National Flood Risk Information Program, Australia

Science Center Objects

On July 1, 2012, Australia commenced the National Flood Risk Information Program (NFRIP), which includes mapping of flood extents from the entire historical archive of Landsat data over Australia (National Flood Information Portal, 2013). The Australian Government’s Natural Disaster Insurance Review highlighted the lack of consistency across the country in the way flood-risk information was collected and made available to users. It also recognized the need for consumers to be aware of the natural disaster risks they may face, as well as the benefits of making flood-risk information more readily accessible.

Authors: Larisa Serbina and Holly Miller

The aim of the NFRIP is to improve the quality, availability and accessibility of flood-risk information across Australia, and raise community awareness of flood risks (Medhavy Thankappan, Geoscience Australia, written commun., 2013). Additionally, Australia’s Department of Human Services is considering using satellite imagery to determine whether a financial assistance claim for hardship due to flooding is valid. This would be done by comparing the location of a claimant’s home against a flood extent mapped with satellite imagery. The outcome of this data use would minimize the probability of unjustified claims and expedite the payment process to those who are experiencing hardship.

Landsat is a very valuable tool in these endeavors; however, several challenges exist in using the data. For example, the accuracy of surface-water extent is determined by the spatial and spectral characteristics of the satellite data from which it is derived. Since the spatial resolution of Landsat is 30 m, water bodies smaller than the spatial resolution may be difficult to identify. The quality of the image could also be affected by clouds or cloud shadows. The accuracy of final flood-extent maps is therefore influenced by these factors (Thankappan, 2007). In addition to the aforementioned issues, during the 2011–12 flooding of Queensland, data from Landsat 5 was not available, and Landsat 7 data was affected by the scan-line corrector issue. This forced Geoscience Australia to use Disaster Monitoring Constellation International Imaging (DMCii) and other commercial satellites to track the progress of flooding along several major rivers in New South Wales over a period of three months. The cost of commercial data acquisition for the 2012 floods was close to $100,000. The commercial data, especially DMCii, provided broader and more frequent coverage than Landsat, at the expense of spectral information. This lack of spectral information made the data harder to analyze (Norman Mueller, Geoscience Australia, written commun., 2013).

References: 

Norman Mueller, Earth Observation Science, National Earth Observation Group Environmental Geoscience Division, GEOSCIENCE AUSTRALIA, Australia.

National Flood Risk Information Portal, 2013, National flood risk information portal: Geoscience Australia, accessed on May 16, 2013 at http://www.ga.gov.au/hazards/flood/flood-capabilities/national-flood-risk-information-project.html.

Medhavy Thankappan, Section Leader, Earth Observation Science, National Earth Observation Group Environmental Geoscience Division, GEOSCIENCE AUSTRALIA, Australia.

Thankappan, Medhavy, 2007, Gippsland flooding revealed: AusGeo News, no. 87, accessed on May 16, 2013 at http://www.ga.gov.au/ausgeonews/ausgeonews200709/gippsland.jsp.