This dataset, created in June 2013, provides an indication of the likelihood of a flood occurring from Brisbane River inside the Brisbane City Council local government area. This layer contributes to the overall Flood Awareness Mapping for Brisbane City Council.
River flooding happens when widespread, prolonged rainfall occurs over the catchment of a river. As the river reaches capacity, excess water flows over its banks, causing flooding. River flooding can occur hours after the rain has finished, depending on the location within the catchment. The extent of river flooding depends on the severity of the weather and the capacity of the river among other things. The impact on a home depends on how close it is to the river and the proximity to low lying areas.
There are four different river flooding likelihood areas in Flood Awareness Map, namely High, Medium, Low and very low.
The river flood High likelihood layer consists of the 5% Annual Exceedance Probability (AEP) (20 year Average Recurrence Interval (ARI)) flood extent. The extent was sourced from Brisbane River Catchment Flood Study (BMT, 2017) which was commissioned by State Government.
The river flood Medium likelihood layer consists of the 1% AEP (100 year ARI) flood extent (outside high likelihood area). The extent was sourced from Brisbane River Catchment Flood Study (BMT, 2017) which was commissioned by State Government.
The river flood Low likelihood layer consists of the 0.2% AEP (500 year ARI) flood extent (outside high and medium likelihood areas). The extent was sourced from Brisbane River Catchment Flood Study (BMT, 2017) which was commissioned by State Government.
The river flood Very Low likelihood layer consists of the Extent of the 0.05% AEP (2000 year ARI) flood extent (outside high, medium and low likelihood areas). The extent was sourced from Brisbane River Catchment Flood Study (BMT, 2017) which was commissioned by State Government.