Water Research Australia

Antimicrobial-resistant (AMR) pathogens in drinking water plumbing systems represent a significant yet underestimated public health threat. This is the first study to use qPCR and culture-based methods to investigate the prevalence of key AMR threats, meticillin resistant Staphylococcus aureus (MRSA) and carbapenem resistant Pseudomonas aeruginosa and Acinetobacter baumannii, in Australian hospital and residential drinking water and biofilm samples. Seventy-three per cent of residential water and biofilm samples were qPCR positive for at least one target pathogen compared with 38% of hospital samples, and 45% of residential plumbing fixtures harboured at least two target pathogens. Thirty-seven per cent of water and biofilm samples were qPCR positive for P.aeruginosa, 22.3% for A.baumannii and 21.7% for S.aureus. Using culture, 10% of samples were positive for P.aeruginosa, 8% for A.baumannii and 7% for S.aureus. Of these, 29% of P.aeruginosa and 28% of A.baumannii culture isolates were carbapenem resistant, and 54% of S.aureus isolates were identified as MRSA. Drain biofilms were the most common reservoir for AMR A.baumannii, S. aureus and P.aeruginosa. Carbapenem resistance genes including blaNDM-1, blaOXA-48, blaKPC-2 and blaVIM were found in biofilm samples otherwise negative for P.aeruginosa, indicating plumbing biofilms may act as eDNA reservoirs. These findings underscore the critical role of plumbing biofilms as hotspots for diverse AMR pathogens, amplifying risks for vulnerable populations, particularly in home healthcare settings. This study highlights an urgent need for enhanced surveillance and targeted interventions to mitigate AMR risks in drinking water plumbing systems.

Context Dryland rivers are unique ecosystems, where drought and flood play an important role in shaping the ecosystem. River regulation has altered the natural flow regime in many of these systems, affecting migration cues and connectivity for many species. Aims To quantify the discharge-related movements of Murray cod and golden perch within the Condamine–Balonne River subject to differing levels of river regulation. Methods We quantified flow regime variability, river regulation and fish movement to develop generalised additive mixed models to predict movement probability for Murray cod and golden perch. Results Both species showed strong positive relationships between discharge and movement. Murray cod did not show any association with river regulation; however, medium-sized individuals were significantly more likely to move than were smaller or larger fish. Golden perch movements varied among levels of regulation, were more likely to move as body weight increased and showed seasonality of movement, moving less during winter. Conclusions This study presents the largely unobserved movement behaviours of fish across a gradient of river regulation and environmental conditions in the northern Murray–Darling Basin. Implications This information is valuable for informing policy and management decisions that may affect species’ life-history requirements in analogous river systems.

The Collaborative Seismic Environment Plan (CSEP) project was formed in 2018 by NERA (National Energy Resources Australia) and an industry consortium of marine seismic acquisition operators and exploration titleholders. Using a collaborative approach, the vision of the CSEP project was to streamline seismic survey environment plan preparation, submission and assessment by the regulator (National Offshore Petroleum Environmental and Safety Authority, NOPSEMA), with an emphasis on mutually agreed protocols with commercial fishers operating within the CSEP Operational Area. Stakeholder consultation undertaken during Environmental Plan (EP) preparation was identified by the consortium as a principal cause for concern and a common reason for unsuccessful EP submissions. The CSEP project has achieved the project’s vision through: A Commercial Fishing Industry Adjustment Protocol to provide a standardised, evidence-based process to assess and provide monetary adjustment to commercial fishers for loss of catch, displacement and gear loss/damage; an Operational Protocol to provide guidance regarding improved communications with commercial fishers, including the spatial and temporal repetition and advanced notifications of seismic activities; a single overarching approvals framework for seismic activities within the CSEP Operational Area; a consistent assessment of environmental receptors, potential impacts, and management controls for seismic activities; and Improved understanding of potential cumulative impacts of seismic activities across the CSEP Operational Area. The CSEP project is an example of best practice stakeholder consultation that can be applied to offshore oil and gas and renewable energy activities.

