Knowledge and research gaps
The ANZ Guidelines aim to provide up-to-date and scientifically sound guidance and guideline values for key water quality related issues in Australia and New Zealand. We aim to continually improve the knowledge base available for water quality practitioners to use, to the extent that this can be resourced.
While the Guidelines are based on rigorous scientific research, in some instances there is a lack of relevant information in the Australian and New Zealand context. For example, some of the research used to derive water quality default guideline values (DGVs) is confined to northern hemisphere species with limited research on native Australian and New Zealand species.
Identified needs
An analysis of the Water Quality Guidelines Improvement Program by Greg Claydon – stage one report 2023 and stage two report 2024 – identified several needs to improve the guidelines and associated user experience. These needs cover different aspects of the program, including improved coordination and integration, new and improved implementation and technical guidance, consideration of additional (emerging) water quality issues and specific research needs for default guideline values, as detailed in the following tables.
Targeted water quality research will help address key knowledge and research gaps, with a view to establishing a multi-year research, innovation and new knowledge plan. This will be integral to achieving the objectives of the National Water Quality Management Strategy and can usefully inform universities and other research institutions about ongoing needs to be met and opportunities for partnering and co-funding.
Broad gaps that have been identified to date by the Department of Climate Change, Energy, the Environment and Water and as part of the WQGIP review include:
- A lack of Australian and New Zealand species particularly for some of the PFAS DGVs to be developed - we have a very different environment to North America and Europe where most of this work is done.
- Key research needs for updating the Australian Guidelines for Water Recycling: Managing Health and Environmental Risks (Phase 2) - Stormwater Harvesting and Reuse; and Augmentation of Drinking Water Supplies; or possibly consolidating Phases 1 and 2 and including potable reuse.
- Research for sediments, groundwater and marine and estuarine conditions - much of the focus has been on surface water and freshwater guidelines.
Significant challenges and potential future innovations and research have also been identified:
- current and future climate change and consequent implications for hydrology, land use, water quality, ecosystem and human health, and economic, social and cultural well-being
- embracing new science, methods, technologies and the digital revolution
- changing human behaviours and expectations, including expectations around Indigenous knowledge and engagement to incorporate Indigenous cultural and spiritual values in decision-making processes
- addressing the impact of stressors on parts of the aquatic environment not well represented in the current guidelines, for example microbes and stygofauna, and the impact of stressors not well represented in the current guidelines, for example pharmaceuticals, behaviour-impacting chemicals and micro/nano plastics.
Current and potential research
The following tables provide visibility of research currently underway and also what additional research is needed to continue to maintain the currency of the ANZ Guidelines. The list of research themes is not exhaustive and is set to grow as further issues and requirements come to light.
Table 1 summarises key research and knowledge needs identified in expert workshops, and Table 2 contains details of DGVs-specific knowledge gaps identified during the preparation of DGVs technical briefs since the transition to ANZG 2018 (following the baseline of ANZECC/ARMCANZ 2000). We acknowledge that derivation of new DGVs or updating DGVs from ANZECC/ARMCANZ (2000) may be of higher priority than further strengthening recently derived DGVs.
Researchers are encouraged to partake in any of the research and knowledge needs (e.g., as postgraduate student projects) if they have the resources to do so. Where any such work is proposed, researchers should liaise and, preferably, collaborate with, the Water Quality Guidelines Secretariat at waterquality@dcceew.gov.au to ensure that the project plan and outcomes meet the needs of, and have the maximum chance of being incorporated into, the ANZ Guidelines.
