D1.3: Library (inventory) of pollutants from urban runoff

1 D1.3: Library (inventory) of pollutants from urban runoff June 2025 Anders R. Johnsen (GEUS) Cecilie I. K. Hansen (GEUS) Thomas M. M. Karlsson (UCPH) Jan H. Christensen (UCPH) Ulla E. Bollmann (GEUS) Data driven implementation of hybrid nature-based solutions for preventing and managing diffuse pollution from urban water runoff Ref. Ares(2025)4705954 - 12/06/2025 2 D1.3 Deliverable title Work Package WP1 Deliverable lead Geological Survey of Greenland and Denmark (GEUS) Author(s) Anders R. Johnsen (GEUS) Cecilie I. K. Hansen (GEUS) Thomas M. M. Karlsson (UCPH) Jan H. Christensen (UCPH) Ulla E. Bollmann (GEUS) Contact [email protected] Grant Agreement number 101060638 Start date of the project / Duration 1 September 2022 / 42 months Type of deliverable (R, DEM, DEC, other) R Dissemination level (PU, SEN) PU Project website www.d4runoff.eu R=Document, report; DEM=Demonstrator, pilot, prototype; DEC=website, patent fillings, videos, etc.; OTHER=other PU=Public, SEN=Sensitive, limited under the conditions of the GA Document history Version Date Authors (organisation) 0.10 19.04.2024 Anders R. Johnsen (GEUS), Cecilie I. K. Hansen (GEUS), Ulla E. Bollmann (GEUS). 0.11 28.04.2024 Revision by Jan H. Christensen (UCPH) and Thomas M. M. Karlsson (UCPH). 1.0 30.04.2024 Submitted version, with preliminary inventory data. 2.0 03.06.2025 Anders R. Johnsen (GEUS). Revision according to PO comments, updated with final inventory data. 3 ACKNOWLEDGEMENTS This project has received funding from the European Union’s Horizon Europe research and innovation programme under grant agreement No 101060638. COPYRIGHT STATEMENT The work described in this document has been conducted within the D4RUNOFF project. This document reflects only the D4RUNOFF Consortium views, and the European Union is not responsible for any use that may be made of the information it contains. This document and its content are the property of the D4RUNOFF Consortium. All rights relevant to this document are determined by the applicable laws. Access to this document does not grant any right or license on the document or its contents. This document or its contents are not to be used or treated in any manner inconsistent with the rights or interests of the D4RUNOFF Consortium or the Partners detriment and are not to be disclosed externally without prior written consent from the D4RUNOFF Partners. Each D4RUNOFF Partner may use this document in conformity with the D4RUNOFF Consortium Grant Agreement provisions. 4 Executive Summary The overall aim was to answer the questions: 1. Which pollutants are present in European stormwater and at which concentration levels? and 2. Are there major differences between mixed stormwater and local stormwater sources? The last question is especially important as most previous stormwater studies have analyzed mixed urban stormwater collected from large areas, but the stormwater to be handled in nature-based solutions (NBS) is often of very local origin such as in street rain beds and infiltration ponds in residential areas. Stormwater was sampled from stations at five sites across Europe: Odense (Denmark), Copenhagen (Denmark), Santander (Spain), Pontedera (Italy), and Ljubljana (Slovenia). For consistent sampling by different project partners and external partners, it was necessary first to develop protocols for stormwater sampling and station characterization and to provide standardized ready-to-use samplingand shipping kits. Methods were developed for quantification of microbial antibiotic resistance, and quantificationand suspect screening for pollutants of emerging concern in source stormwater. The analytical results for water characterization and pollutants are available as an inventory data file (excel-file). Antibiotic resistance genes in source stormwater were quantified by droplet digital PCR (ddPCR). This method was supported by petrifilm-counts of cultivable antibiotic-resistant Enterobacterales, an order that covers a range of pathogenic or opportunistic pathogenic gut bacteria. The highest antibiotic resistance levels were found in combined sewer overflow and wastewater treatment plant bypass. This is not surprising, as both stormwater types are surface runoff mixed with domestic sewage. It was more surprising that we also found some antibiotic resistance in stormwater from streets and residential areas. These samples presumably were only surface runoff from streets and roofs with no wastewater, but counts of fecal E. coli suggest that that there was indeed some degree of fecal contamination, probably from misconnected sewer pipes and possibly also from dog feces and bird droppings. Overall, the highest variation was seen for sulfonamide resistance genes that were detected in almost all samples and varied more than five orders of magnitude. Organic micropollutants in source stormwater were analyzed with reversed-phase liquid highresolution mass spectrometry (RP-LC-HRMS) and hydrophilic interaction liquid highresolution mass spectrometry (HILIC-HRMS) to cover a wide range of compound mobilities. RP-LC-HRMS was applied for full quantification of selected compounds and for suspect screening. HILIC-HRMS was applied only for suspect screening. Suspect screening is searching for compounds in the HRMS-data based only on mass spectra and retention times (i.e. no standards) by comparison to a list of predefined suspect pollutants. The target analyses of runoff samples showed the presence of pollutants that indicate specific pollution sources such as domestic sewage and rubber from the wear of tires. Suspect screening furthermore indicated the occurrence of various quaternary ammonium compounds and a wide range of additional suspect compounds. To conclude: there were large differences between the different types of storm water. There was especially a split between stations with an input of domestic sewage and stations only with various kinds of surface runoff. The local differences in pollutant composition should be considered when designing nature-based solutions for local handling urban stormwater. 5 1 Table of Contents 1 Table of Contents ......................................................................................................... 5 2 Introduction .................................................................................................................. 8 2.1 Purpose of the document ....................................................................................... 8 2.1.1 Scope of the document ...................................................................................... 8 2.1.2 Structure of the document .................................................................................. 8 3 Origin of urban stormwater pollutants - literature overview. .................................... 9 4 Stormwater sampling and stations ............................................................................10 5 Analysis of stormwater samples ................................................................................15 5.1 General characterization of stormwater samples...................................................15 5.1.1 Precipitation ......................................................................................................15 5.1.2 Turbidity, pH, conductivity .................................................................................15 5.1.3 DOC and TOC ..................................................................................................16 5.1.4 Anions and cations ............................................................................................17 5.1.5 Trace elements .................................................................................................18 5.2 Microbial indicators of fecal contamination and antibiotic resistance .....................21 5.2.1 Fecal contamination ..........................................................................................21 5.2.2 Quantification of cultivable, antibiotic resistant Enterobacterales using petrifilms 23 5.2.3 Quantification of antibiotic resistance genes by digital droplet PCR ..................27 5.3 Organic micropollutants ........................................................................................29 5.3.1 Target and suspect screening analysis with RP-LC-HRMS ...............................29 5.3.2 RP-LC-HRMS results ........................................................................................30 5.3.3 Suspect screening using HILIC-HRMS ..............................................................31 5.3.4 Accumulation of organic micropollutants during dry periods. .............................32 6 Overall discussion ......................................................................................................34 7 References ...................................................................................................................36 Annex A. Potential stormwater pollutants identified in reports from the Danish Environmental Protection Agency ....................................................................................40 Annex B. Protocol for sampling, shipping, and subsampling of urban stormwater .....44 Annex C. Antibiotics sales statistics ................................................................................46 Annex D. Descriptions of sampled stations .....................................................................47 6 List of Tables Table 1. Overview of cities and stations. ..............................................................................12 Table 2. Acid-soluble trace elements in stormwater. .............................................................19 Table 3. Antibiotics concentrations used in the petrifilms and agar plates. ...........................24 Table 4. Targets of ddPCR quantification of resistance genes in stormwater. ......................28 List of Figures Figure 1. Geographical overview of stations with indication of sampled stormwater types. ...11 Figure 2. Sample kit for one station. .....................................................................................13 Figure 3. Temperature profile for a subsample in a full sample kit incubated at room temperature (20-22 °C). Temperature profile for a subsample in a full sample kit incubated at room temperature (20-22 °C)................................................................................................14 Figure 4. Changes in conductivity and turbidity during rain events. Co02 Rigensgade: roof and street runoff (5.0 mm) from central Copenhagen after 34 dry days, Co10 Øster Voldgade: roof runoff (7.5 mm) from central Copenhagen after 1 dry day. ...........................15 Figure 5. Variation during first flush at a street rain bed (Od03, Kallerupvej) where the previous rain event was the day before. ...............................................................................16 Figure 6. Dissolved organic carbon (DOC) in stormwater from the cities Copenhagen (Co, Denmark), Ljubljana (Lj, Slovenia), Odense (Od, Denmark), Pontedera (Po, Italy), Riga (Ri, Latvia), and Santander (Sa, Spain). .....................................................................................16 Figure 7. Dissolved organic