Banana Shire Flood Study
Taroom Township is located significantly higher than the surrounding Dawson River floodplain to the west of the town. Flooding at Taroom is impacted by the Leichhardt Highway crossing of the Dawson River. The town is mainly flood free.
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
1% chance of occurring each year or 1% AEP
Approximately 1 in 100 year event
1% AEP event Climate Change (CC) sensitivity simulation or 1% + CC AEP
Approximately 1 in 100 year event - adjusted for climate change sensitivity
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.
Considering the information above, the proposed area of investigation to protect residents from the impact of flooding is shown below.
Image: Proposed area of investigation with 1% + CC AEP flood inundation depths shown
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.
Flood inundation in Taroom is primarily governed by flows from the upstream catchment and to some degree, the Leichhardt Highway crossing of the Dawson River. As a result, there are only a small number of feasible structural measures that could be implemented to reduce the flood risk of the proposed area of investigation. This area is shown in the image above.
The structural measures identified that may reduce flood risk within the proposed area of investigation include:
- Low levees, large levees or a combination of both to provide some level of flood protection to residents
- Individual property levees
- Raising of existing stumped houses.
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 4, 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 firstname.lastname@example.org or by mail at Reply Paid GPO BOX 633, Brisbane QLD 4001.