The project aims to investigate the impacts of biosolids biochar immobilized bacteria on soil microbial activity and diversity during arsenic phytoremediation.

Thesis underway.

This project has four specific objectives: (1) To identify ways to prevent or reduce the incidence of foaming during anaerobic digestion of sewage sludge; (2) to identify the core microbiome associated with efficient digestor performance during stabilisation of sewage sludge; (3) to assess how changes in the reactor environment affect contaminant transformations; (4) to assess the impacts of biosolid post-treatments on the metabolic capacity of the microbial community, pathogen-survival, contaminant-transformations and ecotoxicology of final products.

PhD Thesis underway by Timothy Micallef.

Biosolids odour impacts communities and public perception of water utilities. This project will explore how microbial community mediates variability of biosolids odour and GHG emissions using new approaches. The project aims to:
1. Develop methods to characterise microbial community structure and function with metabolomics and flow cytometry.
2. Explain the role of microbial community in regulating emissions during anaerobic incubation.
3. Investigate how the microbial community mediates emissions variability under environmental gradients.

PhD Thesis underway by Andreas Pfeifle.

This study successfully developed a variety of specific qPCR assays for the characterisation of host faecal contamination.
The results supported the coupled use of mitochondrial markers with Bacteroides markers for microbial risk assessment for improved efficiency and accuracy.

Honours Thesis completed by Sarah Aucote in November 2017.

Faecal source tracking (FST) involves the identifying the contamination pathways and potential health risk of faecal contamination in source waters and is an important strategy for contaminant management within catchments. The Smart Monitoring for Microbial Risk Assessment project (WaterRA #1103) aimed to develop and validate a protocol for FST including sampling requirements, quality standards and guidelines for data interpretation, with the objective to be able to integrate newer qPCR and vertebrate diversity profiling technologies into existing monitoring programmes.  The techniques and approach for source water characterisation using the methodologies demonstrated in Project 1103 show substantial promise in being able to provide the additional risk discrimination when assessing source waters in line with Health Based Targets guidelines.

Nevertheless, the work presented in WaterRA#1103 project identified several limitations to the wholesale utilisation of some aspects of this technology which need careful consideration before its widespread adoption across all catchment types. One of the most significant factors limiting the application of the vertebrate diversity profiling component of the technology was the amount (or lack) of starting target template available before the PCR amplification steps.

The proposed research aims to explore the application of passive samplers to source waters and examine if they can increase the target template captured available for PCR amplification and subsequent vertebrate diversity profiling, in addition to targeted qPCR analysis.  Furthermore, the proposal looks to build upon the learnings from Project 1103 ​so the molecular techniques developed can be more widely adopted to catchment risk assessment within the framework of Health Based Targets approach.

Lake hydrodynamic models are used by water utilities to provide an estimation of the conditions within a water storage. Increasingly, water utilities are employing a pathogen module to simulate the advection and dispersion of pathogens in source water. Lake model outputs provide forecasted pathogen concentrations across the water column of lakes and reservoirs, including at the offtakes of water treatment plants. This pathogen information, in combination with any monitored pathogen concentrations, provides important inputs to water quality experts to conduct quantitative microbial risk assessment.

The quality and outcomes of a lake modelling process depend on several critical steps, some of which are implicitly used by modellers, but which are often not adopted routinely or communicated widely as part of a quality assurance process. There is an emerging need in the drinking water supply industry for information and guidance on the appropriate use of lake models to support QMRAs. Ideally, the information is provided through a set of best practice guidelines that demonstrate a series of quality assurance principles and actions to ensure that model development, implementation and application represent best practice and are commensurate with the intended purpose. This project will identify, review, and communicate guidance on specific modelling steps, such as project administration, conceptual modelling framework, model evaluation metrics, and uncertainty analysis practice, and prepare consultative draft of the detailed best practice guidelines.

Antimicrobial resistance (AMR) – the ability of microorganisms to resist antibiotics, antifungals, and antivirals – is one of the greatest health threats of the 21st century. It also presents a major challenge to agricultural industries, with significant impacts for biosecurity, productivity, food safety and quality, and market access. Through focused collaboration between researchers and industry, CRC SAAFE will lead the AMR response for the Australian water, waste, agribusiness, and food sectors, anticipating and addressing future challenges and capitalising on emerging opportunities.