Burdekin Falls Dam Raising Project – FAQ

The Burdekin Falls Dam Raising Project proposes to raise the existing dam by two metres to increase water supply and support future water demand in the Burdekin and surrounding regions. The project will also:

• increase the dam’s resilience to extreme weather events
• bring the dam in line with modern engineering design standards
• ensure the dam meets the safety requirements set out in the Water Supply (Safety and Reliability) Act 2008 (Qld).

The proposed works would include raising the spillway and the abutments (sides of the spillway) using concrete buttressing; raising and widening the saddle dams surrounding Lake Dalrymple; and constructing a new saddle dam on the right bank.

Although Burdekin Falls Dam continues to operate as it should, improvement works must be undertaken to bring the dam in line with modern engineering design and safety standards. The proposed dam raising provides an opportunity to increase water supply in the region and deliver the required safety upgrades to improve the dam’s resilience to pass significant floods in the future.

An independent assessment has demonstrated that projected demand could exceed current yield in 2031, and that a raising of two metres would meet this demand and provide for future needs.

The project would create hundreds of jobs during construction and deliver considerable benefits to North Queensland. Further detail is available in this fact sheet.

Raising Burdekin Falls Dam by two metres would increase the storage capacity by 574,240 ML or 31 per cent. This would increase the availability of medium priority water by approximately 150,000 ML per annum.

A comprehensive forecast of future water demand to 2050 was undertaken to inform the potential raising height. The assessment focused on the Burdekin Basin catchment and current Burdekin-Haughton Water Supply Scheme including adjacent areas with the potential to supply water in the future. The demand assessment involved a combination of primary desktop research, drawing on past studies and investigations, consultation with urban, agricultural, and industrial water users, and econometric modelling. It also considered the potential impact climate change could have on demand, particularly in the agricultural sector, and changes in rainfall and temperature based on weighted average estimates from the Queensland Future Climate Change Datasets. Further detail on the future water demand will be made available in the environmental impact statement.

There is long-term demand for water in the Burdekin region and an independent assessment found a raise of two metres will address demand under all scenarios. It is the most efficient option to ensure the water security needed to underpin agriculture, industry, urban water supply, or new and emerging industries, such as hydrogen. Compared to other height options, a two-metre raise will have minimal environmental, social and cultural heritage impacts, while also providing an opportunity for significant cost savings. A two-metre raise also provides the resilience needed to meet dam safety requirements. Sunwater owns more than 98 per cent of the additional land required for a two-metre raise and, unlike other height options, it is in line with the strategic reserve volume currently allocated with the Burdekin Basin Water Plan.

Burdekin Falls Dam needs to be upgraded to meet dam safety requirements. The Queensland Government and the Australian National Committee on Large Dams Inc (ANCOLD) have set guidelines for referrable dams. Sunwater (and other referable dam owners) are required to progressively complete works on dams which require upgrades by 2035.

Although Burdekin Falls Dam continues to operate as it should, improvement works must be undertaken to ensure compliance with these standards. A comprehensive risk assessment (CRA) identified actions needed to bring the dam in line with modern engineering design and safety standards.

Irrespective of whether a raising is approved, safety improvement works will need to proceed.

As there is an opportunity to deliver the dam improvement and raising projects simultaneously, at significantly reduced construction costs, both options were assessed in the detailed business case.   

The Queensland Government requires preparation of a detailed business case for infrastructure projects of $100 million or more which may impact on Queensland’s economic growth and social outcomes. As Sunwater is a Government Owned Corporation, the detailed business case aligns with the Queensland Government’s Business Case Development Framework.

The detailed business case outlined options to increase the dam’s water supply and long-term viability and reviewed the social, environmental, economic, and financial feasibility of the projects. It considered:

• Stand-alone dam improvement project.
• Combined dam improvement with a potential raising.
• Stand-alone dam improvement following by a dam raising at a future date.

The proposed dam raising requires an environmental impact statement (EIS). The EIS will describe and assess:

• the current environment around the project
• potential environmental, economic and social impacts and benefits of the project
• the proposals being put forward to avoid, minimise, mitigate and/or offset potential impacts.

Sunwater is currently preparing a draft EIS that will involve public consultation. Further detail about the EIS process is available in this fact sheet.

Sunwater will prepare the EIS which will be submitted to the Office of the Coordinator General for adequacy review against the Terms of Reference. The public and State Government advisory agencies will have the opportunity to review and make submissions on the draft EIS in relation to the assessment of impacts and commitments.

The next stage of planning includes progressing design, selected cultural heritage surveys, collecting more detailed geotechnical information, procurement planning and consulting with key stakeholders and the community to progress the EIS.

Sunwater expects to submit a draft of the EIS to the Office of the Coordinator General in 2023. Community consultation has commenced, and further updates will be provided as the EIS progresses.

Upon completion of the EIS (if approved), the detailed business case will be revisited and, following a Queensland Government investment decision for the raising project, it is expected that the DBC will be publicly released.

Yes, the EIS will examine potential impacts both at the dam and around the proposed inundation area, as well as potential impacts resulting from changes to the water flow downstream of the dam.

The groundwater assessment team is working collaboratively with the flood hydrology, surface water resources, aquatic and terrestrial ecology teams to prepare a comprehensive assessment of potential changes to the groundwater environment in accordance with the EIS Terms of Reference. Further details on the EIS Terms of Reference is available here.

Burdekin Falls Dam is the largest water supply dam in Queensland. The current dam is a mass reinforced concrete dam surrounded by four earthfill saddle dam.

The main dam has a total length of 876 metres and consists of a spillway with right and left abutments.

Water releases are made from the dam to the river through outlet works (three radial gates) within the left abutment. 

Water from Burdekin Falls Dam supplies over 50,000 hectares of agriculture, groundwater recharge and aquifer management, supplementary urban water to the Townsville Local Government Area and coal mines in the Bowen Basin.