Abstract
This paper reports on the results of a study aimed at identifying the presence or absence of humansourced faecal material in stormflows from three urbanised non-sewered catchments in South-East Queensland. To date, only a limited number of studies have been undertaken in Australia aimed at unambiguously detecting pollutant exports from failing septic trenches using a wide range of techniques. Six different pollutant source tracking techniques were used to identify human faecal contamination from up to six storm events in each of three non-sewered catchments. These techniques included Biochemical fingerprinting of E.coli and enterococci, faecal sterol analysis and the human specific genetic biomarkers Bacteroides HF183, Bacteroides HF134 and enterococci surface protein gene (esp). The study found that there was indeed a consistent presence of human-sourced faecal indicators in all three study catchments. However, compared to other potential catchment faecal sources (such as birds, dogs and native animals) the human-sourced proportion of faecal load may be relatively low. This study also found that the results obtained from faecal source tracking methods used in isolation may give ambiguous results, leading to the recommendation that a range of techniques be used for future investigations to provide confidence in results.