carbon concentration versus the number of dry days before sampling. Only stations without combined sewer overflow and artificial football fields. .........17 Figure 8. Dissolved organic carbon concentration versus the precipitation during sampling. Only stations without combined sewer overflow and artificial football fields. .........................17 Figure 9. Dissolved ammonium in stormwater from the cities Copenhagen (Co, Denmark), Ljubljana (Lj, Slovenia), Odense (Od, Denmark), Pontedera (Po, Italy), Riga (Ri, Latvia), and Santander (Sa, Spain). .........................................................................................................18 Figure 10. Dissolved chloride in stormwater from the cities Copenhagen (Co, Denmark), Ljubljana (Lj, Slovenia), Odense (Od, Denmark), Pontedera (Po, Italy,) Riga (Ri, Latvia), and Santander (Sa, Spain). .........................................................................................................18 Figure 11. Acid-soluble lead (Pb), cadmium (Cd), mercury (Hg), and Nickel (Ni) in stormwater from the cities Copenhagen (Co, Denmark), Ljubljana (Lj, Slovenia), Odense (Od, Denmark), Riga (Ri, Latvia), and Santander (Sa, Spain). Red lines indicate environmental quality standards for inland surface waters and other surface waters according to EU directive 2008/105/EC. .......................................................................................................................20 Figure 12. Subsamples of the sampling at the Po05 station with high concentrations of trace metals. .................................................................................................................................21 Figure 13. E. coli/coliform petrifilms showing E. coli with characteristic gas bubbles (lactose fermentation) and blue color (glucuronidase-positive). Left: station Co01, right station Od01. .............................................................................................................................................22 7 Figure 14. Quantification of E. coli in stormwater from the cities Copenhagen (Co, Denmark), Ljubljana (Lj, Slovenia), Odense (Od, Denmark), Pontedera (Po, Italy, Riga (Ri), Latvia)),and Santander (Sa, Spain). CFU: colony-forming units. ..............................................................22 Figure 15. Streets and rain beds often had dog feces in different degrees of disintegration. Left: Od02 – Hørdumsgade; right: Od03 – Kallerupvej. ........................................................23 Figure 16. Inoculation of petrifilm with stormwater (left) and petrifilm with ciprofloxacinresistant Enterobacterales bacteria (the gas producers) from Po01 stormwater containing sewer overflow at (right). ......................................................................................................25 Figure 17. Prevalence of cultivable tetracycline-resistant Enterobacterales in stormwater from the cities Copenhagen (Co, Denmark), Ljubljana (Lj, Slovenia), Odense (Od, Denmark), Pontedera (Po, Italy,) Riga (Ri, Latvia), and Santander (Sa, Spain). CFU: colony-forming units. ....................................................................................................................................26 Figure 18. Confirmation or antibiotic resistance in petrifilm isolates streaked on MuellerHinton-natamycin agar with tetracycline (Tc), amoxicillin (Amx), trimethoprim (Trp) or ciprofloxacin (Cpf). ...............................................................................................................26 Figure 19. ddPCR detection of Sul1 genes in four stormwater samples including positive controls and reagent blanks. Blue dots represent nanodrops with a positive PCR-signal. Grey dots are PCR-negative nanodrops. ......................................................................................27 Figure 20. Quantification of tetB tetracycline resistance genes in stormwater from the cities Copenhagen (Co, Denmark), Ljubljana (Lj, Slovenia), Odense (Od, Denmark), Pontedera (Po, Italy) and Santander (Sa, Spain). ..................................................................................28 Figure 21. Heatmap of detected target analytes quantified with RP-LC-HRMS, scaled to maximum concentration for each analyte. Yellow and green color indicates high versus low relative abundance respectively. ..........................................................................................30 Figure 23. Occurrence of myristamine oxide in stormwater samples; peak intensity was normalized to the internal standard atrazine-desisopropyl-D5. .............................................32 Figure 24. Algicide for sale at a Danish supermarket. The active substance is the quaternary ammonium compound didecyldimethylammoniumchloride (0,5% w/w). The product is intended for removing algae from: “hard surfaces such as cement, fiber-cement, concrete, terracotta, wood, glass, metal, plastic, solar panels, brick, roofs, facades, wooden terraces, garden furniture, fences and so on. For annual maintenance”. .............................................32 Figure 25. Concentration of selected micropollutants versus the number of dry days before sampling. Only stations with street runoff. ............................................................................33 8 2 Introduction 2.1 Purpose of the document This deliverable (1.3 “Library of pollutants from urban runoff in Nature Based Solutions”) represents work carried out in the Horizon Europe project “Data driven implementation of hybrid nature-based solutions for preventing and managing diffuse pollution from urban water runoff – D4RUNOFF”, work package 1 “Novel detection methods for urban runoffs pollutants characterization”, task 1.3 “Screening for CECs, pathogenic indicators, and microbial resistance in urban runoff”. 2.1.1 Scope of the document The purpose of the deliverable is to document the methodologicaland analytical approaches for sampling urban stormwater and for quantification of pollutants and other parameters reported in the inventory to aid users of the inventory with respect to data interpretation. The report and the associated inventory data-file therefore presents detailed data on different types of urban stormwater origins such as inner-city street runoff, highway runoff, roofand façade runoff, artificial football field drainage, overflow from combined sewers, by-pass of mixed stormwater at wastewater treatment plants etc. The inventory data-file covers identified pollutants in stormwater samples from the project’s case studies together with stormwater samples from across Europe. The inventory data-file has the following main data categories: Basic characterization: Conductivity, turbidity, pH, dissolved organic carbon (DOC) and total organic carbon (TOC) analysed by GEUS. Inorganic components: Anions and cations analysed by GEUS; trace elements analysed by Eurofins Denmark. Microbial indicators: E. coli, cultivable antibiotic resistant Enterobacterales, antibiotic resistance genes, and integron integrase genes (mobile genetic elements) quantified by GEUS. Organic micropollutants: Targetand suspect screening using reversed-phase liquid chromatography high-resolution mass spectrometry (RP-LC-HRMS) was done by UCPH. Suspect screening using hydrophilic interaction chromatography high-resolution mass spectrometry (HILIC-HRMS) was done by GEUS. 2.1.2 Structure of the document Together with the inventory file (Inventory_source stormwater_D4RUNOFF_version 203.xlsx), this report constitutes deliverable 1.3. The inventory file and the report cover identified pollutants in stormwater samples from the project’s case studies together with stormwater samples from across Europe. The inventory gives data on pollutants in urban stormwater of different origins such as inner-city street runoff, roofand façade runoff, artificial football field drainage, highway runoff, overflow from combined sewers, by-pass of mixed stormwater at wastewater treatment plants etc. The inventory file is formatted so that it can be imported in common databases such as Microsoft Access and used in work package 4 “AI-Assisted urban runoff management platform”. The submitted deliverable was as a draft version of the inventory data covering only the first 21 stations. The present, revised deliverable (version 2.0) covers data from all 38 stations. Thorough descriptions or each station are included in Annex D to support the analytical data. The inventory data will be published and discussed in scientific articles covering: 1) Antibiotic resistance in urban stormwater, and 2) Organic micropollutants in urban stormwater. 9 3 Origin of urban stormwater pollutants - literature overview. The origin of pollutants can be viewed at several levels. The immediate source relates to the type of urban stormwater, this is the subject of the following report chapters. The sources may, however, also be seen as the sources within the urban environment that releases specific pollutants. Sources are evident for many of the potential stormwater pollutants. Pesticides and their transformation products are used in agriculture and to some extend in private gardens and public areas such as squares, streets, and parks. Pharmaceuticals and their transformation products in the urban environment probably originate mainly from domestic sewage that contaminates stormwater by sewer bypass, sewer overflow, pipe leakage etc. Aliphatic hydrocarbons and alkylated low-molecular-weight aromatics originate mainly from petrole-um products, non-alkylated polycyclic aromatic compounds (PACs) originate mainly from combustion processes in traffic and domestic heating. Rubber chemicals come from the wear of car tires, etc. Sources for other contaminants are less obvious. In this overview, we have assembled data from technical reports to aid the method development and the interpretation of the inventory data. The cited references are non-English technical reports that often do not show up in searches of the scientific literature. The identified pollutants and their sources are listed in Annex A. The following sources were reviewed: • Biocides leached from building materials (Bester, 2022). • Organic compounds and inorganics leached from crushed concrete, brick, and roof tile (Hjelmar et al., 2018). • Organic compounds and inorganics leached from surface-treated roof tile, concrete, and fiber-cement (Hjelmar et al., 2020). • Inventory of biocides used in Denmark up to 2000 (Lassen et al., 2001), only compounds judged relevant for the urban environment were added to Annex A. • Mapping and environmental assessment of cleaning agents for outdoor use (Peder-sen et al., 2023). • Particle-bound biocides (Vianello et al., 2021). For the organic micropollutants (e.g. industrial chemicals and biocides), we have added the compounds to HRMS suspect-screening lists together with runoff pollutants identified in the Danish project “Byer i Vandbalance” (Jensen et al., 2015) and scientific articles (Gasperi et al., 2022; Masoner et al., 2019; Zgheib, 2011; Peter et al., 2022; Eriksson et al., 2007; Page et al., 2014). . 16 Figure 5. Variation during first flush at a street rain bed (Od03, Kallerupvej) where the previous rain event was the day before. 