Flood Mitigation Study — Western Brisbane

2D hydrodynamic flood study for a western Brisbane catchment, informing council's flood overlay update and identifying cost-effective mitigation options.

The Challenge

The existing 1D model was outdated and unable to accurately represent overland flow paths across the urban catchment. Council needed a defensible, 2D model to support planning scheme updates.

Our Solution

We built a TUFLOW 2D hydrodynamic model of the 850 ha catchment, validated against 2011 and 2022 flood events. Four mitigation options were assessed, with a staged detention basin approach recommended as the most cost-effective solution.

Outcomes

• Model accepted by council and State Government reviewers
• Mitigation option reduced Q100 flood levels by 0.35 m for 1,200 properties
• Report used to support a $6M council capital works programme

Services Delivered