Table 1. Research themes and research and knowledge needs for improved water quality guidelines and guidance development
| Research theme | Reason for further research | Research/knowledge/need |
|---|---|---|
| Risk-based approaches/ prioritisation | Where the risk to water quality is greater, to what extent do you do more (investigation, management, mitigation or other) work there, what factors should you have regard to, and how do you decide all of that? This need relates to steps 7–10 of the Water Quality Management framework (WQMF), and may assist the direction and review of the Murray–Darling Basin Plan, for example. All other relevant sectors would also benefit. | More detailed national guidance on steps 7–10 of the WQMF. Could include specific case studies to serve as examples. |
| Climate change impacts | Especially on temperatures, runoff changes and marine water acidification. | Aimed at assessing if existing DGVs are still robust under changing climate and improving the derivation process. |
| Emerging contaminants impacts | Lack of general information and guidance for:
| Collation of current knowledge on the nature and potential impacts of these contaminants, and development of guidance on assessment of risk/impact. National Chemicals Working Group to develop joint or coordinated guidance on assessing risk from Emerging Contaminants. |
| Specific ecosystem types | Under-represented ecosystems, or those requiring special consideration, include (as examples):
| More relevant or updated guidance and, in some cases, new or revised guideline values. |
| Industrial activities guidance | Key industries include (as examples):
| Additional or new guidance for assessing risk/impact (including leaving offshore oil and gas infrastructure in situ at end of life as 'artificial reefs)'. |
| Coordination of research effort | More research and visibility on contaminants of existing and emerging concern – is work being well communicated and coordinated and how is it formally feeding into the Australian and New Zealand Water Quality Guidelines Improvement Program (ANZ WQGIP) and any other related processes? | Comprehensive guidelines that go beyond current considerations, e.g., groundwater quality protection guidance to include stygofauna; microbes and AMR considered in derivation of DGVs; coordination of guidance (with National Chemicals Working Group) on assessing risk from emerging contaminants. |
| Uncertainties | Additional information and guidance about handling uncertainties in the ANZG work, and how that should be communicated to decision-makers and others. | For decision-makers and others to appropriately consider uncertainties. How “adverse effects” are defined may also have implications here. |
| Research theme | Reason for further research | Research/knowledge/need |
|---|---|---|
| Genomics/omics/eDNA | Research on and application of genomics/eDNA methods is a developing area that has implications for future approaches to water quality monitoring and assessment. | Development of national guidance on the application of genomics/eDNA methods, including strengths and limitations and guidance on most appropriate applications. |
| Novel methods | Developing Novel Approaches Methods (NAMs) acceptable for use in DGV derivation - incorporating in vitro tests, high-throughput screening, and predictive modelling. | To complement existing methods for assessment and to enhance the accuracy and efficiency of DGV and Guideline development while reducing the need for extensive animal testing. |
| Multiple stressors and mixtures | More guidance on methods and knowledge for handling multiple stressors and mixtures of contaminants, including metabolites and degradation products - improved frameworks and tools (including decision support tools) need to be developed for this. | Updated guidance on the best-practice modelling and assessment methods for assessing the effects/risks of multiple stressors and mixtures. |
| Improved DGVs derivation methods and application guidance for toxicants | Further guidance and research on areas where the standard toxicant DGVs derivation methods fail and the application of the guidelines and DGVs is currently limited. | For example:
|
| Improved local GV derivation methods and application guidance for physico-chemical stressors | Further guidance and research on areas where the existing guidance on how to derive and apply local GVs for physico-chemical stressors (e.g., pH, turbidity, nutrients) is currently limited. | For example, clearer guidance on comparison of monitoring data with GVs, especially for high ecological value systems and where ‘best available’ reference sites have been used to derive the GVs. |
| Improved technologies | Guidance on the increasing use of remote sensing and other improved technologies, collection and dissemination of data and information, provision of alerts and status reports. | To assist water quality monitoring and enabling efficiencies. |
| Handling big data | Data repositories and access under findability, accessibility, interoperability, and reusability (FAIR) principles. | Consolidating data sets (e.g., aquatic biodiversity and water quality) to make them more useable. |
Table 2. DGV knowledge gaps identified during preparation of water quality DGVs technical briefs
| Toxicant | DGV reliability | Reason for requiring further data | Additional research need | Priority* |
|---|---|---|---|---|
| Chromium (III) (fresh) | Moderate | Insufficient knowledge on the effects of key toxicity modifying factors (e.g., water hardness, alkalinity, DOC) on chromium toxicity and associated guideline values. | Further studies are required to quantify the effects of key toxicity modifying factors on chromium toxicity, to potentially enable development of bioavailability-based DGVs. | Moderate |
