title: Urban stormwater harvesting and reuse: a probe into the chemical, toxicology and microbiological contaminants in water quality.
abstract: Stormwater is one of the last major untapped urban water resources that can be exploited as an alternative water source in Australia. The information in the current Australian Guidelines for Water Recycling relating to stormwater harvesting and reuse only emphasises on a limited number of stormwater quality parameters. In order to supply stormwater as a source for higher value end-uses, a more comprehensive assessment on the potential public health risks has to be undertaken. Owing to the stochastic variations in rainfall, catchment hydrology and also the types of non-point pollution sources that can provide contaminants relating to different anthropogenic activities and catchment land uses, the characterisation of public health risks in stormwater is complex, tedious and not always possible through the conventional detection and analytical methods. In this study, a holistic approach was undertaken to assess the potential public health risks in urban stormwater samples from a medium-density residential catchment. A combined chemical-toxicological assessment was used to characterise the potential health risks arising from chemical contaminants, while a combination of standard culture methods and quantitative polymerase chain reaction (qPCR) methods was used for detection and quantification of faecal indicator bacteria (FIB) and pathogens in urban stormwater. Results showed that the concentration of chemical contaminants and associated toxicity were relatively low when benchmarked against other alternative water sources such as recycled wastewater. However, the concentrations of heavy metals particularly cadmium and lead have exceeded the Australian guideline values, indicating potential public health risks. Also, high numbers of FIB were detected in urban stormwater samples obtained from wet weather events. In addition, qPCR detection of human-related pathogens suggested there are frequent sewage ingressions into the urban stormwater runoff during wet weather events. Further water quality monitoring study will be conducted at different contrasting urban catchments in order to undertake a more comprehensive public health risk assessment for urban stormwater.
authors.affiliation: CSIRO Land and Water, Ecosciences Precinct, Boggo Rd, Dutton Park, Queensland, 4102, Australia. Meng.Chong@hotmail.my
authors.forename: Meng Nan
authors.initials: MN
authors.lastname: Chong
authors.forename: Jatinder
authors.initials: J
authors.lastname: Sidhu
authors.forename: Rupak
authors.initials: R
authors.lastname: Aryal
authors.forename: Janet
authors.initials: J
authors.lastname: Tang
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Gernjak
authors.forename: Beate
authors.initials: B
authors.lastname: Escher
authors.forename: Simon
authors.initials: S
authors.lastname: Toze
mesh_terms: D002947:Cities; D004784:Environmental Monitoring; D012722:Sewage / Q000382:microbiology; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry* / Q000382:microbiology / Q000633:toxicity; D014871:Water Microbiology; D014873:Water Pollutants / Q000032:analysis* / Q000737:chemistry / Q000633:toxicity; D060753:Water Quality
chemical_list: D012722:Sewage; D062065:Wastewater; D014873:Water Pollutants