New National Benchmark for Floodplain Management

Following widespread flooding across Queensland in 2010 and 2011, the Queensland Floods Commission of Inquiry was established to assess the management of floods across the state, including the processes undertaken by government agencies to prepare and plan for floods.

One of the key recommendations from the Inquiry was that Councils should develop comprehensive floodplain management plans, including in the Brisbane River floodplain where 14,000 properties were inundated in 2011. The first stage of this process was the development of hydrologic and hydraulic models, delivered by Aurecon and BMT respectively as part of the Brisbane River Catchment Flood Study. Following that study, the Queensland Government appointed us to prepare the Brisbane River Strategic Floodplain Management Plan; a comprehensive roadmap to guide floodplain management in the lower catchment.

State Government Minister, Cameron Dick has described as “a new national benchmark for floodplain management”.

After 18 months of intensive effort from our team, project partners, client and stakeholders, the Strategic Plan has recently been released.  The Strategic Plan helps stakeholders and the community better understand current and future flood risks and identifies regionally consistent approaches to strengthen flood resilience across the lower Brisbane River floodplain. Key deliverables from the study include: 

• A full ISO:3001 compliant risk assessment including integrated hydraulic risk mapping across the full extent of the floodplain, exposure and community vulnerability assessments
• Community vulnerability mapping across a range of key socio-economic indicators
•  Flood damages estimation using new flood damage curves developed for the study and informed by floor level survey of 130,000 buildings in the floodplain
• Hydraulic assessment of various structural modification measures including levees, flood gates, temporary barriers and flood mitigation dams
• Development of a community resilience framework informed by extensive research and community input, which translates regionally-specific resilience aspirations to tangible actions for stakeholders and the community
• Risk-based land use planning guidance, providing direction to support a consistent approach across all four councils in the study area
• Evacuation assessment, including time of inundation information derived from hydraulic models using 11,340 different combinations of catchment and flood conditions
• Property-specific flood risk data linking floor levels to stream gauge levels to enable residents to translate flood warnings to personal risk

The Strategic Plan identifies 52 actions that guide how the Queensland and local governments will work together to better manage flood risk now and into the future. In addition, 17 of those actions have state-wide application to support the flood resilience of all Queensland communities.

Our flood modelling expertise began in our Brisbane office more than 40 years ago and has since been applied across Australia and internationally.

Discover more about our environment capabilities available here