Urban stormwater quality monitoring: From sampling to water quality analysis

This paper presents the outcomes of urban stormwater quality monitoring and research including associated activities in South East Queensland (SEQ). The issues associated with urban stormwater quality monitoring, ranging from automated field sampling to laboratory analysis of chemical, toxicological and microbiological constituents present in stormwater are elaborated. A medium density residential stormwater supply catchment of 290 hectares in northern Brisbane is presented as a case study and discussed in detail. Preliminary results indicate that the occurrence and concentration of chemical pollutants in urban stormwater runoff and the associated baseline toxicity is relatively low. However, the microbiological quality of stormwater may not be as good as initially perceived with high numbers of faecal indicator bacteria (FIB) detected during wet weather events. In addition, the polymerase chain reaction (PCR) detection of pathogens indicated the presence of human sewage contamination during wet weather events which might be due to potential sewer overflow events. Further monitoring will be conducted to further assess the stormwater quality before undertaking a comprehensive environmental and public health risk assessment.