How can management of uncertainty in sustainable diversion limits be advanced in the review of the Murray-Darling Basin Plan?

ABSTRACT

This paper explores how scientific uncertainty was addressed in the Australian Government’s decision-making process leading to the establishment of the ‘sustainable diversion limit’ (SDL) for the Murray-Darling Basin Plan in 2012. Our research draws on a systematic document analysis to generate an argument map representing the reasoning presented in government reports and legislation, as well as interviews with current and former public servants and researchers who have knowledge of the decision-making process. Looking towards the review of the Basin Plan, this analysis provides additional evidence for a number of areas to be discussed to advance the management of uncertainty in the associated decision-making. First, there is a need to address the challenges to adaptive management, as adaptive management delegates much of the uncertainty to future changes in policy as improved knowledge is gained. Second, there is a need to generate and use new knowledge for the review since the legislative mandate to use the ‘best available science’ enabled the use of pre-existing models and historical climate data. Third, there is a need for dialogue on handling of trade-offs between objectives given that uncertainty creates space for political pressures from interest groups. Fourth, there should be wider transparency about uncertainty in decision-making processes.

KEYWORDS:

• Murray-Darling Basin
• uncertainty
• sustainable diversion limit

Acknowledgements

We thank the interview participants for their contributions. We thank four anonymous reviewers for their useful input in improving the paper.

Declaration of interest statement

The authors report there are no competing interests to declare.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The work was supported by the Australian Research Council [DE190100317]; Australian Research Council [DE2001922].

Notes on contributors

Leila H. Noble

Leila Noble is a PhD candidate at ANU’s Fenner School of Environment and Society and Institute for Water Futures. She is interested in how to sustainably manage water resources to meet multiple needs under uncertainty and climate change.

Joseph H.A. Guillaume

Joseph Guillaume is a Fellow at the Fenner School of Environment and Society and Institute for Water Futures, ANU. He specialises in uncertainty management in decision support, with a particular focus on water resources and the use of integrated modelling.

Carina Wyborn

Carina Wyborn is an Associate Professor with the ANU’s Institute for Water Futures and Fenner School of Environment and Society. She is an interdisciplinary social scientist with background in science and technology studies, and human ecology. Carina’s research examines how land and water managers make decisions about future environmental change, focusing on the intersection of science, politics, policy, and practice. She currently holds an ARC Discovery Early Career Research Award, which involves research on foresight practices and anticipatory governance to identify methods that enable diverse actors to negotiate shared pathways for water reform in the Murray Darling Basin.

Anthony J. Jakeman

Tony Jakeman is Emeritus Professor with the ANU’s Institute for Water Futures and Fenner School of Environment and Society. He is an interdisciplinary scientist with background in computational mathematics and modelling. He has long-term experience in integrated assessment and modelling with most focus on water resource systems and hydrology.