While irrigators, industries and communities across the Murray-Darling Basin wait with bated breath to discover what the next Basin Plan Review will deliver towards the end of this year, one thing is already certain: the Basin is continuing to get hotter, drier, and more challenging for those who depend upon its vital water.

In preparing for the possibility of tougher restrictions, shifting water demands, and higher water prices, it’s timely that some of One Basin’s initial projects – the Quickstart projects – are beginning to deliver powerful tools and processes to support the increasingly vital work of catchment managers, modellers, policymakers, and community engagement officers.

Recent months have seen the completion of two ‘Quickstarts’ tackling interrelated aspects of climate adaptation planning in some of the Southern Basin’s hardest-pressed catchments, with critical implications for water allocations and availability: sophisticated stress-test modelling of climate scenarios and their likely impacts on water availability; and the community and institutional relationships of Catchment Management Authorities – with vital lessons for communities struggling to be heard across the Basin.

Quickstart 4: Shifting water availability and demand – the implications of climate change

One of the earliest projects of One Basin CRC to get off the ground, Quickstart 4 provided a huge boost to the science of climate risk and water availability modelling in the Murray-Darling Basin – and a methodology that directly informed the critical Basin Outlook report released by the Murray-Darling Basin Authority (MDBA) at the end of November.

The project effectively delivered the most comprehensive ‘stress-test’ of water availability and river flows ever conducted in the Basin, combining thousands of climate scenarios to see how potential combinations of rainfall and temperature in different locations might impact flows and ecological ‘tipping points’ across the Basin. Veteran University of Melbourne water policy specialist Avril Horne and modeller Andrew John led a team that combined variable hydroclimate models with regression analyses and machine-learning emulators – enabling thousands of scenarios to be studied over broader catchments, and predicting their impacts on river flows, runoff, and water availability for irrigators and communities.

The project applied its basin-wide models to the impacts of different climate scenarios in the connected Southern Basin – including the Murrumbidgee and Goulburn rivers, which are facing bleak predictions of river flows contracting significantly over the next 25 years. Recent projections of ‘plausible’ changes in rainfall across the Southern Basin by between -8% and +5% portend damaging impacts on smaller rivers – including some, says Prof Horne, “where current environmental flows may not be able to resurrect these systems”.

The project also demonstrated the value of modellers working in close partnership with water authorities and irrigators, as a vital first step in developing informed adaptation strategies for a drier future. Ultimately, its stress-testing provided a relatively simple framework for quickly assessing climate risks at a basin scale, which will help the MDBA, governments and water authorities measure the efficacy of their allocation and adaptation strategies, help irrigators in their planning – and provide a strong foundation for One Basin’s Putting People at the Centre project, which aims to proactively involve communities in the science and planning of climate adaptation.

Horne says that, used in conjunction with site-specific modelling, the stress-test approach offers a powerful tool for planners working on water licences, environmental flows, and inter-valley transfers – with Basin-wide inflow data providing the potential for increasingly accurate predictions. “We see tiny changes in precipitation and temperature in the Southern Basin having dramatically different impacts in Victoria and New South Wales, where some systems exhibit steadier declines,” she says. “Having federally funded research through One Basin makes our findings much more accessible and transferrable, which will be a big legacy of this CRC.”

Joel Bailey, the MDBA’s General Manager of Applied Science, says the project not only helped his team develop their technical capabilities and provided “a new line of evidence” to inform their Basin Outlook – and in turn the Basin Plan Review – but cemented a powerful partnership between the Authority and Professor Horne’s team.

“Climate change is often presented as a choice between denial and despair, which we think is a false dichotomy,” says Bailey. “The Basin’s climate has been changing for decades, and while the challenges are significant, there is still hope for well-informed, effective and orderly adaptation, particularly given the highly engaged and knowledgeable stakeholders across the Basin.” 

Bailey notes that the MDBA routinely applies multiple lines of evidence in its assessments. “Avril and her team were very accommodating in terms of providing data and commentary to the authors of the Basin Outlook, adding to the information already generated by our Sustainable Yields study. A lot of what we found in this study and the Quickstart project I would describe as sobering but not surprising. Temperatures have been and will continue to rise steadily, while uncertainty remains around how those changes translate into rainfall and river flows.

“The models of the Quickstart project are a really nice addition to our toolbox, alongside our more detailed higher-resolution models, because they can be run and adjusted more quickly – they’re more agile, so they can help target where our more sophisticated, resource-intensive models are best applied, which is critical given reporting timelines and practical constraints. There’s a finite number of applications our detailed models can be used for… but with these new models, many more permutations can be run, because they have fewer nodes and are orders of magnitude less complicated.”

Bailey says the uniquely collaborative nature of the One Basin network will enable the MDBA and Melbourne University to continue sharing data and expertise long into the future. “Our relationship is stronger now, we talk regularly with Avril and her team, which engages our staff in broader research across the basin, and helps us see a more sophisticated picture of what’s going on. This project not only helped us to build our capabilities but to kickstart vital strategic conversations, which all add layers of depth to our relationship.”

Quickstart 10: Building capacity to adapt to a more variable water future

The second Quickstart project to wrap up in 2025 laid some vital foundations for regional communities and water authorities – in this case the North East CMA and the Goulburn Broken CMA – to build more effective and transparent partnerships for regional adaptation planning, as well as stronger relationships with state and federal agencies.

