Brisbane river catchment flood study

The Flood Study provides a comprehensive analysis of a range of flood events that may occur within the Brisbane River catchment and is a critical first step toward developing a Strategic Floodplain Management Plan for the region.

The Flood Study area includes parts of the Brisbane River catchment, with a focus on flooding events downstream of Wivenhoe Dam including the Brisbane River, Lockyer Creek and the Bremer River system.

Two major components of the Flood Study are the hydrologic and hydraulic assessments.

• The hydrologic assessment investigated how combinations of rainfall, dam levels, ground conditions and tide influences could merge to create potential floods events within the floodplain. This assessment considered the entire Brisbane River catchment (including the Lockyer Valley and other regions outside of the Brisbane River floodplain).
• The hydraulic assessment used the data inputs from the hydrology assessment to model how floodwaters progressed through the Brisbane River floodplain, taking into account terrain characteristics of rivers, creeks and floodplains, and infrastructure such as bridges, stormwater networks, dams and levees. The hydraulic assessment generated flood modelling for the lower Brisbane River downstream of Wivenhoe Dam.

The overview provides a non-technical summary about how the Flood Study was carried out and how this information will help to improve community safety and resilience to flooding in the future.