5.1.3 DOC and TOC Dissolved organic carbon (DOC) and total organic carbon (TOC) were determined for all composite sample on a TOC-analyser (Shimadzu – Total Carbon analyzer – Vcph) after filtration through either a 0,45-µm QMAX PES filter (DOC) or through a 5-µm PVDF filter (TOC). Highest DOC-concentrations were found in samples with a long dry period before sampling (Figure 6, Od01 and Co02: 34 days, Co01: 17 days, Po02 and Po04: 12 days). This is more clearly seen when DOC is plotted against the number of dry days before sampling (R2=0,77; Figure 7) for stations without combined sewer overflow or infiltration through football fields. There was almost no correlation between DOC concentration and the amount of precipitation during sampling, showing that the amount of precipitation did not exert a simple dilution-of-first-flush effect (R2=0.17; Figure 8). Considering both dry period and the dilution by precipitation (DOC × precipitation versus dry period) decreased the correlation (R2=0.66; data not shown) compared to dry period alone. Figure 6. Dissolved organic carbon (DOC) in stormwater from the cities Copenhagen (Co, Denmark), Ljubljana (Lj, Slovenia), Odense (Od, Denmark), Pontedera (Po, Italy), Riga (Ri, Latvia), and Santander (Sa, Spain). 0 50 100 150 200 250 0 5 10 15 20 25 30 35 Turbidity [FTU] Time (min) Turbidity 6 6,25 6,5 6,75 7 7,25 7,5 7,75 8 0 5 10 15 20 25 30 35 pH Time (min) pH 0 20 40 60 80 100 120 140 160 0 5 10 15 20 25 30 35 Conductivity [µS/cm] Time (min) Conductivity 0,0 10,0 20,0 30,0 40,0 50,0 60,0 70,0 80,0 90,0 Co01 Co02 Co03 Co04 Co05 Co06 Co07 Co08 Co09 Co10 Co11 Co12 Lj01 Lj02 Lj03 Lj04 Lj05 Od01 Od02 Od03 Od04 Od05 Od06 Od07 Od08 Po01 Po02 Po03 Po04 Po05 Ri01 Ri02 Ri03 Sa01 Sa02 Sa03 Sa04 Sa05 Concentration (mg/L) DOC 17 Figure 7. Dissolved organic carbon concentration versus the number of dry days before sampling. Only stations without combined sewer overflow and artificial football fields. Figure 8. Dissolved organic carbon concentration versus the precipitation during sampling. Only stations without combined sewer overflow and artificial football fields. 5.1.4 Anions and cations The following soluble anions and cations were determined for the composite samples: F-, Cl-, Br-, NO3-, PO4--, SO4--, Na+, K+, Ca++, Mg++, and NH4+. Anions were determined by Metrohm 930 Compact IC Flex, Collum A supp. 5 – 150/4.0 after filtration through 0.45-µm filter. Soluble cations were determined by Metrohm 930 Compact IC Flex, Collum Metrosep. C6250/4.0 after filtration through 0.45-µm filter. Soluble ammonium was determined after filtration through 0.45-µm filter by a FIA Star 5000 analyzer – AN5220. Examples are shown in Figure 9 and Figure 10. Highest ammonium concentrations were found in samples containing sewage (Co12, Po01, Po02 and Sa05). Highest chloride concentrations were found in samples from a motorway retention pond (Lj02) probably from de-icing, and samples containing sewage (Co12, Po01 and Po02). y = 1,9126x -1,7972 R² = 0,7681 0 10 20 30 40 50 60 70 80 90 0 5 10 15 20 25 30 35 DOC (mg/L) Dry period (days) y = 2,9559x -2,2796 R² = 0,1749 0 10 20 30 40 50 60 70 80 90 0 3 6 9 12 15 DOC (mg/L) Precipitation during sampling (mm) 18 Figure 9. Dissolved ammonium in stormwater from the cities Copenhagen (Co, Denmark), Ljubljana (Lj, Slovenia), Odense (Od, Denmark), Pontedera (Po, Italy), Riga (Ri, Latvia), and Santander (Sa, Spain). Figure 10. Dissolved chloride in stormwater from the cities Copenhagen (Co, Denmark), Ljubljana (Lj, Slovenia), Odense (Od, Denmark), Pontedera (Po, Italy,) Riga (Ri, Latvia), and Santander (Sa, Spain). 5.1.5 Trace elements The stormwater samples were analyzed for the trace elements that are part of routine, commercial water analyses, plus vanadium that is an indicator for bitumen (e.g. El Beze et al., 2012). The samples were analyzed for acid-soluble trace elements by the accredited lab Eurofins Miljø A/S (Denmark). Eurofins provided 30-ml vials acidified with HNO3 according to the standard DS 259:2003. Eurofins analyzed the samples by ICP-MS according to the standard EN ISO 17294m:2016. The results are summarized in Table 2, and concentration are shown in Figure 11 for trace elements with environmental quality standards (EQS) for surface waters according to directive 2008/105/EC. Pb exceeded the EQS at 13 out of 38 stations with a maximum concentration of 51 μg/L. Highest concentrations were found in a roof runoff sample (Co10) followed by the street runoff sample (Po05). Cd exceeded the EQS at 6 out of 38 stations with a maximum concentration of 0.56 μg/L. Highest concentrations were found at a 0 10 20 30 40 50 Co01 Co02 Co03 Co04 Co05 Co06 Co07 Co08 Co09 Co10 Co11 Co12 Lj01 Lj02 Lj03 Lj04 Lj05 Od01 Od02 Od03 Od04 Od05 Od06 Od07 Od08 Po01 Po02 Po03 Po04 Po05 Ri01 Ri02 Ri03 Sa01 Sa02 Sa03 Sa04 Sa05 Concentration (mg/L) Ammonium 0 100 200 300 400 500 600 Co01 Co02 Co03 Co04 Co05 Co06 Co07 Co08 Co09 Co10 Co11 Co12 Lj01 Lj02 Lj03 Lj04 Lj05 Od01 Od02 Od03 Od04 Od05 Od06 Od07 Od08 Po01 Po02 Po03 Po04 Po05 Ri01 Ri02 Ri03 Sa01 Sa02 Sa03 Sa04 Sa05 Concentration (mg/L) Chloride 19 combined sewer overflow station (Po01) followed by a street runoff sample (Po05). Hg exceeded the EQS at 5 out of 38 stations with a maximum concentration of 0.14 μg/L. Highest concentrations were found at a combined sewer overflow station (Po01) and a street runoff sample (Po05). Ni exceeded the EQS at 3 out of 38 stations with a maximum concentration of 100 μg/L. By far the highest concentrations were found in a street runoff sample (Po05), the second highest concentration was from a street runoff sample (Po02). The road runoff sample from Po05 was high in almost all metals including 23,000 μg/L of Al suggesting prevalent metal contamination at this station. However, this sample also had a very high content of suspended material (Figure 12) and the highest turbidity of all samples (678 FTU), which may to some degree explain the high concentrations as trace metals are often associated with silt and clay particles. Po01, that was also high in many metals, had the second highest turbidity (597 FTU). Table 2. Acid-soluble trace elements in stormwater. Element Quantification limit, µg/L EQS*, µg/L No of samples No. of samples above threshold value Maximum concentration, µg/L Al, aluminium 30 - 38 - 23,000 Sb, antimony 1 - 38 - 18 As, arsenic 0.3 - 38 - 8,6 Pb, lead 0.5 7.2 38 13 51 B, boron 10 - 38 - 130 Cd, cadmium 0.05 0.2 38 6 0.56 Cr, chromium 0.5 - 38 - 110 Cu, copper 0.5 - 38 - 290 Co, cobalt 0.5 - 38 - 15 Hg, mercury 0.05 0.05 38 5 0.14 Ni, nickel 1 20 38 3 100 Se, selenium 1 - 38 - <1 V, vanadium 1 - 38 - 50 Zn, zinc 5 - 38 - 2600 *Environmental quality standards for inland surface waters and other surface waters according to EU directive 2008/105/EC. 0 10 20 30 40 50 60 Co01 Co02 Co03 Co04 Co05 Co06 Co07 Co08 Co09 Co10 Co11 Co12 Lj01 Lj02 Lj03 Lj04 Lj05 Od01 Od02 Od03 Od04 Od05 Od06 Od07 Od08 Po01 Po02 Po03 Po04 Po05 Ri01 Ri02 Ri03 Sa01 Sa02 Sa03 Sa04 Sa05 Concentration (µg/L) Pb µg/l 20 Figure 11. Acid-soluble lead (Pb), cadmium (Cd), mercury (Hg), and Nickel (Ni) in stormwater from the cities Copenhagen (Co, Denmark), Ljubljana (Lj, Slovenia), Odense (Od, Denmark), Riga (Ri, Latvia), and Santander (Sa, Spain). Red lines indicate environmental quality standards for inland surface waters and other surface waters according to EU directive 2008/105/EC. 0 0,1 0,2 0,3 0,4 0,5 0,6 Co01 Co02 Co03 Co04 Co05 Co06 Co07 Co08 Co09 Co10 Co11 Co12 Lj01 Lj02 Lj03 Lj04 Lj05 Od01 Od02 Od03 Od04 Od05 Od06 Od07 Od08 Po01 Po02 Po03 Po04 Po05 Ri01 Ri02 Ri03 Sa01 Sa02 Sa03 Sa04 Sa05 Concentration (µg/L) Cd µg/l 0 0,02 0,04 0,06 0,08 0,1 0,12 0,14 0,16 Co01 Co02 Co03 Co04 Co05 Co06 Co07 Co08 Co09 Co10 Co11 Co12 Lj01 Lj02 Lj03 Lj04 Lj05 Od01 Od02 Od03 Od04 Od05 Od06 Od07 Od08 Po01 Po02 Po03 Po04 Po05 Ri01 Ri02 Ri03 Sa01 Sa02 Sa03 Sa04 Sa05 Concentration (µg/L) Hg µg/l 0 20 40 60 80 100 Co01 Co02 Co03 Co04 Co05 Co06 Co07 Co08 Co09 Co10 Co11 Co12 Lj01 Lj02 Lj03 Lj04 Lj05 Od01 Od02 Od03 Od04 Od05 Od06 Od07 Od08 Po01 Po02 Po03 Po04 Po05 Ri01 Ri02 Ri03 Sa01 Sa02 Sa03 Sa04 Sa05 Concentration (µg/L) Ni µg/l 21 Figure 12. Subsamples of the sampling at the Po05 station with high concentrations of trace metals. 5.2 Microbial indicators of fecal contamination and antibiotic resistance Faecal contamination of water in the urban water cycle poses risks to the health of the urban populations if not managed properly. A first step in this risk management is to identify the sources of fecal contaminants and associated antibiotic resistances in the urban environment. In D4Runoff we have measured the levels of microbial resistance to antibiotics in urban stormwater and there are good reasons for this. According to the World Health Organization: “Antimicrobial resistance in infectious agents represents a global health security threat and continues to be a serious threat to human, animal and environmental health, as well as the well-being of the global economy” (WHO, 2022). Urban stormwater certainly is not the major exposure route for antibiotic resistant bacteria, but we suspected that some types of stormwater may be an overlooked reservoir of microbial antibiotic resistance. When designing nature-based solutions for handling stormwater, it is therefore important to know the levels and sources of antibiotics resistance, so that the solutions can be designed to reduce exposure to fecal and antibiotic-resistant bacteria. We have two approaches for measuring antibiotic resistance, one is based on classical growth of antibiotic-resistant bacteria on selective medium, the other is based on direct quantification of selected antibiotic resistance genes. The load of potentially pathogenic enterobacteria was quantified by developing a cultivation-based phenotypic method for screening water samples for the presence of Enterobacterales that were resistant to commonly used antibiotics. The load of antibiotic resistance genes in urban storm water was quantified by developing a digital droplet PCR (ddPCR) protocol from which it is possible to precisely quantify the copy-numbers of antibiotic resistance genes within different groups of bacteria. 5.2.1 Fecal contamination Fecal contamination was tested with standard test for the presence of E. coli. The test was based on serial dilution of the samples in 10 mM fosfate-buffer (pH =7.0) containing 22 natamycin to inhibit growth of fungi and yeasts. Natamycin was added as 2 ml/L of Delvocid (half natamycin, half lactose) suspended in water:methanol (1:1; 50 g/L). One-ml aliquots of the sample dilutions were added to coliform-selective petrifilms (3M Petrifilm E. coli/Coliform Count Plate) and the petrifilms were incubated at 44.5°C for 22-24 hours. To avoid desiccation, petrifilm stacks were wrapped in a plastic bag and placed in a sealed box with a wet paper towel to saturate the atmosphere with water. The number of colony-forming units (CFU) was determined from the number of blue colonies associated with gas bubbles (Figure 13) according to the manufacturer’s instructions. Colonies without gas bobbles were not counted. Figure 13. E. coli/coliform petrifilms showing E. coli with characteristic gas bubbles (lactose fermentation) and blue color (glucuronidase-positive). Left: station Co01, right station Od01. E. coli indicate fecal contamination and is generally applied as an indicator of wastewater pollution of the water environment. This was evident for the samples from combined sewer overflow and WWTP stormwater bypass (Figure 14). Some samples without obvious wastewater contamination also showed detectable E. coli. This was especially the suburban road runoff, probably contaminated with dog feces (Figure 15). Figure 14. Quantification of E. coli in stormwater from the cities Copenhagen (Co, Denmark), Ljubljana (Lj, Slovenia), Odense (Od, Denmark), Pontedera (Po, Italy, Riga (Ri), Latvia)),and Santander (Sa, Spain). CFU: colony-forming units. 