A fecal analysis survey was undertaken to quantify animal inputs of pathogenic and indicator microorganisms in the temperate watersheds of Sydney, Australia. The feces from a range of domestic animals and wildlife were analyzed for the indicator bacteria fecal coliforms and Clostridium perfringens spores, the pathogenic protozoa Cryptosporidium and Giardia, and the enteric viruses adenovirus, enterovirus, and reovirus. Pathogen and fecal indicator concentrations were generally higher in domestic animal feces than in wildlife feces. Future studies to quantify potential pathogen risks in drinking-water watersheds should thus focus on quantifying pathogen loads from domestic animals and livestock rather than wildlife.The current trend in minimizing pathogen health risks to water supplies is to use a risk management-based approach to ensure delivery of high-quality water. This approach utilizes multiple barriers within the water system, including effective control of contaminant inputs through watershed management. One potential source of these pathogens in drinkingwater watersheds is the feces of domestic and wildlife animal populations. Pathogens from animal feces may enter waterways by direct deposition or as a result of overland runoff containing fecal material deposited in the watershed. To construct a source material budget of pathogen inputs, it is necessary to estimate the potential impact of animal populations on surface water quality (15). Subsequent analysis can then be performed to estimate the proportion of the source material that will be inactivated through natural decay and environmental stressors, how much may be transported to the stream network, and the proportion that represents a risk of human infection.The initial requirement for the development of a source material budget is to estimate the concentration of potential pathogens in animal feces (shedding intensity). There is limited published information on the concentration and input load of potential waterborne pathogens and fecal indicator bacteria in wildlife (native and feral animal) populations (2,3,8,19). Yet it is these animals that often have the greatest access to the riparian zones and reservoir surrounds in watersheds, since, by definition, their movements are largely uncontrolled, making surface water protection difficult. By comparison, data for potential pathogen concentrations in the feces of domestic animals are more abundant, particularly for the enumeration and prevalence of the protozoan parasites Cryptosporidium and Giardia spp. (4-7, 18, 24, 25).This study was undertaken to provide a cross-sectional estimate of the intensity of shedding of pathogenic and indicator microorganisms in animal feces present in a large, semiprotected drinking-water watershed. The study quantified potentially pathogenic protozoa (Cryptosporidium and Giardia), enteric viruses (adenovirus, enterovirus, and reovirus), and indicator organisms (fecal coliforms and Clostridium perfringens spores) in fecal samples from watershed animals. The latter are t...

Aims: Currently cryptosporidiosis represents the major public health concern of water utilities in developed nations and increasingly, new species and genotypes of Cryptosporidium are being identified in which the infectivity for humans is not clear. The complicated epidemiology of Cryptosporidium and the fact that the majority of species and genotypes of Cryptosporidium cannot be distinguished morphologically makes the assessment of public health risk difficult if oocysts are detected in the raw water supplies. The aim of this study was to use molecular tools to identify sources of Cryptosporidium from the Warragamba catchment area of Sydney, Australia. Methods and Results: Both faecal and water samples from the catchment area were collected and screened using immunomagnetic separation (IMS) and immunofluorescence microscopy. Samples that contained Cryptosporidium oocysts were genotyped using sequence and phylogenetic analysis of the 18S rDNA, and the heatshock (HSP-70) gene. Analysis identified five Cryptosporidium species/genotypes including C. parvum (cattle genotype), C. suis, pig genotype II, the cervid genotype and a novel goat genotype. Conclusions: Monitoring and characterization of the sources of oocyst contamination in watersheds will aid in the development and implementation of the most appropriate watershed management policies to protect the public from the risks of waterborne Cryptosporidium. Significance and Impact of the Study: This study has shown that quantification by IMS analysis can be combined with the specificity of genotyping to provide an extremely valuable tool for assessing the human health risks from land use activities in drinking water catchments.

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The Sydney Harbour waterway modelling suite examines the changes in water quality in the harbour estuary and its tributaries associated with stormwater runoff and wet weather sewage overflows from the upstream catchments, in Sydney Australia. This paper discusses the development and performance of the numerical models. The models have been used to investigate the spatial variability of catchment pollutant loads and the impacts of sewer overflows on the water quality in the Sydney Harbour estuary. The scenario modelling results demonstrate that sewer overflows have a minimal impact on the Sydney Harbour estuary water quality, with stormwater dominating most changes in water quality.

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