Australian Flood Maps

Australian Flood Maps

Our Australia Flood Map was first created in 2014 as part of JBA’s Global Flood Map (GFM®) and provides undefended flood hazard maps for six return periods (20, 50, 100, 200, 500 and 1,500-year). The flood map has since been subject to updates in 2015 and 2016. The latest update focuses on the following:

  • Improved mapping in areas where high quality LiDAR data are now available (all data remains at 30m resolution).

  • Improved classification of river and surface water flood type based on a more accurate river location dataset.

  • Map coverage increased to include small islands.

  • Defended Area polygons have been revised to correspond with the flood map improvements

Additional LIDAR input

A digital terrain model (DTM) provides a digital representation of the true ground level of the earth.

A digital surface model (DSM) represents the earth’s surface as detected by radar and therefore includes features such as tree canopies and tall buildings.

For the 2015 Australia Flood Map, Intermap’s NEXTMap WORLD30 DSM and a variety of bareearth DTM datasets were used. For the 2016 maps, the elevation data has been upgraded in key areas using Geoscience Australia’s LiDAR data at 30m resolution.

Use in Australia

The use of broad-scale flood modelling may support a range of purposes in Australia, including strategic management for the transport and utilities sector, governments, and re/insurance.  This could include:

  • Use in large-scale strategic upgrades of transport or utilities networks.  

  • Identifying where flooding occurs

  • Providing quantitative data for analysis

  • Providing information on the road closure, for instance a statistical

  • Analysis of the expected number of days impacted at waterway crossings, e.g. time/delay/inundation per year. 

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