1 10 100 1000 10000 100000 Co01 Co02 Co03 Co04 Co05 Co06 Co07 Co08 Co09 Co10 Co11 Co12 Lj01 Lj02 Lj03 Lj04 Lj05 Od01 Od02 Od03 Od04 Od05 Od06 Od07 Od08 Po01 Po02 Po03 Po04 Po05 Ri01 Ri02 Ri03 Sa01 Sa02 Sa03 Sa04 Sa05 CFU per mL E. coli 23 Figure 15. Streets and rain beds often had dog feces in different degrees of disintegration. Left: Od02 – Hørdumsgade; right: Od03 – Kallerupvej. 5.2.2 Quantification of cultivable, antibiotic resistant Enterobacterales using petrifilms As indicator organisms, we chose Enterobacterales which is a large family of Gram-negative gamma-proteobacteria that covers a range of pathogenic or opportunistic pathogenic gut bacteria as well as benign environmental bacteria. In 2020, the broad group Enterobacteriaceae was split into seven separate families belonging to the order Enterobacterales that is equivalent to the old Enterobacteriaceae sensu lato (Adeolu et al., 2020). Ready-to-use petrifilms selective for Enterobacteriaceae (now Enterobacterales) are available from 3M. To our knowledge, these petrifilms have not previously been used in combination with antibiotics, but the somewhat similar 3M coliform petrifilms have been used to screen and discriminate E. coli resistant for ampicillin, cephalothin, streptomycin, chloramphenicol, cefotaxime and gentamicin. The minimum inhibitory concentrations (MICs) were at the same levels as for conventional Mueller-Hinton II agar (Wu et al., 2008). The E. coli petrifilm method required higher oxytetracycline break-point concentrations than typically used in Mueller-Hinton media due to higher calcium and magnesium concentrations in the petrifilms. The E. coli petrifilm metod was not suitable for sulphamethoxazole (Wu et al., 2008). We used the results from this study to extend the petrifilm method to the order Enterobacterales (Enterobacteriaceae sensu lato) instead of only the species E. coli. The European Committee on Antimicrobial Susceptibility Testing (EUCAST, 2024) gives minimum inhibitory concentrations (MICs) for antibiotics that are effective against Enterobacterales. Within each class of these antibiotics, we aimed at compounds sold in large quantities in the Danish primary sector to test antibiotics with high probability of producing resistant bacteria that may end up in the urban environment after sewer overflow 24 and WWTP bypass. We therefore started the method development with a survey of antibiotics used in Denmark to choose compounds relevant for counting resistant Enterobacterales in the stormwater samples. In Annex B, we have listed sales statistics for antibiotics used in Denmark in the primary, medical sector for systemic use in 2021. This means antibiotics used in private homes which is the most likely source of antibiotics and antibiotic-resistant bacteria in local stormwater and local nature-based solutions for handling the stormwater such as rain beds, infiltration ditches and retention ponds. Sales of main groups of antibiotics in the primary sector in 2021 were identified in medstat.dk. Active compounds in different groups were identified at promedicin.dk. Penicillins (beta-lactams) were some of the most sold antibiotics in Denmark. Of the penicillins effective against Enterobacterales amoxicillin was chosen because it was sold in the largest quantities (Annex B). For amoxicillin, we used 4 x MIC R as selective concentration in petrifilms and Mueller-Hinton agar plates (Table 3). Of the fluoroquinolones effective against Enterobacterales, ciprofloxacin was chosen because it was the most sold in Denmark (Annex B). Ciprofloxacin is a second-generation fluoroquinolone (beta-lactam) and was previously the standard treatment for Salmonella infections. For ciprofloxacin, we used a high concentration compared to the MIC R breakpoint (Table 3) to avoid background growth of non-resistant bacteria. The aminopyrimidine antibiotic trimethoprim is used to treat Enterobacterales urinary tract infections (EUCAST, 2024). We therefore included trimethoprim in the stormwater screening. Trimethoprim was applied in concentrations four times the EUCAST Enterobacterales MIC R breakpoint (Table 3). The common tetracyclines doxycycline and tetracycline are not recommended by EUCAST against Enterobaceterales. However, we still chose tetracycline as screening compound because tetracycline resistance genes were included in the screening of stormwater resistance genes. Tetracycline (oxytetracycline) has furthermore been used in E. coli-selective petrifilms, which meant that we could draw on this method (Wu et al., 2008). The selective concentration in E. coli-petrifilm is high due to divalent Mg and Ca ions, which lower the effect of tetracyclines (Wu et al., 2008). In the Enterobacterales petrifilm screening of stormwater, we used the same tetracycline concentration as recommended for oxytetracycline in the E. coli petrifilm (Wu et al., 2008), but half the concentration in Mueller-Hinton agar due to low Mg and Ca content. Sulfamethoxazole is the only sulfonamide recommended by EUCAST for Enterobacterales and applied together with trimethoprim for urinary tract infections (EUCAST, 2024). Sulfonamides were not selected as coliform petrifilm cannot be used with sulfamethoxazole (Wu et al., 2008) which likely also applies to Enterobacterales petrifilm and probably also other sulfonamides. Carbapenems were not applied as they are “last resort antibiotics” with very limited use in Denmark and therefore with limited selection pressure in the sources of urban stormwater. Carbapenems are furthermore unstable in aqueous solution (Fawaz et al., 2018.). Table 3. Antibiotics concentrations used in the petrifilms and agar plates. Stof EUCAST Enterobacterales MIC (breakpoint R), mg/L Concentration in Enterobacteriaceae petrifilm, mg/L Concentration in Mueller-Hinton agar mg/L Amoxicillin 8 32 32 Trimethoprim 4 16 16 Tetracycline - 64 32 Ciprofloxacin 0.5 4 4 25 The antibiotics were stored at minus 80 °C. 100-fold concentrated stock solutions were prepared in autoclaved water (amoxicillin 3.2 mg/mL and ciprofloxacin 0.4 mg/mL) or methanol (trimethoprim 1.6 mg/mL and tetracycline 6.4 mg/mL), distributed in eppendorf tubes and stored at minus 80 °C until use. The antibiotics were thawed right before use and any remaining, thawed antibiotic was discarded after use. 1.5-ml subsamples of dilution series from the E. coli counts, containing natamycin to limit growth of yeasts and fungi, were added 15 µl of antibiotic stock solution, mixed, and 1-ml aliquots were added to Enterobacteriaceae petrifilm. The Petrifilms were incubated in closed plastic bags for 22-24 hours at 36°C. (Figure 16). According to the manufacturer’s instructions “Enterobacteriaceae are red colonies with yellow zones and/or red colonies with gas bubbles with or without yellow zones “, but the formation of yellow zones was difficult to clearly identify (Figure 16). Enterobacterales CFU was therefore counted only as colonies with gas production, which means that the counts are minimum estimates. Figure 16. Inoculation of petrifilm with stormwater (left) and petrifilm with ciprofloxacinresistant Enterobacterales bacteria (the gas producers) from Po01 stormwater containing combined sewer overflow at (right). The resistant CFU varied between the antibiotics from detectable amoxicillin-resistant Enterobacterales in stormwater from most of the stations to tetracycline-resistant Enterobacterales mostly in the few stations impacted by domestic sewage (Figure 17). The variation between stations was up to four orders of magnitude for amoxicillin-resistant CFU. Petrifilm Enterobacterales colonies from Copenhagen, Odense and Santander stations were tested for growth on conventional agar plates to confirm that the counted colonies were indeed resistant. The picked colonies represented different types of stations at the three sites as well as all four antibiotics. Mueller-Hinton agar was autoclaved and cooled to <45 °C before addition of antibiotics and immediately poured into petri-dishes on the days of counting petrifilms. 140 colonies were picked from the petrifilms, suspended in 1 ml fosfate buffer (10 mM, pH=7,0) and streaked on the agar followed by incubation for 22-24 hours at 36°C (Figure 18). Colonies from the agar plates were picked and suspended in glycerol (25% v/v) and stored frozen at minus 80 °C. 32 and paper. HMMM is furthermore used as a crosslinking agent in the production of coatings and rubber items for instance in car tires. Figure 22. Occurrence of myristamine oxide in stormwater samples; peak intensity was normalized to the internal standard atrazine-desisopropyl-D5. Figure 23. Algicide for sale at a Danish supermarket. The active substance is the quaternary ammonium compound didecyldimethylammoniumchloride (0,5% w/w). The product is intended for removing algae from: “hard surfaces such as cement, fiber-cement, concrete, terracotta, wood, glass, metal, plastic, solar panels, brick, roofs, facades, wooden terraces, garden furniture, fences and so on. For annual maintenance”. 5.3.4 Accumulation of organic micropollutants during dry periods. In section 5.1.3, we showed that DOC concentration was correlated with the length of dry period but not correlated to the amount of precipitation. To test whether accumulation could also account for the variation in organic micropollutants, we investigated the correlation between concentration of targets or signal intensity of suspects and dry period in street runoff samples (Figure 24), which is the predominant station type. Several pollutants typical of wastewater showed accumulation, including caffeine (R2 = 0.73) and the nicotine metabolite cotinine (R2 = 0.91). For most other compounds groups, there were no clear accumulation 0 50 100 150 200 250 300 350 Co01 Co02 Co03 Co04 Co05 Co06 Co07 Co08 Co09 Co10 Co11 Co12 Lj01 Lj02 Lj03 Lj04 Lj05 Od01 Od02 Od03 Od04 Od05 Od06 Od07 Od08 Po01 Po02 Po03 Po04 Po05 Ri01 Ri02 Ri03 Sa01 Sa02 Sa03 Sa04 Sa05 Normalized intensity N,N-Dimethylalkylamine oxide C14 (myristamine oxide) 33 trends. Dibenzylamine, a vulcanization agent that has previously been shown to indicate vehicle-related pollution (Kang et al, 2024; Müller et al., 2022), did accumulate between rain events (R2 = 0.70) but surprisingly, accumulation was not observed for other typical rubber compounds such as 1,3-diphenylguanidine (R2 = 0.45) and 6PPD-quinone (R2 = -0.03). . Figure 24. Concentration of selected micropollutants versus the number of dry days before sampling. Only stations with street runoff. 