FORM TITLE - Request for Project Funding Environmental E. coli

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1 Working title: Management of Environmental E. coli Problem statement: The presence of Environmental E. coli challenges the assumption that E. coli are always an indicator of recent faecal contamination of water. In particular, the ability of some types of Environmental E. coli to grow to high densities in engineered raw water storages in the absence of recent faecal contamination, combined with the unusual characteristics of these naturally-occurring blooming E. coli, means that water utilities require further knowledge of the efficacy of treatment barriers to remove or inactivate these microorganisms, supported by the development of a management framework for this microorganism, which could be incorporated into the Australian Drinking Water Guidelines (ADWG). Background/ Description: The presence of Environmental E. coli blooms was first noted in Australian lakes in the 1970s, primarily along the east coast of Australia. It is characterised by rapid bloom growth, with cell counts reaching >10,000cfu/100mL, followed by a rapid collapse that might occur days to weeks later. Investigation of affected water bodies during these events was not been able to identify a credible faecal source to explain the high cell numbers. Over the last thirty years many studies have challenged the universal validity of E. coli as a faecal indicator organism by demonstrating the ability of E. coli to survive for extended periods of time, and even grow to high densities, in various secondary habitats, including soils, sediments, beach sands and aquatic vegetation. Experts reflecting on the ability of E. coli to survive in various environments have suggested that it may be attributable to E. coli s vast genetic diversity, as high genetic diversity generally improves a species' adaptability and resistance to environmental changes. In Australia, there has been no attempt to systematically assess the distribution or nature of Environmental E. coli, particularly the subset of blooming E. coli, until recently. Knowledge of the existence of Environmental/blooming E. coli was restricted to a small number of utilities and regulators who had experience in dealing with them over many years. As more geographic sites had E. coli bloom detections, water utilities and regulators that were guided by the ADWG were forced to assume that the elevated E. coli counts were indicative of massive recent faecal pollution of unknown source, despite no other water quality parameter supporting this conclusion. Moreover, E. coli counts in catchments are a key determinant of catchment risk classification in the coming inclusion of microbial Health Based Targets in the ADWG, which is based upon the validity of the assumption that E. coli s presence in the natural environment is the result of recent faecal contamination. Following more widespread informal reporting of E. coli blooms around Australia, funding was obtained for an ARC Linkage project (2012), led by ANU (David Gordon), with 11 partners from around Australia, which further investigated a large number of Environmental E. coli isolates and found that the subset of bloomforming isolates from South East Qld, NSW and the ACT were often the same 3 to 4 strains. They all have a distinctive Klebsiella-like capsule, which gives a characteristic mucoid colony type on agar plates and is hypothesised to aid in their long-term environmental persistence. These strains were usually detectable in water bodies, such as lakes or reservoirs, where they exist at low levels outside of bloom periods. The eastern bloom isolates (ACT, Sydney, Hunter, and Gold Coast) have never been isolated from a vertebrate host, nor do they carry antibiotic resistance genes or the genes required to colonise a host and cause disease. Considering this information, these bloom-forming organisms are unlikely to represent a public health risk. 1 Page

