title: Influence of pollutant build-up on variability in wash-off from urban road surfaces.
abstract: Variability in the pollutant wash-off process is a concept which needs to be understood in-depth in order to better assess the outcomes of stormwater quality models, and thereby strengthen stormwater pollution mitigation strategies. Current knowledge about the wash-off process does not extend to a clear understanding of the influence of the initially available pollutant build-up on the variability of the pollutant wash-off load and composition. Consequently, pollutant wash-off process variability is poorly characterised in stormwater quality models, which can result in inaccurate stormwater quality predictions. Mathematical simulation of particulate wash-off from three urban road surfaces confirmed that the wash-off load of particle size fractions < 150 μm and > 150 μm after a storm event vary with the build-up of the respective particle size fractions available at the beginning of the storm event. Furthermore, pollutant load and composition associated with the initially available build-up of < 150 μm particles predominantly influence the variability in washed-off pollutant load and composition. The influence of the build-up of pollutants associated with > 150 μm particles on wash-off process variability is significant only for relatively shorter duration storm events.
authors.affiliation: Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, 4001, Queensland, Australia. Electronic address: b.mahappukankanamalage@qut.edu.au.
authors.forename: Buddhi
authors.initials: B
authors.lastname: Wijesiri
authors.affiliation: Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, 4001, Queensland, Australia. Electronic address: p.egodawatta@qut.edu.au.
authors.forename: Prasanna
authors.initials: P
authors.lastname: Egodawatta
authors.affiliation: Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, 4001, Queensland, Australia. Electronic address: james.mcgree@qut.edu.au.
authors.forename: James
authors.initials: J
authors.lastname: McGree
authors.affiliation: Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, 4001, Queensland, Australia. Electronic address: a.goonetilleke@qut.edu.au.
authors.forename: Ashantha
authors.initials: A
authors.lastname: Goonetilleke
mesh_terms: D004784:Environmental Monitoring; D015386:Hazardous Substances / Q000032:analysis*; D008956:Models, Chemical; D011891:Rain; D014186:Transportation; D014872:Water Movements
chemical_list: D015386:Hazardous Substances
keywords: Particle size; Pollutant build-up; Pollutant wash-off; Process variability; Stormwater pollutant processes; Stormwater quality