Macquarie-Wambuul Water Security Project

The proposed Macquarie-Wambuul Water Security Project aims to improve water security and reliability and support a healthy river environment.

To achieve these aims, the department’s Water Group investigated options aligned with the Macquarie-Castlereagh Regional Water Strategy.

These included:

• a regional pipeline connecting Dubbo to Nyngan and other towns
• using some of Burrendong Dam’s flood mitigation zone to increase water storage
• a new weir to potentially replace Gin Gin Weir located between Warren and Narromine
• other options identified in the regional water strategy, including consideration of accessing groundwater during a drought.

For more information about the Macquarie Wambuul Water Security Project, download the March 2026 fact sheet (PDF, 174 KB).

Project location

The Macquarie-Wambuul River system is part of the Macquarie-Castlereagh catchment in central west NSW, within the traditional lands of the Gomeroi/Kamilaroi, Ngemba, Ngiyampaa, Wailwan and Wiradjuri people.

The river flows from the Great Dividing Range near Bathurst, north-west past Wellington, Dubbo, Narromine and Warren to meet the Barwon River upstream of Brewarrina. It includes the Macquarie Marshes, an internationally significant wetlands area.

Project timeline

The Macquarie-Castlereagh region is experiencing more frequent and severe drought, increasing pressures on water security. There is a need to:

• improve town water security in the region
• deliver water more efficiently to high priority needs
• maintain environmental flows in the system, including to the Macquarie Marshes
• improve the drought resilience of industry, including meat processing and agriculture.

The Central West is one step closer to improved water security, with a preferred option for the Macquarie–Wambuul Water Security Project locked in to progress to the next phase.

It follows the thorough assessment of four possible solutions to shore up water supplies in the catchment and to support a healthy river system, particularly for the Macquarie Marshes.

Coming out on top as the most viable option to boost drought resilience for the region is to enable Dubbo Regional Council to increase its access to groundwater when Burrendong Dam reaches a critically low level. 

This would improve water reliability for the town, greatly reduce reliance on the dam and free up surface water for nearby communities such as Nyngan and Cobar. 

Work is currently underway to further assess the viability of this option, including what infrastructure will be required and to assess regulatory pathways including:

• Infrastructure investigations – assessing what new infrastructure may be required, such as expanding the bore network south of Dubbo and constructing a pipeline connecting to the water treatment plant. This work ensures groundwater can be accessed at the scale needed during extreme drought conditions.
• Licensing and regulatory assessments – examining how temporary access to additional groundwater could operate during extreme events, including the rules and approvals designed to safeguard the aquifer and ensure any potential effects on other groundwater users are appropriately managed.

These will be assessed in the Full Business Case to understand their economic, social and environmental costs and benefits to help inform future government funding decisions.

Project funding

The NSW and Australian Governments are jointly funding $9.35 million to deliver a final business case for the project, with the Australian Government contributing through the National Water Grid Fund.

The funding will allow the NSW Government to deliver a focussed options analysis. Detailed technical studies will include economic, engineering, cultural heritage and environmental assessments. The  Water Group will oversee this analysis and integrate stakeholder consultation to ensure the best infrastructure solutions are identified and progressed.

The outcomes of these studies and consultations will be included in the final business case, which will guide future funding decisions for the project by the NSW and Australian Governments. We are aiming to complete the full business case by mid 2026.

Stakeholder engagement

We are committed to building and maintaining respectful, trusted and collaborative relationships with our communities and stakeholders to ensure water infrastructure projects achieve the best possible outcomes.

We will be offering opportunities for communities and stakeholders, including First Nations communities, to engage with us and provide feedback as we develop the final business case for the project.

Upcoming engagement opportunities will be highlighted on this project webpage and on the Water Group’s have your say page.

A What we heard report capturing feedback from community engagement between 2024 and 2026 is now available. 

The report outlines responses from key stakeholders, First Nations groups and the broader community to the four options being explored as part of preparing the Full Business Case.

The report includes: 

• an overview of the engagement process and participation by community and stakeholders
• a summary of what we heard on key options proposed and our responses to the feedback received.
   

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