Understanding the impact of the primary defecation events (biological contamination) on drinking water catchments

In Australia, waterborne communicable diseases (CD) is a recognised health concern for individuals living in remote and indigenous communities, where monitoring has shown that, in some jurisdictions, only 70% of water supplies consistently meet national health targets. Further, rising natural disasters (floods/cyclones) have also resulted in increases in associated infectious diseases. However, the health and economic burdens associated with waterborne disease in Australia remain unknown with no national system of surveillance and reporting. The One Water Group is a multidisciplinary, multi-partner research team focused on understanding waterborne CD in Australia. In particular, the group has a specific focus on health-related urban water microbiology with projects in 1) Understanding the pathways to disease, 2) Development of mobile and passive sampling methods for use in water-based epidemiology and risk assessment, and 3) Understanding microbial community dynamics in complex environments through molecular and genomic technologies. PROJECT Waterborne communicable diseases are considered a major public health issue resulting in significant morbidity and substantial economic losses worldwide. Faeces contributed by human and domestic/ wild animal populations represent significant biological contamination and the introduction of pathogenic microorganisms into the water sources, either through direct defecation of overland flow. This program will focus on understanding faecal loads in the riparian zones of the water bodies, as well as insight into the movement, transport, and survival of faecal-derived microorganisms within closed catchments. To achieve this, we will use geospatial tools to map the location of animal scat around the reservoirs and combine it with animal survey data, collected by Melbourne Water to the development of a spatiotemporal scat map in the riverbank of the catchments. Concurrently, sewage samples from local wastewater treatment plants will be collected and undergo equivalent analysis to determine pathogen loads within local human populations. Students will gain the ability to utilize molecular and culture-based techniques to understand the sources and survival of microbial pathogens such as Escherichia coli, Enterococci, Campylobacter spp., Salmonella spp., and Cryptosporidium spp. Where identified there will be an opportunity to gain further skills in whole genome sequencing using Oxford Nanopore Technology and associated bioinformatics to determine the species and subspecies risk profiles of identified pathogens. Information that will be directly provided to governing bodies to inform local risk assessment and mitigation activities.