Banana Shire Flood Study

BARALABA

Historic flooding

Flooding in the Dawson River at Baralaba is controlled by the Neville-Hewiit Weir located at the town and the Baralaba anabranch weir located approximately 1.7km upstream. The anabranch directs water to the north-west around Baralaba Mine, rejoining the main channel 5km downstream of the Neville-Hewitt Weir.

Extent of flooding

The below table explains the multiple Annual Exceedance Probability (AEP) flood events analysed as part of the Study. AEP indicates the probability of a flood event occurring each year expressed as a percentage. Flood probability can also be expressed as an Annual Recurrence Interval (ARI).

Annual Exceedance Probability, AEP

Approximate Annual Recurrence Interval, ARI

Impact on Township

5% chance of occurring each year or 5% AEP

Approximately 1 in 20 year event

  • Access to Baralaba across the Dawson River is severed

1% chance of occurring each year or 1% AEP

Approximately 1 in 100 year event

  • Lower part of Baralaba State School vulnerable to flooding

1% AEP event Climate Change (CC) sensitivity simulation or 1% + CC AEP

Approximately 1 in 100 year event - adjusted for climate change sensitivity

  • Identified in image below

 

A Probable Maximum Flood (PMF) event is the largest flood event that could occur at any given location. It is usually an estimated rainfall depth calculated using a range of methods and patterns.

  • Baralaba Hall and evacuation centre remains flood immune up to the PMF event

 

Considering the information above, direct structural measures are not being investigated in any areas within Baralaba. An inundation map for the 1% + CC AEP event is shown below.

Image: Potential upstream structural mitigation option (Baralaba) with Existing 1% + CC AEP flood inundation depths shown

*The Nathan Dam and Pipelines Project is considered to be one of the best long-term solutions for the provision of reliable water supplies to the Dawson-Callide and Surat Basin areas of Queensland. This project is a major initiative, however it does not yet have business case or funding approval. It has been included as a flood mitigation measure because it is a plausible long-term, regional scale option that could provide flood benefits to the town of Baralaba.

 

Potential flood mitigation options

Flood mitigation strategies are aimed at reducing residual risk, improving safety, minimising damage by reducing peak flood levels and depths, improving warning times and reducing flow velocities. This can be achieved through both structural and non-structural measures.

Some non-structural measures already form part of Council’s current Local Disaster Management Plan and Planning Scheme. After the completion of the Floodplain Management Plan, additional measures and updates to Council’s plans and schemes may occur.

A portion of the Baralaba State School site is the only property currently at risk from flooding within the Township. Therefore, direct structural measures are not being investigated in any areas within Baralaba.

 

Submit your feedback

Community feedback is a vital tool when analysing the viability and acceptance of proposed areas of investigation. To submit your feedback, please fill out the survey by clicking on the link below.

When answering Question 3, please rate your most preferred option as 1, your second most preferred option as 2, your third option as 3, and least preferred option as 4.

Surveys can be downloaded and submitted by email at floodstudies@kbr.com or by mail at Reply Paid GPO BOX 633, Brisbane QLD 4001.

 

Survey for Baralaba