2 The project team demonstrated that, beyond the blooming E. coli strains, there were a diverse range of Environmental E. coli that can survive for extended periods in engineered water bodies. These isolates, while they may have originally had a faecal origin in the distant past, have been selected over extended periods of time for survival as free-living bacteria and certainly do not represent recent faecal contamination. The recent investigation into Western Australia s first recorded E. coli bloom provided further complexity. While the two strains of blooming E. coli that were isolated had the typical mucoid capsule, they also had a small number of virulence-associated genes and some antibiotic resistance genes on a plasmid. This does not necessarily mean that the isolates have been recently selected by antibiotic pressure, as the plasmid may contain other genes that confer a selective advantage for environmental survival, or it may indicate that this particular plasmid cannot be ejected without killing the cell. However, it does indicate that more has to be learnt about strain variation across Australia and care should be taken when applying knowledge from well-studied sites to new bloom sites. Australian water utilities have varying experience, expertise and decision frameworks for managing these bloom events and rely on case-by-case communication with their health regulators to manage each bloom event, due to the lack of guidance on this subject in the ADWG. Part of the management approach utilises current techniques to distinguish blooming E. coli from other strains, based on the distinctive capsule, as well as the history of previous blooms on the water body under similar conditions and no evidence of a proportionate faecal source. Because blooming E. coli strains could suggest massive water contamination, they may trigger major water quality incidents with expensive consequences if authorities cannot quickly demonstrate that they are not of faecal origin. Regulators and utilities could more rapidly and reliably downgrade their responses and adjust their risk assessments if there was a rapid, accurate test to identify blooming strains of E. coli. This would include having clear justification for removing bloom counts from drinking water catchment risk rankings. While regulators and utilities could better assess the true likelihood of an E. coli count representing recent faecal contamination of water through the development of rapid and accurate methods to differentiate the broad group of Environmental E. coli, from E. coli that are highly likely to have recently come from faeces (faecal E. coli, or FEC), the possibility of such a test will not be known until work underway at the Institute Pasteur in Paris is completed and is beyond the scope of the currently planned research outlined here. There is also limited knowledge of the treatment susceptibilities of Environmental E. coli. For example, the thick mucoid capsule of blooming strains may confer increased disinfectant resistance. The water industry, regulators and the community would benefit from understanding how current treatment processes remove, inactivate or reduce environmental E. coli, particularly blooming strains, so that the likelihood of breakthrough into treated drinking water can be rapidly assessed. Objectives: The objectives of this project are to: Raise awareness of the issue of Environmental E. coli within Australian water sources Development of a rapid identification method for the individual identification of the five currently characterised bloom strains of E. coli Develop decision making rules that inform a risk-based response to Environmental E. coli Investigate the efficacy of current treatment processes to remove, inactivate or reduce Environmental E. coli Develop communication messages to provide public reassurance on this topic Alignment with strategy: 2 Page

3 ADWG requires inclusion of a Factsheet within the ADWG Microorganisms Microbial indicators section WaterRA contained within the Managing Contamination in Water focus area HBT requires consideration of advice provided within the HBT Manual to differentiate between faecallyderived E. coli and Environmental E. coli, especially in relation to blooms. Primary deliverable: Decision making framework for water utilities to assist with the management of Environmental E. coli, with improved identification techniques, guidance on treatment processes for Environmental E. coli, assessment of what conditions may trigger a bloom and the development of communication messages to provide public reassurance on this topic. Title Description Research is further required to: Why Improve the identification techniques for blooming E. coli Need to know if an E. coli result is or is not due to one of the known blooming strains. To achieve this we need a reliable (quick) test to differentiate blooming E. coli from other E. coli. 1. Understand if there are genes or gene variants that are consistent within blooming E. coli which can be utilised to identify blooming E. coli. Initial funding for this is $30k 2. If gene/gene variant is identified then rapid techniques will be developed that utilise this. Funding for this is $50k and dependent on 1. being successful 3. If gene/gene variant not identified is there an alternative method? Funding to be determined A rapid, accurate test to differentiate blooming E. coli from other E. coli will ensure that utilities and health regulators can quickly eliminate the bloom counts as a reflection of faecal contamination. This includes the accurate estimation of drinking water catchment risks where E. coli is used as the risk indicator by excluding bloom counts from risk assessments. Efficacy of current treatment processes Currently little data on how effective current treatment processes are to deal with Environmental E. coli, particularly under bloom conditions Provide evidence to regulators on effectiveness of standard treatment (Coag/Floc/Disinfect (Cl)) processes to treat Environmental E. coli. Funding required is $100k Assurance that treatment is an effective barrier Bloom predictability Understand if there are Analyse the existing data available from water storages that have experienced E. coli blooms to If bloom events can be predicted for a 3 Page