Abstract Aim Changes to the extent and severity of wildfires driven by anthropogenic climate change are predicted to have compounding negative consequences for ecological communities. While there is evidence that severe weather events like drought impact amphibian communities, the effects of wildfire on such communities are not well understood. The impact of wildfire on amphibian communities and species is likely to vary, owing to the diversity of their life‐history traits. However, no previous research has identified commonalities among the amphibians at most risk from wildfire, limiting conservation initiatives in the aftermath of severe wildfire. We aimed to investigate the impacts of the unprecedented 2019–2020 black summer bushfires on Australian forest amphibian communities. Location Eastern coast of New South Wales, Australia. Methods We conducted visual encounter surveys and passive acoustic monitoring across 411 sites within two regions, one in northeast and one in southeast New South Wales. We used fire severity and extent mapping in two multispecies occupancy models to assess the impacts of fire on 35 forest amphibian species. Results We demonstrate a negative influence of severe fire extent on metacommunity occupancy and species richness in the south with weaker effects in the north—reflective of the less severe fires that occurred in this region. Both threatened and common species were impacted by severe wildfire extent. Occupancy of burrowing species and rain forest specialists had mostly negative relationships with severe wildfire extent, while arboreal amphibians had neutral relationships. Main Conclusion Metacommunity monitoring and adaptive conservation strategies are needed to account for common species after severe climatic events. Ecological, morphological and life‐history variation drives the susceptibility of amphibians to wildfires. We document the first evidence of climate change‐driven wildfires impacting temperate forest amphibian communities across a broad geographic area, which raises serious concern for the persistence of amphibians under an increasingly fire‐prone climate.

Waterborne diseases are a major global problem, resulting in high morbidity and mortality, and massive economic costs. The ability to rapidly and reliably detect and monitor the spread of waterborne diseases is vital for early intervention and preventing more widespread disease outbreaks. Pathogens are, however, difficult to detect in water and are not practicably detectable at acceptable concentrations that need to be achieved in treated drinking water (which are of the order one per million litre). Furthermore, current clinical-based surveillance methods have many limitations such as the invasive nature of the testing and the challenges in testing large numbers of people. Wastewater-based epidemiology (WBE), which is based on the analysis of wastewater to monitor the emergence and spread of infectious disease at a population level, has received renewed attention in light of the current coronavirus disease 2019 (COVID-19) pandemic. The present review will focus on the application of WBE for the detection and surveillance of pathogens with a focus on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the waterborne protozoan parasites Cryptosporidium and Giardia. The review highlights the benefits and challenges of WBE and the future of this tool for community-wide infectious disease surveillance.

Abstract The occurrence of toxic cyanobacteria in surface waters and their impact on drinking water treatment plants (WTPs) is a growing, global concern. The main objective of this paper was to assess the presence of cyanobacteria in surface water sources and associated cell removal efficiency in full-scale WTPs across the world. Previously unpublished data was collected from WTPs experiencing cyanobacterial blooms in either their managed surface waters or recreational waters. In total, data were collected from 31 surface water sources and 21 WTPs in North and South America, Europe, Asia, and Australia. The most commonly detected species were identified in both the surface waters, including Microcystis, Anabaena, Nostoc, Oscillatoria, and Planktolyngbya, and water treatment plant intakes, including Microcystis, Cylindrospermopsis, Anabaena, Pseudanabaena, and Aphanizomenon. In the intakes, cyanotoxins and taste and odor (T&O) compounds frequently co-occurred (80%) as did multiple cyanotoxins (39%). Conventional treatment saw a wide range of removal depending on the density of cells, species, and metabolites. Although more than 28% of sampling events displayed negligible or even negative removals of metabolites or cells due to accumulation within the clarifier, filtration, or water recycling, the presence of multiple treatment barriers, particularly advanced treatments like granular activated carbon and nanofiltration, allowed for the cells and their metabolites of concern to be removed to below guideline values. During treatment, total microcystins were often removed without releasing their intracellular fraction, whereas cylindrospermopsin, geosmin, and 2-MIB were commonly detected as entirely extracellular at the plant's intake. The maximum tolerable cell (MTC) counts for cyanotoxin- or T&O-producing cells were calculated using guideline values, average removal efficiency, and the average cell quota derived from data. The 21 WTPs in this work were found to be able to tolerate approximately 74,000 cells/mL for microcystins, 8,000 cells/mL for cylindrospermopsin, and 1,200 cells/mL for geosmin and 2-MIB before exceeding guideline values. These levels provide guidance for water treatment plant operators to assess the potential risk associated with cells capable of producing cyanotoxins or T&O compounds.