34 6 Overall discussion The overall aim was to answer the questions: 1. Which pollutants are present in European stormwater and at which concentration levels, and 2. Are there major differences between mixed stormwater and local stormwater sources. The last question is especially important as most previous stormwater studies have analyzed mixed urban stormwater collected from large areas, but the stormwater to be handled in nature-based solutions (NBS) is often of very local origin such as in street rain beds and infiltration ponds in residential areas. Composition and concentrations may vary over time for each station depending on season and the local sources; the aim of our sampling campaign was not to capture this variation as most stations were sampled only once. By sampling more stations than in previous reports, we instead aimed at describing the variation withinand between different types of source stormwater rather than repeated sampling of few single stations. We found that the load of antibiotic resistance is high in some types of urban stormwater. The highest levels were in combined sewer overflow and wastewater treatment plant bypass. This is not surprising as both stormwater types are rainwater mixed with domestic sewage. When people are treated with antibiotics, resistant bacteria are enriched in the gut and bladder from where they end up in the wastewater. We detected resistance to sulfonamides and to lesser extend tetracyclines in almost all sample though the concentrations varied with more than five orders of magnitude with highest concentrations in combined sewer overflow and lowest concentrations in roof runoff. Sul and tet genes have previously been associated with urban runoff in an urban stream (Garner et al., 2017) and water from three storm drains in Nanjing (Zou et al., 2022), this seems to be a general picture. BlaCTX and BlaNDM genes are extended spectrum betalactamase genes where the host bacterium can be resistant to a range of antibiotics, sometimes including last resort antibiotics. These genes are known from domestic sewage, but previously have not been detected in urban runoff. Trace elements are still of concern in urban stormwater despite many years’ attention. Trace elements were generally associated with combined sewer overflow and street runoff, though sometimes found in high concentration at other station types. Concentrations of trace elements were generally high in samples with much suspended material and high turbidity. This is fully in line with previous results from streams in pristine areas, where we have shown that a considerable fraction of acid-extractable trace elements was associated with suspended silt and clay particles (Moedt et al., 2025). Lead (Pb) was above the environmental threshold of 7.2 μg/L in 13 out of 38 analyzed stations and was thus the trace element with most exceedances. Lead has many sources in the city environment, the most well-known is the former use of leaded gasoline that has caused a general, diffuse contamination of surface soil in city environments. Lead also originates from roofing, thermos windows (1950’ties and 1960’ties), sewer fittings, cable coatings, ceramic glaze, outdoor paint, and as a stabilizer in PVC plastics (Annex A and Renover-sikkert, 2024). The highest lead-concentration was found in roof runoff from houses with roof tiles with ceramic glaze (Co10; 51 μg/L) that are a well-known source of lead (Hjelmer et al., 2018). High concentrations of other trace metal often also had probable sources at the stations. Zinc (Zn), for instance, showed highest concentration (2600 μg/L) at station Lj05 which is drainage from an artificial football field. The football field had a toplayer of granulated black rubber, that probably contained 1-2% zinc oxide (DEPA, 1997), which would explain the high 35 Zinc concentration. Zinc was previously recognized as an important pollutant in leacheate from recycled car tire crumb rubber (Halsband et al., 2020). Organic micropollutants in urban stormwater are anthropogenic, organic compounds found in low concentration, typically in µg/L or ng/L. They comprise many classes of organic compounds such as pesticides/biocides, industrial compounds, pharmaceuticals, etc. The target analyses with full quantification showed the presence of pollutants that indicate specific pollution sources such as domestic sewage, and rubber and traffic. Suspect screening furthermore indicated the occurrence of various quaternary ammonium compounds and a wide range of additional suspect compounds. We found that rubber compounds from the wear of car tires are a major contaminant class in street runoff and consequently also in combined sewer overflow. Many of the rubber compounds in our samples were previously reported to leach from car tire rubber (Halsband et al., 2020; Johannessen et al., 2022; Foscari et al., 2024), and some have been found in urban runoff (Challis et al., 2021). Pharmaceutical compounds were typically found in combined sewer overflow. Some pharmaceuticals were also found in low concentration in street runoff and runoff from residential areas, where the sources are less obvious. Possible sources are unintended mixing with sewage in residential areas and possibly people urinating in the streets. Quaternary ammonium compounds are a group of biocidal surfactants used for indoor disinfection and in cleaning products for outdoor surfaces (Arnold et al., 2023). A major application in the urban environment is removal of algae from facades and terraces which explains high concentrations in some samples of street runoff and from residential areas, and the general occurrence in combined sewer overflow that collects water from larger areas. There is very little information on the occurrence of quaternary ammonium compounds in stormwater in the scientific literature, but a recent study confirmed that they are common in urban stormwater runoff in high concentration (Li et al., 2025). Implications: First, it is important to avoid surface-pollution with sewage in the urban environment. Keeping sewage separate from surface runoff will reduce the exposure to pharmaceuticals, antibiotic-resistant bacteria and other sewage-related contaminants. Second, it is important to remember that nature-based solutions for handling stormwater in the cities should not only be about water volumes; water quality may be just as important. 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Potential stormwater pollutants identified in reports from the Danish Environmental Protection Agency CAS RN Building materials (Bester et al., 2022) Crushed concrete, brick and roof tile (Hjelmer et al., 2018) Surface-treated roof tile, concrete, fiber-cement (Hjelmar et al., 2020) Biocides used in Denmark (Lassen et al., 2001) Outdoor cleaning agents (Pedersen 2023) Particle-bound biocides (Vianello 2021) 1,2-Benzisothiazolin-3-one 2634-33-5 x x x 1,2-Propylene glycol 57-55-6 x 1,3,5-Triazine-2,4,6-(1H,3H,5H)-trione, 1,3-dichloro-, 2893-78-9 1,3-Bis(hydroxymethyl)-5,5dimethylimidazolidine-2,4-dione 6440-58-0 x 1-H-benzotriazole 95-14-7 x 2-(Dimethylamino)-2-methylpropan-1-ol 7005-47-2 x 2,2′,2′′-(Hexahydro-1,3,5-triazine-1,3,5triyl)triethanol 4719-04-4 x x 2,2′-Dithiobis[N-methylbenzamide] 2527-58-4 x 2,2-Dibromo-2-cyanoacetamide 10222-01-2 x 2,2'-Dithiobis[N-methylbenzamide] 2527-58-4 x 2-(2-butoxyethoxy)/2-(2-butoxyethoxy) ethanol 112-34-5 x 2,6-Di-tert-butyl-p-cresol 128-37-0 x 2-Bromo-2- (bromomethyl)pentanedinitrile 35691-65-7 x 2-Bromo-2-nitro-1,3-propanediol 52-51-7 x 2-Butylbenzo[d]isothiazol-3-one x 2-Chloroacetamide 79-07-2 x 2-Chloro-N-(hydroxymethyl)acetamide 2832-19-1 x 2-Ethylhexanol polyglycol ether phosphoric acid ester, 111798-26-6 x 2-Methyl-1,2-benzothiazol-3(2H)-one 2527-66-4 x 2-Methyl-4-isothiazolin-3-one 2682-20-4 x x 2-Methylphenol 95-48-7 x (2-Methoxymethylethoxy)propanol 34590-94-8 x 2-Phenoxyethanol 9004-78-8 x x x x (2-(tert-Butylamino)-4- (cyclopropylamino)-6-(methylthio)- 1,3,5-triazine) x 41 3,5,7-Triaza-1-azoniatricyclo[3.3.1.13,7 ]decane, 1-(3-chloro-2-propenyl)-, chloride 4080-31-3 x 4,4-Dimethyloxazolidine 51200-87-4 x 4-Chloro-3,5-dimethylphenol 88-04-0 x 4-Chloro-3-methylphenol 59-50-7 x 4-Methylphenol 106-44-5 x Al x Alcohols C12-14, ethoxylated 68439-46-3 x Alcohols,_C9-11_ethoxylated 68424-85-1 x Alkyldimethylbenzylammoniumchlorid 85409-22-9 x Alkylimidazoliniumcarboxylat 68604-71-7 x Alkylpolyglykosid C10-16 110615-47-9 x Ametryne 834-12-8 x Anthraquinone 84-65-1 x As x x x Azoxystrobin 131860-33-8 x B x Ba x x Benzalkoniumchloride 63449-41-2 x benzenesulfonamide, N-chloro-4methyl-, sodium 127-65-1 x Benzenesulfonic,acid,1-methylethyl 28348-53-0 x Benzoic acid, 2-hydroxy-, methyl ester 119-36-8 x Benzoic acid, 4-hydroxy-, methyl ester 99-76-3 x Benzoic acid, 4-hydroxy-, propyl ester 94-13-3 x (Benzyloxy)methanol 14548-60-8 x Benzothiazol-2-ylthio)methyl thiocyanate 21564-17-0 x Benzylalkohol 100-51-6 x Benzyl isothiazolinone 2634-33-5 x x Benzyl salicylate 118-58-1 x Biphenyl-2-ol 90-43-7 x x Bronopol 52-51-7 Carbamic acid, butyl-, 3-iodo-2propynyl ester 55406-53-6 x Carbendazim 10605-21-7 x x x Cd x Ce x Co x Cocoamidopropylbetaine 61789-40-0 x Cr x x x Cu x x x Cybutryne 28159-98-0 x Denatonium benzoate 3734-33-6 x Dichloro-N-[(dimethylamino)sulphonyl] fluoro-N-(ptolyl)methanesulphenamide 731-27-1 x x Dichlorooctylisothiazolinone 64359-81-5 x x x Didecyldimethylammoniumchlorid 7173-51-5 x Dimethyldithiocarbamate 128-04-1 x Diuron x x DNOC 534-52-1 x Dodecyldimethylaminoxid 1643-20-5 x EDTA 64-02-8 x Fenuron 101-42-8 x Stations in Greater Copenhagen (Denmark) Zoom Map no. Station ID Station name Station type 1 Co01 Nybrogade Street 2 Co02 Rigensgade Street 3 Co03 Fields Roof 4 Co04 Rolighedsvej Street 5 Co05 Metro Roof 6 Co06 Værløse Street 7 Co07 Drabæk Huse Street 8 Co08 Fælledparken Football 9 Co09 Brønshøj Football 10 Co10 Østervoldgade. Roof 11 Co11 Pile Alle Street 12 Co12 Damhus CSO Co01 - Nybrogade Date of sampling: 26/06/2023 Name of the person who carried out the sampling and institution: Thomas Karlsson, UCPH Short description of site and mode of sampling: Nybrogade. Manual sampling with subsurface sampler from manhole receiving combined roof and street runoff from stormwater drains. Older inner city area (predominantly 19th century buildings) with light traffic, urban squares, pedestrian shopping streets. Total catchment area: 1,05 Ha. More information: Tidsbegrænset Udledningstilladelse til UØ60, Pilotprojekt om "Low flow diversion" som renseløsning ved udledning af almindeligt belastet regnvand til Københavns Havn 2/19 Country: Denmark City/town: Copenhagen Position: 55.6758856019551, 12.575312432869598 Estimated time since previous rain event (>1 mm per day) if known: 10 days, otherwise estimate 7-14 days 15-21 days 21-28 days >28 days Sources, drained area Single houses/terraced residential area, estimate decade(s) for dominant buildings: X Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: 18 th -19 th century Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type: X Traffic/street Parking lots Mixed stormwater X Risk of mixing with municipal sewage X Other (describe) Urban squares & pedestrian shopping streets Pavement, drained area (if relevant for drained area, major components only) X Concrete/concrete slabs/cement slabs X Asphalt/bitumen Gravel X Cobble stones Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) X “Raw” bricks X Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) X Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit X Metal roofing/metal shingles/painted metal Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles X Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): Not available 0 min: 15 min: 30 min: 45 min: 60 min: 75 min: 90 min: 120 min: ARJ: According to DMI’s weather archive: 6,9 mm Manhole used for sampling, in the background discharge point into Slotsholmskanalen. View of catchment area from sampling point. Catchment area description. Co02 - Rigensgade Date of sampling: 26/6-2023 Name of the person who carried out the sampling and institution: Anders Johnsen, GEUS Short description of site and mode of sampling: Rigensgade, Street runoff from city street, sampled where water enters a storm drain. Storm drain, central Copenhagen (behind GEUS). Older multi-storey buildings, downpipes from roofs lead directly onto the street, rolled asphalt roofs, plastered facades, cobblestone road, concrete slabs pavement, parking spaces. Manual sampling Country: Denmark City/town: Copenhagen Position: GPS coordinates from Google Maps on a mobile phone: 55.6883901 12.5835269 Estimated time since previous rain event if known: 34 days, Determined from DMI's weather archive where it rained a lot on 23 May (5mm), smaller rainfall events according to DMI on 16 and 17 June (3 and 1 mm) are not registered by the rain collector on GEUS' roof. otherwise estimate 7-14 days 15-21 days 21-28 days >28 days Sources, drained area Single houses/terraced residential area, estimate decade(s) for dominant buildings: x Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: 1853 https://www.hovedstadshistorie.dk/ny-koebenhavn/rigensgade/ Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type: x Traffic/street x Parking lots Mixed stormwater Risk of mixing with municipal sewage Other (describe) Pavement, drained area (if relevant for drained area, major components only) x Concrete/concrete slabs/cement slabs Asphalt/bitumen Gravel x Cobble stones Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) “Raw” bricks x Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit Metal roofing/metal shingles/painted metal x Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): Sampling startet 15:29 (start of rain event, t0), samples taken every 15 min. No rain gauge. A short intense event (10 min) followed by light precipitation until 17:05. A total of 5 mm (measured by sampler on GEUS roof). 7 samples (0-90 min, no t120 sample). Estimated 70% of the water came from the roofs, the rest from the street (cobble stones, no asphalt) and the pedestrian pavement (concrete slabs). Drained area and sampling point: x View from storm drain, SSW (main drained area) View from storm drain, NNE Water from roof at storm drain. Samples Manhole where samples were collected. Picture taken towards the end of the rain event. Co04 - Rolighedsvej Date of sampling: 31/08/2023 Name of the person who carried out the sampling and institution: Daniele Martuscelli, UCPH/ITS Short description of site and mode of sampling: Residential area. Manual sampling of stormwater entering the drain at the side of the road. Because of the topography of the road, runoff mainly drains from one side of the road (see picture). Buildings from around 1930’s, parked cars and medium trafficked roads. Local shops include a dry-cleaner, bike repair shop, and restaurants. Country: Denmark City/town: Copenhagen Position: 55.68488499192096, 12.540308007021087 Estimated time since previous rain event (>1 mm per day) if known: 5 days, otherwise estimate Determined from DMI weather archive for Copenhagen 7-14 days 15-21 days 21-28 days >28 days Sources, drained area Single houses/terraced residential area, estimate decade(s) for dominant buildings: X Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: 1930’s Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type: X Traffic/street X Parking lots Mixed stormwater Risk of mixing with municipal sewage X Other (describe) Shops, including dry-cleaner and bicycle repair shop Pavement, drained area (if relevant for drained area, major components only) X Concrete/concrete slabs/cement slabs X Asphalt/bitumen Gravel Cobble stones Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) X “Raw” bricks Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) X Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit Metal roofing/metal shingles/painted metal Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles X Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): Not available 0 min: 0 15 min: 2,5 30 min: 4,5 45 min: 5,7 60 min: 6,2 75 min: Rain stopped. 90 min: 120 min: Map of catchment area. View of sampling station. Catchment area and sampling point marked. Because of the topography of the road, runoff flow predominantly from one side of the road and uphill from the sampling point. Sampling point during sampling. Co05 – Metro Date of sampling: 31/08/2023 Name of the person who carried out the sampling and institution: Flavia Gravina UCPH Short description of site and mode of sampling: Roof runoff from newly constructed residential buildings. Runoff from the roofs is led in separate sewage network and released in the nearby canal (Hovedkanal City). Sampling: Manual sampling with sub-surface grab sampler from separate sewage line (roof runoff only). Country: Denmark City/town: Copenhagen Position: 55.63398317287694, 12.581168231816752 Estimated time since previous rain event (>1 mm per day) if known: 5 days, otherwise estimate Determined from DMI weather archive for Copenhagen 7-14 days 15-21 days 21-28 days >28 days Sources, drained area: X Single houses/terraced residential area, estimate decade(s) for dominant buildings: 2005-2010 Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type: Traffic/street Parking lots Mixed stormwater X Risk of mixing with municipal sewage Not suspected, but potentially there could be mis-connection in sewage network. Other (describe) Pavement, drained area (if relevant for drained area, major components only) Concrete/concrete slabs/cement slabs Asphalt/bitumen Gravel Cobble stones Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) “Raw” bricks Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit Metal roofing/metal shingles/painted metal X Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles Roofing felt (tagpap) based on satellite photos from Google Maps Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): 0 min: 0,5 15 min: 3,0 30 min: 3,7 45 min: 4,2 60 min: Rain stopped – only very light rain afte this point with no visible runoff flow 75 min: 90 min: 120 min: Map of sampling station, catchment area and discharge into nearby canal. Manhole where samples were collected with catchment area behind. View of discharge point into canal. Co06 - Vaerlose Date of sampling: 31/8-2023 Name of the person who carried out the sampling and institution: Anders Johnsen, GEUS Short description of site and mode of sampling: Suburban residential area. Inlet to street rain bed receiving water from driveways, pavement and street, sampled from inlet to rainbed. Manual sampling Country: Denmark City/town: Værløse Position: GPS coordinates from Google Maps on a mobile phone: 55.7809192 12.3558112 Estimated time since previous rain event if known: 4 days, Determined from DMI's weather archive (Furesø Municipality) otherwise estimate 7-14 days 15-21 days 21-28 days >28 days Sources, drained area x Single houses/terraced residential area, estimate decade(s) for dominant buildings: 1970’ties Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type: x Traffic/street x Parking lots Mixed stormwater Risk of mixing with municipal sewage Other (describe) Pavement, drained area (if relevant for drained area, major components only) x Concrete/concrete slabs/cement slabs x Asphalt/bitumen x Gravel Cobble stones Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) “Raw” bricks Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Other (describe) Roofing (if relevant for drained area, major components only) Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit Metal roofing/metal shingles/painted metal x Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles Shale slate shingles (natural) x Plastic/PVC Precipitation readings (accumulated): Sampling started 9:03. Sample 1 0 min: 0 mm Sample 2 15 min: 1 mm Sample 3 30 min: 1 mm Sample 4 45 min:1,5mm Sample 5 60 min: 2,0mm Sample 6 75 min: 2,2 mm Sample 7 90 min: 2,7 mm Sample 8 120 min: 3,7 mm Total during sampling: 3,7 mm Further characterization of station: Terraced houses with many infiltration ponds and infiltration ditches. The drained area had street, driveways, terraces, and parking lots that drain to a ditch at a single point. When full, the ditch has overrun to a small stream (South). Dotted lines: water from roofs is first lead to cobble beds halfway to the street. The water runs to the street and further to the NBS only during heavy rain (not during the sampled rain event). The trench receives overrun from upstream ponds and ditches downstream the sampling point. Catchment area View from sampling point towards South. Sampling point Infiltration trench with overrun pipe from upstream ponds and trenches Facade Samples Co08 – Fælledparken Date of sampling: 23/11-2023 Name of the person who carried out the sampling and institution: Thomas Karlsson (UCPH) Short description of site and mode of sampling: Drain from football field with rubber granulate infill, constructed in 2012. Sampling from bottom of manhole using sub-surface grab sampler. NB: Heavy shower (approximately 2-3 mm) during the morning before sampling. Light rain during sampling with continuous flow into manhole. Country: Denmark. City/town: Copenhagen. Position: 55.706363623451736, 12.570442380423584 Estimated time since previous rain event (>1 mm per day) if known: 0 days, otherwise estimate Rain during the morning before sampling. 7-14 days 15-21 days 21-28 days >28 days Sources, drained area Single houses/terraced residential area, estimate decade(s) for dominant buildings: 2017 Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type: Traffic/street Parking lots Mixed stormwater Risk of mixing with municipal sewage x Other (describe) Artificial football field with rubber granulate infill. Pavement, drained area (if relevant for drained area, major components only) Concrete/concrete slabs/cement slabs Asphalt/bitumen Gravel Cobble stones Lawn (cut grass) x Other (describe) Artificial football field with rubber granulate infill. Building facades, drained area (if relevant for drained area, major components only) “Raw” bricks Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit Metal roofing/metal shingles/painted metal Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): NB: Not measured on-site – data from DMI for Copenhagen area. High uncertainty because of highly local precipitation patterns. From DMI: Total during sampling: 1,9 mm (seems approximately correct from estimation on-site). Sampling started: 10.25. Drainage area. Sampling point Sampling area with sampling point Samples Co09 – Brønshøj Date of sampling: 23/11-2023 Name of the person who carried out the sampling and institution: Flavia Gravina (UCPH) Short description of site and mode of sampling: Drain from football field with kork infill, constructed in 2020. Samples from continuous flow into manhole (i.e. not from the bottom) using sub-surface grab sampler. NB: Heavy shower (approximately 2-3 mm) during the morning before sampling. Varying precipitation with occasional heavy showers during sampling with continuous flow into manhole for the whole duration. Country: Denmark City/town: Brønshøj. Position: GPS coordinates from Google Maps on a mobile phone: 55.71935114083969, 12.495103198985248 Estimated time since previous rain event (>1 mm per day) if known: 0 days, otherwise estimate Rain during the morning before sampling. 