The project began with an eye-opening study that confirmed widespread disillusion among communities that neither their values and priorities for rivers – for urban water, employment, recreation, cultural connections – nor their greatest concerns – water quality, agriculture, livestock, rare species – are adequately reflected in decision-making or policy documents. In the North East and Goulburn Broken catchments – where 5% of the Basin’s land contributes nearly 50% of its water – these values stand in stark contrast to decisions that often seem foisted on communities by faraway bureaucrats. “There’s a distinction between their local managers and the people who write policy,” notes Madeline Grupper, who conducted some of the early research. “Their local managers might have their backs, but not have a lot of power to do things they want – but the politicians have the power but not necessarily the will.”

Prof Horne said that people’s relationships with rivers are often informed by their lifestyles and interactions, “whereas policy documents describe discrete and compartmentalised values, which people find harder to relate to”. “The MDBA and Victorian CMAs tend to put values in ‘buckets’ that don’t always resonate with people,” notes Horne. “It shouldn’t be a ‘zero sum game’ between the environment and the economy… If you ask people about specific values like fish or a particular industry, it doesn’t tell you much about a water-constrained future – it’s the wrong question to ask. When you talk about equity, on the other hand, people start to reflect on the workings of a large, interconnected system. These are the important things that should be driving future policies – this had a big impact for the CMAs.”

For Goulburn Broken CMA, currently preparing its next Regional Waterway Strategy, the discussion could not have come at a more propitious time. “It was a great launchpad, which helped us refine our methodology for putting people at the centre of the climate-focused discussions informing our strategy,” says the CMA’s River and Wetland Health Program Manager, Simon Cowan.

Cowan, who’s leading the development of the 10-year strategy, says the opportunity to interview a broad cross-section of the community – “plus the inputs of some really smart researchers” – enabled the CMA to develop more sophisticated ways of canvassing community opinions. “We’re not going out with a recipe book of stock questions and preordained goals anymore,” he says. “Rather than focus upfront on our priorities, we’re being far more deliberate and thoughtful in finding out what people really think… plus we’re asking for people’s inputs much earlier in the process.”

“In the past, with our conversations about climate risks with the community, with DEECA (Victoria’s Department of Environment) and the MDBA, it was clear we were all looking at the same changes in the landscape but focusing on different priorities,” adds Goulburn Broken CMA CEO Carl Walters. “Since One Basin came along, it’s given us an opportunity to look at how we can get onto the same page – with no one fearing being left behind. I know they said that 15 years ago with the first Basin Plan, but it didn’t necessarily happen… Our role is to try and help our community have an informed discussion with the technocrats – and help governments connect with the people who have the most skin in the game.”

Like many CMAs, Cowan and Walters recognise the gaps between institutional and community priorities, and are passionate about bridging them. “History’s littered with poor decision-making processes,” says Walters. “It’s critical to start conversations with the community earlier, with no preconceptions about outcomes, and trust the community. They rarely let you down.”

As a result of the Quickstart project, Goulburn Broken CMA is refining a new values framework which will feed into core aspects of its Waterway Strategy. “We have a real opportunity to do deep, impactful work on what people care about and how they perceive their role in waterways’ management – and marrying this up with the views of the Yorta Yorta and Taungurung people as Traditional Owners, who hold such vital knowledge and connections to our waterways,” says Cowan. “Whether it’s restocking native fish or managing blackwater events, it’s becoming clearer that the catchment is under pressure. People can see the connected elements of what climate change is bringing, rather than just isolated changes.”

Cowan says the CMA regards itself as a “a conduit and a bridge” between the Victorian Government, the MDBA, and communities. “We’re not the only decision-makers, but we are a key part of the process, and we need to arm people with the information and processes to convey their concerns and priorities to those who can make a difference.” He believes the stronger community voice in their Waterway Strategy will be “an important example for the federal government and the MDBA”, and sees opportunities to share their new modus operandi with Victoria’s other CMAs though the Vic Catchments Forum.

Quickstart 10 also conducted interviews with the key institutions delivering water management policies in Victoria – DEECA, the MDBA, and the Victorian and Commonwealth Environmental Water Holders – which revealed clear discrepancies between how these agencies view the roles of CMAs in relation to climate adaptation, and the CMAs’ own views. “The CMAs are set up to perform legislative tasks under a project-based funding model, which is not well suited to climate change work,” explains Horne. “The CMAs felt they don’t have enough decision-making power when it comes to climate change – a finding that will enable them to have more structured conversations with DEECA, MDBA and CEWH, and help them build their influence to advocate for their regions.”

Both of the Quickstart projects will also feed into One Basin’s Putting People at the Centre project, which Prof Horne is leading with Adelaide University’s Holger Maier, in partnership with the MDBA and the Victorian CMAs. This project aims to develop a series of assessment tools to help water users analyse long-term climate scenarios in their localities, ‘stress test’ different aspects of their water use practices, and identify potential adaptation strategies – all in close collaboration with communities and water users.

More information:

To learn more about Quickstart 4: Shifting water availability and demand – the implications of climate change, please visit the project page (including links to publications and other resources), and watch a webinar presented by the project team.

To learn more about Quickstart 10: Building capacity to adapt to a more variable water future, please visit the project page (including links to publications and other resources), and watch a webinar presented by the project team.