Nullinga Dam analysis released

02 August 2019

Building Queensland has released the Nullinga Dam and Mareeba Dimbulah Water Supply Scheme Improvements Detailed Business Case. Developed in partnership with Sunwater, the business case provides a robust assessment of the opportunities and challenges of increasing water available for agricultural activities in support of potential future demand in the Mareeba Dimbulah Water Supply Scheme.

The business case investigated improving the Mareeba Dimbulah Water Supply Scheme rules and operation, and upgrading the existing Arriga and East Barron Channels. An in-depth demand assessment was undertaken along with analysis of the design and construction of Nullinga Dam.

The business case analysis reveals construction of the proposed Nullinga Dam is neither financially or economically viable. The proposed Nullinga Dam site is located in a poor performing catchment requiring a costly build solution. To construct a dam that would meet identified demand would require an extended and costly construction program relative to the volume of water that would be available.

There is an opportunity to support expanded agricultural production in the area; however, only at a price that is substantially lower than the actual cost per megalitre of delivering additional water. Full cost recovery pricing models that align with the current Queensland and Commonwealth Government water pricing policies are not commercially viable. A full cost recovery charging approach would result in $15,900 per megalitre for Medium Priority water allocations—considerably higher than the willingness to pay for current customers in the Mareeba Dimbulah Water Supply Scheme.

The long-term water supply needs of the Cairns region were assessed in detail as part of the business case, and the outcomes of this analysis indicate that the Cairns region does not require a new water supply source for at least the next 40 years.

The detailed business case was completed in June 2019. It has been made publicly available to inform stakeholders and the community of the analysis underpinning the outcomes.

View the Nullinga Dam and Mareeba Dimbulah Water Supply Scheme Detailed Business Case.

Building Queensland to integrate with government

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  The Queensland Government has announced it is integrating Building Queensland with the Department of State Development, Infrastructure, Local Government and Planning. This reform will mean a change in functional focus from leading the preparation of business cases on behalf of government agencies and identifying infrastructure priorities, to assisting agencies to progress infrastructure proposals including […]


Business Case Development Framework – Release 3 now available

20 April 2020

Building Queensland Business Case Development Framework – Release 3 is now available. Our Business Case Development Framework has been guiding the development of the state’s infrastructure proposals since 2016. It has helped bring about  a consistent and rigorous approach to proposal development – enabling decision-makers to compare investment opportunities. While a significant focus of the update has been […]


Paradise Dam Options Assessment released

25 March 2020

Building Queensland has today released a report assessing the long-term options for Paradise Dam. The Paradise Dam Options Assessment responds to the Queensland Government’s request for Building Queensland to assess long-term options to ensure water security for future economic growth and to maintain community safety. Released this morning during a teleconference with the Minister for Natural Resources, Mines […]