7-14 days 15-21 days 21-28 days >28 days Sources, drained area Single houses/terraced residential area, estimate decade(s) for dominant buildings: 2017 Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type: Traffic/street Parking lots Mixed stormwater Risk of mixing with municipal sewage x Other (describe) Artificial football field with kork infill. Pavement, drained area (if relevant for drained area, major components only) Concrete/concrete slabs/cement slabs Asphalt/bitumen Gravel Cobble stones Lawn (cut grass) x Other (describe) Artificial football field with kork infill. Building facades, drained area (if relevant for drained area, major components only) “Raw” bricks Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit Metal roofing/metal shingles/painted metal Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): NB: Not measured on-site – data from DMI for Copenhagen area. High uncertainty because of highly local precipitation patterns. From DMI: Total during sampling: 1,9 mm (estimated to be a lot more). Sampling started: 10.15 Drainage area. Samples Co11 – Pile Alle Date of sampling: 5/4/2024 Name of the person who carried out the sampling and institution: Paula Toma (UCPH) Short description of site and mode of sampling: Road runoff from a large hill (Valby Bakke) with a lot of traffic. Sampling from side of the road with bicycles and car/bus traffic. Country: Denmark City/town: Copenhagen Position: 55.670806527385665, 12.530530640007786 Estimated time since previous rain event if known: 1 days, otherwise estimate 7-14 days 15-21 days 21-28 days >28 days Sources, drained area Single houses/terraced residential area, estimate decade(s) for dominant buildings: Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type: x Traffic/street Parking lots Mixed stormwater Risk of mixing with municipal sewage Other (describe) Pavement, drained area (if relevant for drained area, major components only) Concrete/concrete slabs/cement slabs x Asphalt/bitumen Gravel Cobble stones Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) “Raw” bricks Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit Metal roofing/metal shingles/painted metal Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): 0 min: 1.0  Light rain before runoff started 15 min: 1.5 30 min: 2.5 45 min: 3.5 60 min: 4.5 75 min: 6.5 - Rain stopped 90 min: Not collected 120 min: Not collected Further characterization of station: Road with lots of traffic from cars and buses. Sampled from side of the road where water flow primarily downhill from Valby Bakke. Beside the road is a park on one side and the zoo on the other. Samples Sampling spot (NB: view is downhill, not the direction of the primary runoff flow) Catchment area Co12 - Damhus Date of sampling: 5/4/2024 Name of the person who carried out the sampling and institution: Thomas Karlsson (UCPH) Short description of site and mode of sampling: Combined sewer overflow from Damhusåen Renseanlæg, Copenhagen. Sampled from inlet to biological treatment basin (bypass where overflow most commonly happens at this WWTP). Country: Denmark City/town: Copenhagen Position: Large-scale site (see map of catchment area below). Sampling was done at: 55.63824464346471, 12.506972585125107 Estimated time since previous rain event if known: 1 days, otherwise estimate 7-14 days 15-21 days 21-28 days >28 days Sources, drained area Single houses/terraced residential area, estimate decade(s) for dominant buildings: Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type: Traffic/street Parking lots x Mixed stormwater Risk of mixing with municipal sewage Other (describe) Pavement, drained area (if relevant for drained area, major components only) Concrete/concrete slabs/cement slabs Asphalt/bitumen Gravel Cobble stones Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) “Raw” bricks Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit Metal roofing/metal shingles/painted metal Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): 17:45 18:00 18:15 18:30 18:45 19:00 0 min: 1.0 mm 15 min: 2.0 30 min: 2.5 45 min: 3.5 60 min: 4.7 75 min: 6.0 -Rain stopped 90 min: Not collected 120 min: Not collected Further characterization of station: Combined sewage from Western part of the larger Copenhagen area including Valby, Hvidovre, Rødovre, Brønshøj, and Vanløse. Sampling from bypass at inlet to biological treatment basin, which is where wastewater overflow is most often discharged from during heavy rain events at this WWTP. Manual sampling by collecting from sink with a continuous flow of wastewater. Samples WWTP catchment area Sampling done by collecting from this sink which has a continuous flow of wastewater from the inlet to biological treatment basin. Stations in Ljubljana (Slovenia) Zoom Map no. Station ID Station name Station type 1 Lj01 Grosuplje Roof 2 Lj02 Bizovik Street 3 Lj03 Logatec Sewage 4 Lj04 Brinje stormwater pipe Residential 5 Lj05 Brinje football field Football Lj01 - Grosuplje Date of sampling: 11/02/2024 Name of the person who carried out the sampling and institution: Tina Kosjek, Jožef Stefan Institute Short description of site and mode of sampling: Roof runoff. Manual sampling of a runoff from a ≈50 yrs old roof on a sawmill building in a suburban area, nearby highway. Vicinity of individual fireplaces, hence deposited particles, combustion products are expected in the samples. Country: Slovenia City/town: Grosuplje, approximately 17 km from Ljubljana city center Position: 45.969323, 14.698148 Estimated time since previous rain event (>1 mm per day) if known: < 1 day (with no clear start of the rain event), otherwise estimate 7-14 days 15-21 days 21-28 days >28 days Sources, drained area Single houses/terraced residential area, estimate decade(s) for dominant buildings: Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: X Small industry, if possible, specify type: Traffic/street Parking lots Mixed stormwater Risk of mixing with municipal sewage Other (describe) Pavement, drained area (if relevant for drained area, major components only) Concrete/concrete slabs/cement slabs Asphalt/bitumen Gravel Cobble stones Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) “Raw” bricks Mortar plaster/painted mortar plaster/painted bricks X Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) Larger catchment area, Ljubljana Bizovik, 11.2.2024, Foto: Dušan Žigon Lj03, Logatec - municipal WWTP bypass Date of sampling: 10/03/2024 Name of the person who carried out the sampling and institution: Tina Kosjek, JSI Short description of site and mode of sampling: WWTP Logatec, outlet. This is a municipal WWTP with a capacity of 14900 PE, which receives domestic wastewaters and wastewaters from paper printing industry. The WWTP uses a mixed stormwater bypass during heavy rains. It is thus expected to load enteric indicators, anthropogenic biomarkers, dyes and possibly antibiotic resistance. Country: Slovenia City/town: Logatec Position: 45.91472275101508, 14.231678215774858 Estimated time since previous rain event (>1 mm per day) if known: < 1 day (with no clear start of the rain event), otherwise estimate 7-14 days 15-21 days 21-28 days >28 days Sources, drained area Single houses/terraced residential area, estimate decade(s) for dominant buildings: Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: X Small industry, if possible, specify type: paper printing industry Traffic/street Parking lots X Mixed stormwater X Risk of mixing with municipal sewage Other (describe) Pavement, drained area (if relevant for drained area, major components only) Concrete/concrete slabs/cement slabs Asphalt/bitumen Gravel Cobble stones Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) “Raw” bricks Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit Metal roofing/metal shingles/painted metal Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): 0 min: 0.0 mm ZERO 30 min: 0.2 mm SINCE START 60 min: 0.7 mm SINCE START 105 min: 1.7 mm SINCE START T = 7 °C Samples collected / time of sampling WWO-1 / 12:31 WWO-2 / 12.47 WWO-3 / 12:59 WWO-4 / 13:13 WWO-5 / 13:29 WWO-6 / 13:44 WWO-7 / 13:59 WWO-8 / 14:12 WWTP outlet. Logatec, 10.3.2024, Photo: Tina Kosjek Larger area: WWTP outlet. Logatec, 10.3.2024, Photo: Tina Kosjek Lj04Brinje stormwater pipe surface water, residential area Date of sampling: 10/03/2024 Name of the person who carried out the sampling and institution: Tina Kosjek, JSI Short description of site and mode of sampling: Collected at recipient canal from outlet pipe that drains surface water from a residential area in Grosuplje – Brinje. There is a primary school with a parking lot in front and an athletic stadium and a playground. Next to it there is a residential area with new houses (from after 2010) and back a bit up the hill a bit older single houses (from 1980’s) . After the rain stopped, the water from the black pipe that leads into the Grosupeljščica stream ceased very quickly so the collection of the very last sample was not possible anymore. Country: Slovenia City/town: Grosuplje Position: 45.96245450459853, 14.658800499670006 Estimated time since previous rain event (>1 mm per day) if known: < 1 day (with no clear start of the rain event), otherwise estimate 7-14 days 15-21 days 21-28 days >28 days Sources, drained area X Single houses/terraced residential area, estimate decade(s) for dominant buildings: 1980-2015 Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type X Traffic/street X Parking lots X Mixed stormwater Risk of mixing with municipal sewage Other (describe) Pavement, drained area (if relevant for drained area, major components only) Concrete/concrete slabs/cement slabs X Asphalt/bitumen X Gravel Cobble stones X Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) “Raw” bricks X Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit X Metal roofing/metal shingles/painted metal Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): 19:50 START: 0.0 mm ZERO 20:10 min: 4.2 mm SINCE START 20:24 min: 5.7 mm SINCE START 20:39 min: 7.0 mm SINCE START 20:48 min: 7.7 mm SINCE START 21:09 min: 9.0 mm SINCE START 21:16 min: 9.2 mm SINCE START – RAIN STOPPED T = 5 °C Samples collected / time of sampling ST-1 / 19:52 ST -2 / 20:06 ST -3 / 20:20 ST -4 / 20:36 ST -5 / 20:51 ST -6 / 21:06 ST -7 / 21:21 At the time of sampling it was already dark, so I couldn’t take a photo, but here is one from earlier. Grosuplje-Brinje, 11.2.2024, Photo: Tina Kosjek Lj05 – Brinje football field Date of sampling: 10/03/2024 Name of the person who carried out the sampling and institution: Tina Kosjek, JSI Short description of site and mode of sampling: Grosuplje – Brinje: drainage from artificial football field plus one with a natural grass next to it. Right next to the field two pipes open alternately every