Adaptive water management in response to climate change: the case of the southern Murray-Darling Basin

ABSTRACT

For over two decades, Australia has sought to address the effects of the over allocation of water resources in the Murray-Darling Basin through implementation of the Murray Darling Basin Plan (2012). It is increasingly apparent that the impacts of climate change on surface runoff and water demand will profoundly impact rivers, potentially negating the Basin Plan’s achievements. It will be critical that we use the lessons from the last two decades to inform adaptation to climate change. Environmental water allocations over the last decade have focussed on providing base flows, freshes, and overbank flows, within a Natural Flow Regime paradigm. In a climate-changed world managers have three broad options. The first would be to continue to pursue single loop adaptive management making improvements within the existing framework. The second option would be to adapt the system approach to focus on a subset of sites, akin to maintaining aquatic reserves. The third option would be to move flow management away from the natural flow paradigm to a more functional regime. This approach would invoke the second adaptive management loop by evaluating options for adaptation and developing processes for navigating trade-offs among social, economic, cultural, and environmental values and between protection, restoration, and adaptation. Changes in water availability because of climate change will require more than incremental adaptation (first loop adaptive management) and will necessitate consideration of either protecting a smaller suite of spatial areas or a smaller set of functional outcomes. This requires profound change to some of the Basin Plan’s approaches to environmental flow management. The review of the Basin Plan in 2026 provides a rare opportunity to adapt the Basin Plan from a foundation of protect and restore to one that includes adaptation, and this will require substantive changes to the Basin Plan (second loop adaptive management).

KEYWORDS:

• Environmental flow
• restoration
• planning
• adaptive management

Acknowledgements

The authors would like to thank the many collaborators we have worked with in seeking to inform implementation of the Plan. We would also like to thank Barry Hart for his stewardship of this special issue and his patience.

Disclosure statement

The authors undertook this work as part of, or in addition to, their professional responsibilities. The work was not supported by any external funding and the authors are not aware of any conflicts of interest.

Additional information

Notes on contributors

Ben Gawne

Ben Gawne’s background is as a freshwater ecologist with extensive experience generating, synthesising and communicating knowledge to support the adaptive management of water resources. For over 25 years Ben has collaborated in the planning, implementation and evaluation of significant river restoration initiatives including the Living Murray and the Basin Plan. Ben’s experience and breadth of knowledge on ecosystem responses to both water resource development and flow restoration have given him an understanding of the complexity and challenges associated with sustaining multiple values in a contested environment. Through both collaborative research and advising water managers, Ben engages to find ways of clarifying the objectives and then ways of representing the system or expected management response in ways that support adaptive management, reporting and communication objectives.

Ross Thompson

Professor Ross Thompson is Director of the Centre for Applied Water Science and co-Director of the Institute for Applied Ecology at the University of Canberra. Ross is a freshwater ecologist with interests in the study of biodiversity and the restoration of landscapes. His fundamental research is in food web ecology; seeking the rules that determine how natural communities assemble and persist. His applied research addresses the ways in which food webs can be influenced by anthropogenic factors including urbanisation, land clearance, pharmaceutical contamination, river flow diversion and restoration, and invasion. He has an active research program on aquatic biodiversity and ecosystem function in urban and rural landscapes. Ross has published more than 100 papers, 10 book chapters and more than 200 scientific reports. He has sat on the Australian Research Council College of Experts and has recently stepped down from the NZ Marsden Panel. His work has strong links to government and industry, and Ross sits on a number of senior technical advisory panels for local, state and federal research programs.