| Cobalt (marine) 3rd party | Very high | Paucity of data on effect of DOC on cobalt toxicity to marine species. | Additional data on the effect of DOC on chronic toxicity of cobalt to marine species, to develop DOC adjustment for DGVs. | Low |
| Cobalt (fresh) 3rd party | Moderate | Paucity of data on effect of DOC on cobalt toxicity to freshwater species. | Additional data on the effect of DOC on chronic toxicity of cobalt to freshwater species, to develop DOC adjustment for DGVs. | Low |
| Gallium (marine) 3rd party | Low | Low reliability DGVs based on only 6 toxicity values. | Chronic toxicity data for at least two additional marine species would enable the derivation of moderate or, potentially, high reliability DGVs. | High |
| Iron (freshwater) | Very high | Existence of bioavailability models for iron in freshwater from overseas, but not validated for local species/conditions. | Validation of the existing bioavailability models for iron in freshwater from overseas using Aust/NZ species in Aust/NZ water chemistries would enable adoption of bioavailability-based DGVS for iron in freshwater. | Moderate |
| Iron (marine) | Moderate | Paucity of data on effect of DOC on iron toxicity to marine species. | Additional data on the effect of DOC on chronic toxicity of iron to marine species, to develop DOC adjustment for DGVs. | Moderate |
| Toxicant | DGV reliability | Reason for requiring further data | Additional research need | Priority* |
|---|---|---|---|---|
| Chlorine (marine) | Very high | There are no data for marine plants, although they are unlikely to be more sensitive than algae and, therefore, are also likely to be protected by the DGVs; however, further studies to confirm this are desirable. | Chronic toxicity tests of chlorine with marine plants. | Moderate-high |
| Nitrate (fresh) | High | Uncertainty and lack of data on the effect of true hardness and chloride on nitrate toxicity. This needs to be characterised to determine if the updated hardness-based DGVs are appropriate or require revision. | Additional studies to characterise the effects of true hardness (i.e. calcium and magnesium) and other potential toxicity modifying factors on nitrate toxicity. | Low |
| Toxicant | DGV reliability | Reason for requiring further data | Additional research need | Priority* |
|---|---|---|---|---|
| 2,4 D (marine) 3rd party | Low | Low reliability DGVs based on only 5 toxicity values for marine phototrophs. | Additional chronic toxicity tests of 2,4-D with marine phototrophic species (e.g., plants and algae). | High |
| Ametryn (fresh) 3rd party | High | Although classified as high reliability, the DGVs are based on only 8 toxicity values for freshwater phototrophs. | Additional chronic toxicity tests of ametryn with freshwater phototrophic species (e.g., plants and algae). | Low |
| Ametryn (marine) 3rd party | High | Although classified as high reliability, the DGVs are based on only 9 toxicity values for marine phototrophs. | Additional chronic toxicity tests of ametryn with marine phototrophic species (e.g., plants and algae). | Low |
| Metsulfuron-methyl (fresh) | Moderate | Insufficient chronic negligible effect toxicity data to meet the preferred dataset size; nevertheless, the final dataset comprised 8 chronic negligible effect toxicity values (7 phototrophs and one heterotroph). | Additional chronic toxicity tests of metsulfuron-methyl with phototrophic (e.g., plants and algae) freshwater species. | Moderate |
| MCPA (marine) 3rd party | Low | Of the 26 phototroph toxicity values used to derive the DGVs, only 3 were based on chronic toxicity to marine species. | Additional chronic toxicity tests of MCPA with marine phototrophic species (e.g., plants and algae). | High |
| Paraquat (fresh) | Moderate | There is some, albeit limited, evidence that hardness can affect the toxicity of paraquat. | Further investigation into the comparative toxicity of paraquat with varying concentrations of cations would be required to determine if or how to incorporate water hardness into the DGV derivation. | Low |
| Simazine (marine) | Moderate | Of the 15 toxicity values used to derive the DGVs, 8 were based on chronic negligible effect data while a further three were based on chronic EC50 data; the remainder were based on acute toxicity. | Additional chronic toxicity tests of simazine to both phototrophic and heterotrophic marine species. | Low |
| Sulfometuron-methyl (fresh) | Unknown | Insufficient data to derive a DGV using the SSD method, so the assessment factor method had to be used; this results in highly uncertain DGVs that are classified as having “unknown” reliability. | Additional chronic toxicity data for freshwater phototrophic species (e.g., plants and algae). | High |
| Toxicant | DGV reliability | Reason for requiring further data | Additional research need | Priority* |
|---|---|---|---|---|
| Fipronil (marine) 3rd party | Moderate | Of the 24 toxicity values used to derive the DGVs, only 2 were for marine species; the remainder were for freshwater species. | Additional chronic toxicity tests of fipronil with marine arthropod species (being the key sensitive taxonomic group) | Moderate |
* The current priority status is not formal and has been based on: (i) the current reliability of the DGVs (e.g., low reliability DGVs get higher priority to help bring them up to a higher reliability rating); (ii) the number of toxicity values in the derivation; and (iii) general knowledge of which issues are likely more important than others (e.g. although the nitrate DGVs are high reliability, there is outstanding uncertainty over several issues that are very important to address). A formal priority status may be formalised in the future in conjunction with the ANZ Guidelines committees.
