa.rwth-aachen.de.
authors.forename: Katharina
authors.initials: K
authors.lastname: Tondera
authors.affiliation: Institute of Environmental Engineering of RWTH Aachen University (ISA), Mies-van-der-Rohe-Str. 1, 52074 Aachen, Germany.
authors.forename: Kassandra
authors.initials: K
authors.lastname: Klaer
authors.affiliation: Institute of Environmental Engineering of RWTH Aachen University (ISA), Mies-van-der-Rohe-Str. 1, 52074 Aachen, Germany.
authors.forename: Silke
authors.initials: S
authors.lastname: Roder
authors.affiliation: Institute of Environmental Engineering of RWTH Aachen University (ISA), Mies-van-der-Rohe-Str. 1, 52074 Aachen, Germany.
authors.forename: Ira
authors.initials: I
authors.lastname: Brueckner
authors.affiliation: IWW Rheinisch-Westfaelisches Institut fuer Wasser, Moritzstr. 26, 45476 Mülheim an der Ruhr, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Strathmann
authors.affiliation: Institute for Hygiene and Public Health (IHPH), University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kistemann
authors.affiliation: Institute for Hygiene and Public Health (IHPH), University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany.
authors.forename: Christiane
authors.initials: C
authors.lastname: Schreiber
authors.affiliation: Institute of Environmental Engineering of RWTH Aachen University (ISA), Mies-van-der-Rohe-Str. 1, 52074 Aachen, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Pinnekamp
mesh_terms: D016983:Enterococcus / Q000302:isolation & purification; D004784:Environmental Monitoring; D004926:Escherichia coli / Q000302:isolation & purification; D005858:Germany; D008962:Models, Theoretical; D011891:Rain; D011998:Recreation; D045483:Rivers / Q000382:microbiology*; D014865:Waste Disposal, Fluid; D014871:Water Microbiology; D014873:Water Pollutants / Q000302:isolation & purification; D060753:Water Quality
chemical_list: D014873:Water Pollutants
keywords: Bathing water Directive; Combined sewer overflow; Diffuse sources; Modelling pathways; Pathogens; Point sources; Waterborne diseases