Prevalence of human pathogens and indicators in stormwater runoff in Brisbane, Australia J.P.S. Sidhu a,b, *, L. Hodgers a , W. Ahmed a,b , M.N. Chong a , S. Toze a,c a CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, Brisbane 4102, Australia b Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore, DC, QLD 4558, Australia c School of Population Health, University of Queensland, Herston Road, Herston, Brisbane, QLD 4006, Australia article info Article history: Received 4 August 2011 Received in revised form 1 March 2012 Accepted 5 March 2012 Available online 16 March 2012 Keywords: Stormwater Fecal indicator bacteria Adenovirus Polyomavirus Campylobacter spp. Salmonella enterica abstract Elevated numbers of enteric pathogens in the receiving waters following a storm event can be a serious public health concern. The purpose of this study was to conduct a preliminary investigation into the presence of human pathogens of concern in urban stormwater runoff. The involvement of a human sewage as a potential source of contamination was also investigated by using microbial source tracking methods. Water samples (20 L) were collected after storm events and during the dry weather from six sites in Brisbane, Australia. Collected samples were analyzed for fecal indicator bacteria (FIB), and then concentrated using hollow fiber ultrafiltration followed by molecular detection of selected enteric pathogens. The levels of FIB were found to frequently exceed the upper limit of Australian guidelines for managing risks in recreational water, during the dry periods and by further several orders of magnitude in the stormwater runoff. Enterococcus spp. numbers as high as 3  10 4 100 mL 1 were detected in the stormwater runoff at the Fitzgibbon site. Human adenovirus and polyomavirus were frequently detected from all six sampling sites during wet and dry weather conditions suggesting their wide spread presence in the urban aquatic environments. Campylobacter jejuni, Campylobacter coli and Salmonella enterica were also detected during both dry and wet weather conditions. Presence of human-specific HF183 Bacteroides marker in most of the samples tested suggests ubiquitous sewage contamination in the urban environment. Since stormwater runoff routinely contains high numbers of FIB and other enteric pathogens, some degree of treatment of captured stormwater would be required if it were to be used for non-potable purposes. Crown Copyright ª 2012 Published by Elsevier Ltd. All rights reserved. 1. Introduction Urban stormwater is a relatively untapped alternate water source in Australia (Hatt et al., 2006), which can be used to augment non-potable and potable water supplies within cities and other urban areas. Potential presence of fecal contami- nation in stormwater runoff (Parker et al., 2010; Sauer et al., 2011) however, can negatively impact public health if polluted surface water bodies are used for recreational purposes or captured stormwater is used for non-potable purposes such as gardening and landscape irrigation. Concerns over this issue are heightened by the reported links between the occurrence of storm events, microbial inputs from non-point sources and increase in the incidence of waterborne diseases (Curriero et al., 2001; Gaffield et al., 2003). Thus, it is important to understand the presence and * Corresponding author. CSIRO Land and Water, Ecosciences Precinct, 41 Boggo Road, Brisbane 4102, Australia. Tel.: þ61 7 3833 5576; fax: þ61 7 3833 5503. E-mail address: Jatinder.Sidhu@csiro.au (J.P.S. Sidhu). Available online at www.sciencedirect.com journal homepage: www.elsevier.com/locate/watres water research 46 (2012) 6652 e6660 0043-1354/$ e see front matter Crown Copyright ª 2012 Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.watres.2012.03.012