few minutes (on a heavy rain occasion) and water is discharged down the drain into the stream (Grosupeljščica). Country: Slovenia City/town: Grosuplje Position: 45.961860663631015, 14.658894376981424 Estimated time since previous rain event (>1 mm per day) if known: < 1 day (with no clear start of the rain event), otherwise estimate 7-14 days 15-21 days 21-28 days >28 days Sources, drained area Single houses/terraced residential area, estimate decade(s) for dominant buildings: Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type Traffic/street Parking lots Mixed stormwater Risk of mixing with municipal sewage X Other (describe): artificial football field plus one with a natural grass next to it Pavement, drained area (if relevant for drained area, major components only) Concrete/concrete slabs/cement slabs Asphalt/bitumen Gravel Cobble stones X Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) “Raw” bricks Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit Od02, Hørdumsgade Date of sampling: 29/10/2023 Name of the person who carried out the sampling and institution: Rikke Hansen VCS Short description of site and mode of sampling: For instance: Rain bed in residential area, sampled from inlet Manual sampling X Country: Denmark City/town: Odense Position: GPS coordinates from Google Maps on a mobile phone: 55.409271, 10.393100 Estimated time since previous rain event (>1 mm per day) if known: 1 days, otherwise estimate 7-14 days 15-21 days 21-28 days >28 days Sources, drained area x Single houses/terraced residential area, estimate decade(s) for dominant buildings: 1930 Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type: Traffic/street Parking lots Mixed stormwater Risk of mixing with municipal sewage Other (describe) Pavement, drained area (if relevant for drained area, major components only) X Concrete/concrete slabs/cement slabs X Asphalt/bitumen Gravel Cobble stones Lawn (cut grass) Other (describe) Pavement tiles Building facades, drained area (if relevant for drained area, major components only) x “Raw” bricks Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete x Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit Metal roofing/metal shingles/painted metal Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): Sample 1 0 min: Sample 2 15 min: Sample 3 30 min: Sample 4 45 min: Sample 5 60 min: Sample 6 75 min: Sample 7 90 min: Sample 8 120 min: Rain gauge forgotten, Odense precipitation from DMI weather archive: 4,4 mm in 2 hours. Further characterization of station: Receives water from street, pavement, and parking lots. * * Od03 - Kallerupvej Date of sampling: 29/10/2023 Name of the person who carried out the sampling and institution: Nana Benthien, VCS Short description of site and mode of sampling: For instance: Rain bed in residential area, sampled from inlet. Receives water only from street and parking lots. Manual sampling X Country: Denmark City/town: Odense Position: GPS coordinates from Google Maps on a mobile phone: 55.377217, 10.403978 Estimated time since previous rain event (>1 mm per day) if known: 1 days, otherwise estimate 7-14 days 15-21 days 21-28 days >28 days Sources, drained area x Single houses/terraced residential area, estimate decade(s) for dominant buildings: 1970 Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type: Traffic/street Parking lots Mixed stormwater Risk of mixing with municipal sewage Other (describe) Pavement, drained area (if relevant for drained area, major components only) X Concrete/concrete slabs/cement slabs X Asphalt/bitumen Gravel Cobble stones Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) “Raw” bricks Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit Metal roofing/metal shingles/painted metal Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): Sample 1 0 min: 7:20 Sample 2 15 min: 7:35 Sample 3 30 min: 7:50 Sample 4 45 min: 8:05 Sample 5 60 min: 8:20 Sample 6 75 min: 8:35 Sample 7 90 min: 8:50 Sample 8 105 min: 9:05 Rain gauge forgotten, Odense precipitation from DMI weather archive: 4,4 mm in 2 hours. . Od04 Søparken North (TN); Od05 Søparken South (TS) Date of sampling: 29/10/2023 Name of the person who carried out the sampling and institution: Thor Hougaard, VCS Short description of site and mode of sampling: Inlet to retention pond at a residential area, sampled from inlet pipes, two pipes – North and South. Most water is evaporated or infiltrated from the pond, runoff from pond only in extreme rain events. Manual sampling X Country: Denmark City/town: Odense Position: GPS coordinates from Google Maps on a mobile phone: TN: 55.352902, 10.366980 Brønd G30R591 TS: 55.352590, 10.366814 Brønd G30R581 Estimated time since previous rain event (>1 mm per day) if known: 1 days, otherwise estimate 7-14 days 15-21 days 21-28 days >28 days Sources, drained area x Single houses/terraced residential area, estimate decade(s) for dominant buildings: 1970 Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type: Traffic/street Parking lots Mixed stormwater Risk of mixing with municipal sewage Other (describe) Pavement, drained area (if relevant for drained area, major components only) X Concrete/concrete slabs/cement slabs X Asphalt/bitumen Gravel Cobble stones X Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) X “Raw” bricks X Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) X Roof tiles (terracotta-, clayor cement/concrete tiles) X Fiber cement plates/eternit X Metal roofing/metal shingles/painted metal Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): Sample 1 0 min: Sample 2 15 min: Sample 3 30 min: Sample 4 45 min: Sample 5 60 min: Sample 6 75 min: Sample 7 90 min: Sample 8 120 min: Rain gauge forgotten, Odense precipitation from DMI weather archive: 4,4 mm in 2 hours. Further characterization of station: * North inlet Od07 - Thulevej Date of sampling: 15/11/2023 Name of the person who carried out the sampling and institution: Per Rasmussen VCS Short description of site and mode of sampling: Overflow/bypass from municipal WWTP, sampled from bypass pipe X Autosampler X Country: Denmark City/town: Odense Position: GPS coordinates from Google Maps on a mobile phone: 55.415476, 10.348006 Estimated time since previous rain event (>1 mm per day) if known: 1 days, otherwise estimate 7-14 days 15-21 days 21-28 days >28 days Sources, drained area X Single houses/terraced residential area, estimate decade(s) for dominant buildings: Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: X Small industry, if possible, specify type: X Traffic/street X Parking lots X Mixed stormwater X Risk of mixing with municipal sewage Other (describe) Pavement, drained area (if relevant for drained area, major components only) X Concrete/concrete slabs/cement slabs X Asphalt/bitumen Gravel Cobble stones X Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) “Raw” bricks Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Large catchment area, properly all of the above Roofing (if relevant for drained area, major components only) Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit Metal roofing/metal shingles/painted metal Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): Sample 1 0 min: Sample 2 15 min: Sample 3 30 min: Sample 4 45 min: Sample 5 60 min: Sample 6 75 min: Sample 7 90 min: Sample 8 120 min: No data from this station. Sampling time: 20:35-22:35 Precipitation in this time interval according to Danish Meteorological Institute : 6,0 mm Od08 Gartnerbyen Date of sampling: 23.05.2024 Name of the person who carried out the sampling and institution: Nina Almind Jørgensen, VCS Thor Hougaard, Anura Short description of site and mode of sampling: Inlet to long narrow retention pond at a newly constructed residential area, sampled from pond water at inlet pipe Manual sampling Country: DK City/town: ODENSE Position: GPS coordinates from Google Maps on a mobile phone: 55.397692, 10.360869 Estimated time since previous rain event (>1 mm per day) if known: 17 days 7-14 days X 15-21 days 21-28 days >28 days Sources, drained area X Single houses/terraced residential area, estimate decade(s) for dominant buildings: new (2 years) Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: Small industry, if possible, specify type: Traffic/street X Parking lots Mixed stormwater Risk of mixing with municipal sewage Other (describe) Pavement, drained area (if relevant for drained area, major components only) X Concrete/concrete slabs/cement slabs X Asphalt/bitumen Gravel Cobble stones X Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) X “Raw” bricks Mortar plaster/painted mortar plaster/painted bricks X Wood/painted wood/impregnated wood X Concrete Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit Metal roofing/metal shingles/painted metal X Rolled asphalt roofing/bitumen roofing felt/asphalt composite shingles Shale slate shingles (natural) Plastic/PVC Precipitation readings (accumulated): 09:55 10:10 10:25 10:40 10:55 11:10 11:25 11:40 Sample 1 0 min: Sample 2 15 min: Sample 3 30 min: Sample 4 45 min: Sample 5 60 min: Sample 6 75 min: Sample 7 90 min: Sample 8 120 min: Read from the Danish national weather archive (dmi.dk, Årslev ) 9:40 (start of rain) to 11:40: 13,1 mm Further characterization of station: Before industrial area, now new residential area. Catchment area also includes an office building with parking slots to the northeast (TV2). * Stations in Pontedera (Italy) Map no. Station ID Station name Station type 1 Po01 Via Hangar CSO 2 Po02 Via Agnoletti CSO 3 Po03 Via Roma Street 4 Po04 Piazza Cavour Street 5 Po05 Shopping mall Street Po01 - Via Hangar Date of sampling: 09/02/2024 Name of the person who carried out the sampling and institution: Francesca Marvulli, Acque SpA – Tutela della Risorsa Idrica, Via A. Bellatalla ,1 - 56121 Ospedaletto (PI) Short description of site and mode of sampling: Overflow/bypass from municipal WWTP, sampled from bypass pipe Manual sampling YES Country: Italy City/town: Pontedera Position: GPS coordinates from Google Maps on a mobile phone: 43.663722, 10.615019 Estimated time since previous rain event (>1 mm per day) if known: 22/01/2024 - 17 days 7-14 days X 15-21 days 21-28 days >28 days Sources, drained area X Single houses/terraced residential area, estimate decade(s) for dominant buildings: X Inner city, old buildings (typically <1930) estimate decade(s) for dominant buildings: X Inner city, new buildings (typically >1950) estimate decade(s) for dominant buildings: X Small industry, if possible, specify type: automotive/motorcycle (Piaggio &C.) X Traffic/street X Parking lots X Mixed stormwater X Risk of mixing with municipal sewage Other (describe) Pavement, drained area (if relevant for drained area, major components only) X Concrete/concrete slabs/cement slabs X Asphalt/bitumen Gravel Cobble stones X Lawn (cut grass) Other (describe) Building facades, drained area (if relevant for drained area, major components only) “Raw” bricks X Mortar plaster/painted mortar plaster/painted bricks Wood/painted wood/impregnated wood X Concrete X Metal/painted metal Fiber cement plates/painted fiber cement/ceramic tiles Other (describe) Roofing (if relevant for drained area, major components only) X Roof tiles (terracotta-, clayor cement/concrete tiles) Fiber cement plates/eternit X Metal roofing/metal shingles/painted metal