Flood Awareness Map
The Flood Awareness Map (click on the map to the left to access) is an interactive tool that shows the areas of South Australia that could be flooded in specific scenarios.
The Flood Awareness Map is made up of smaller maps commissioned mainly by local councils and State Government over several years, using different technologies and for a variety of purposes. Some are more accurate and detailed than others. Ensure you check whether the accuracy and detail available suits your needs.
When you open the Flood Awareness Map, please read the Terms and Conditions carefully.
To find out about the author, published date, commissioning authority and details about the flood scenario in your map of interest, click the information button next to the flood map in the list of flood studies. For detailed information, ask the author for a copy of the flood study.
Important:
The absence of maps in an area of South Australia does not mean there is no flood risk. It may be that no maps are available at the location, or that the location is not affected by the scenario displayed.
The Flood Awareness Map does not show real-time or predictive information about a flood.
1.
Purposes of flood maps
Flood maps have been produced for a variety of reasons including to:
- identify which areas are at high risk of flooding to plan emergency response
- determine areas suitable for development, and assess the adequacy of existing drainage infrastructure
- assist in the design of flood mitigation strategies such as detention dams, levees and pipes
- explore a specific scenario that may result in a flood such as a dam break
- provide a guide for long-term planning against increased flooding as a result of sea level rise
- look at the impact of future development within a catchment or floodplain on the flood risk
- examine the impact of a potential stormwater harvesting project on flood risk.
2.
Type of flooding considered
Most of the studies cover riverine and stormwater flooding. Some investigate flood risk from rainfall events, others examine flood mitigation options, and some are coastal flood studies. Some flood maps consider impacts of climate change, others do not.
For more information on coastal inundation consider visiting the
Coastal Flood Mapping Viewer.
3.
How flood maps are made
Flood maps used to be created by hand by plotting a predicted flood level onto a contour map of ground levels. Now, it is done using a range of complex computer programs which model how a volume of water will travel across a landscape. Information typically produced from the models include location and depth of potential inundation, velocity, number of properties inundated and hazards to people (a factor of water velocity and depth).
Before even beginning to model a flood, lots of data must be obtained about the catchment and types of events that will cause flooding.
Using this knowledge, flood modellers select inputs for the specific flood and area they wish to model. Data is selected for entry into the flood model based on best available information at that time.
The types of data often used to develop a flood map include:
- rainfall and river data from historical records or synthetic rainfall events developed by the Bureau of Meteorology
- roads, roofs and other impermeable surfaces, which can lead to a greater volume of runoff
- soil moisture and capacity of the soil type to absorb runoff
- ground levels of rivers, creeks and floodplains
- location and size of built objects such as bridges, pipes, levee banks and dams
- “roughness" of the rivers, creeks and floodplains: for example, a creek or floodplain covered with dense vegetation or smooth concrete influences how quickly water can move across it and therefore the depth and velocity of floodwaters
- downstream water levels (sea levels may include an allowance for climate change)
- historical flood levels and extent of flooding.
To make a map as realistic as possible, modellers often calibrate their model against historical floods. Comparing real information against the modelled information for the same event can improve the reliability of the model. But this is difficult or impossible in areas where floods have not been recorded in a long time, the flood scenario is for a flood larger than has been recorded, or historical data is inadequate.
Ultimately, while flood maps aim to represent a likely flood event, a flood that happens in reality may be different to that shown on a map.
Catchment environments will change over time. Newer flood maps may better represent current conditions and will include recent development such as housing, roads and water management infrastructure which can alter the characteristics of a flood. Some flood maps show future scenarios.
Other flood mapping portals
This Geoscience Australia portal makes flood information from around Australia accessible in one place. However, some of the individual flood maps on the Flood Awareness Map have not been shared with the Australian Flood Risk Information Portal. Owners of the individual maps decide whether to share them or not.
This interactive Flood Mapping Tool identifies areas on Eyre Peninsula and the Limestone Coast that may be vulnerable to coastal flooding due to storm surge and/or sea level rise.
Local Council websites
Various local Councils display flood mapping on their own website. Go to your Council's website to find out.
Funding for the Flood Awareness Map and associated web pages was provided by the Commonwealth Government and the South Australian State Government from the Natural Disaster Resilience Program administered by the South Australia Fire and Emergency Service Commission.
Resources & tools