Managing salinity risks in the NSW Murray-Darling Basin catchments

The threat of salinity across the Murray-Darling Basin poses significant economic, environmental and social challenges for NSW but also for the other jurisdictions that share this important resource. The effect of a fluctuating climate and changing land and water use mean salinity will continue to be a serious risk across the Basin catchments without careful and consistent management.

In this project, RMCG worked with the NSW Department of Climate Change, Energy, the Environment and Water (DCCEEW) to understand and assess the risk of salinity in each of the Murray-Darling Basin catchments throughout the state.

The project developed desktop risk assessments, supported by the expertise of internal and external stakeholders familiar with the soils, climate, hydro-geology and land management practices contributing to salinity risks in these catchments.

“In partnership with Greg Holland from Feehan Consulting, we contributed knowledge of the natural systems, waterways and landscapes of NSW and expertise in salinity management, targets and reporting for the Murray-Darling Basin,” RMCG Senior Consultant and project manager Joanne Thom said.

The Basin Salinity Management Program

The Basin Salinity Management Program is responsible for monitoring and preventing salinity in the Murray River from exceeding acceptable levels, through partnerships which help enforce these targets.

Our team developed a risk assessment approach to identify catchments posing the greatest potential salinity risks to the Murray and Darling Rivers and local values including ecology, agriculture, drinking water and infrastructure.

Our approach

A contemporary summary of catchment conditions was developed which documented the landscape, land use, hydro-geological and climatic risk factors which were likely to contribute to the risk of salinity occurring in the catchments, ranking the likelihood and consequence of each. From here, a risk rating was applied to each catchment identifying where salinity risk was high and further investigations were recommended.

The risk assessment contributes to meeting the objectives of the Basin Salinity Management 2030 strategy and the requirements of the Murray-Darling Basin Agreement.

Before the catchment assessments were rolled out, our team prepared a pilot approach to standardise the structure and content of the catchment summary and to test the risk rating methodology with DCCEEW.

The approach was shared with subject matter experts and local knowledge holders via targeted group interviews to gain insights and improve understanding and management of salinity risk in the state’s inland catchments, using the analysis to inform decision making.

“The depth and breadth of knowledge and expertise among industry experts, internal and external to DCCEEW, was important to harness through consultation in this project to ensure the desktop risk assessments reflected the best available knowledge,” Joanne said.

Reviewing, monitoring, mitigation and learnings

Based on the initial results of the salinity risk assessment and using the risk ratings, future detailed investigations will be developed to assist in evaluating and improving the current monitoring framework and identifying priority areas for management.

The development of salinity profiles for NSW’s Murray-Darling Basin catchments builds on RMCG’s previous work with Victoria (DEECA), conducting risk assessments for Murray River catchments.

“The work with DEECA in Victoria and now this work with DCCEEW in NSW, sees a consistent methodology being applied to the identified risk of salinity as a threat to the rivers in the Basin,” Joanne said.

“This was an important piece of work for RMCG to be involved in as it built on an approach that we did for the Murray-Darling Basin catchments in Victoria.”

Barwon River at Mungindi.