4 environmental conditions that predispose to or influence bloom formation determine what factors or conditions are similar to those associated with past bloom events. The analysis needs to consider the regional, site specific nature of the data. Identify potential trigger conditions for a bloom. Funding required is $50k with industry in-kind support for data required. given water source it will assist with management response and provide further evidence that the E. coli at these times is not faecally derived These techniques and knowledge will be combined to support the development of a decision support tool and guidance document to assist water utilities and regulators manage Environmental E. coli bloom events. Other deliverables: WaterRA will work with the project team to raise awareness of this issue, which includes the development of a Factsheet to be disseminated by WaterRA. Further liaison will be conducted with the NHMRC/WQAC on the incorporation of a Factsheet on this issue into the ADWG. Communication plan: Utilities the project will significantly benefit from engaging with utilities that have experienced blooms previously and have an established management response. However, as the evidence from WA suggests, a bloom may occur for no apparent reason, and it would be beneficial for utilities to know that there are management approaches for dealing with a bloom should it occur. Regulators Regulators, particularly those in states that experience Environmental E. coli blooms, will require engagement on the development of the decision support framework that adequately manages any identified risk to human health and which can be consistently applied throughout Australia. Further engagement with NHMRC/WQAC is required for incorporation of a new Factsheet on Environmental E. coli into the ADWG. Customers as E. coli is currently assumed to be derived from only faecal matter there will need to be messaging developed that informs the community that this is not always the case, and what the significance of these blooms are to public health WSAA - as the custodian of the HBT Manual, WSAA will need to be informed of the management approach for Environmental E. coli and how this should be incorporated in establishing catchment classifications under a HBT-based framework Knowledge Transfer plan: Project Initiation stakeholder input is required for refinement of research aims; initial engagement with regulators about the need for the project Project execution - engagement with identified stakeholders, review of project progress, development of KT deliverables, assurance that the framework will meet national requirements. WaterRA will release a Factsheet on the topic, with input from the project team. Project deliverables decision support framework document to be released via WaterRA; research publications, as identified by researchers; WaterRA/researcher/project team to run workshop at OzWater 4 Page

5 2017 on Environmental E. coli topic Post-Project WaterRA, with support of researchers, to advocate to NHMRC for inclusion of an Environmental E. coli Factsheet in ADWG, WaterRA to share with members, state regulators and water directorates outcomes of the project. Consider a survey months after release to determine if framework has assisted with the management of Environmental E. coli blooms. Interested Stakeholders: Regulators Utilities, reservoir / water quality managers Indicative Funding required: Funding has been broadly assigned to the categories below: Improved identification techniques $30k + $50k (Go/No go stage depending on outcome of Phase 1. metagenomics analysis) Efficacy of current treatment processes $100k Bloom Predictability - $50k + inkind Development of management framework and communication activities - $50k Duration: The project duration is expected to be 1 year Intellectual Property: There will be background IP from ANU and development of new project IP that will be WaterRA Investigative or Research approach ANU and AWQC collaboration, with metagenomics analysis to be conducted by Institute Pasteur in Paris. Risk Management certainty regarding treatment efficacy Risk Management certainty regarding the identification of the Utility Benefits species and the associated risk to public health Productivity improved management response to environmental E. Coli bloom events with decrease in cost to manage events What are the anticipated benefits? Productivity Service Delivery Risk Management Research Partner Benefits Publication outputs Capacity Building Benefits How will this result in practice change, organisational learning or improvements for society What will success look like (KPI s)? Service Delivery assurance of public health as there is a better characterisation of the risk, which could prevent a boil water notice Uptake potential collaboration with Institute Pasteur in Paris in growing area of research with molecular methods Uptake Papers in both high calibre industry oriented and scientific journals Society more definitive communication with communities regarding the public health risk Continuity of supply reduced / avoided boil water notices Time spent managing an Environmental E. coli bloom will decrease C.t values and Log Reduction Values (LRV) for common treatment processes 5 Page

6 Indicative Funding Name:... Date:. FOR CASH FUNDING AMOUNT OF $... FOR INKIND FUNDING AMOUNT OF $... FOR FINANCIAL YEAR/S 6 Page