- Title:
-
Effects of Fire Retardants on Vegetation in Eastern Australian Heathlands: A preliminary investigation
- Date:
- November 2003
- Organisations
- DSE
- Authors:
- T.L. Bell
- Location:
- Australia, VIC, Australia
Overview
Fire retardants have been used around the World in forest fire suppression operations for more than thirty-five years, particularly in places such as North America and the southern Mediterranean. In Victoria and other Australian States fire retardants have been used for approximately thirty years.Retardant is typically used to help control wildfires when access by ground crews is difficult or unsafe, or when there will be lengthy travel times for crews to arrive at the fire. Retardants restrict the spread of fire and enable firefighters to control the extent of the area burnt. In an average year, Victoria experiences more than 600 wildfires in its parks and forests. These wildfires burn about 110,000 hectares. Retardant is used to assist with suppression on about ten percent of these fires.
Many different fire retardants are available commercially, but not all have been subject to rigorous environmental and health studies. Victoria, in common with other land management agencies in Australia, has adopted a position of only using those fire retardants that have been subjected to lengthy testing and approval by the United States Department of Agriculture (USDA).
In 1998, the Department sought advice from Victoria’s State Chemistry Laboratory following local community concerns about water quality following the extensive (32 000 ha) Caledonia wildfire in Gippsland in January 1998. The State Chemistry Laboratory advised that the claims of risk to public health were not scientifically well-founded. Subsequent investigations of water quality in the Macalister River by the local water authority found no evidence of contamination by fire retardants. There were, however, significantly increased levels of suspended sediments thought to be due to the extensive surface flows resulting from heavy thunderstorm activity after the fire.
To assist Victorian park and forest managers to better evaluate the wildfire control options available, the Department in 1999 commissioned the CSIRO Division of Forestry and Forest Products to assess the effectiveness and environmental risk associated with the use of retardants. The resultant report - Assessment of the effectiveness and environment risk of the use of retardants to assist in wildfire control in Victoria (DSE Fire Research Report No. 50, February 2000) - represented the most detailed examination of the subject in an Australian context.
The CSIRO report stated “We consider that the aerial application of long-term fire retardant which meets or exceeds the USDA Forest Service performance standard is essential for efficient fire fighting in the Victorian environment…”
The CSIRO review did, however, recommend that further research into the impact of the use of retardant on specific Australian ecosystems be conducted.
In response to the CSIRO findings, the Department further strengthened its management of the use of fire retardants. In addition, it set up a specific research program to examine the impact of long-term fire retardant on three elements of eastern Australian heathland communities, namely the vegetation, invertebrates and soils. This report derives from one of those studies.
More generally, Victoria’s Code of Practice for Fire Management on Public Land sets out principles for environmental care that underpin all fire management activities. The application of chemicals in wildfire suppression does have some environmental impacts, as does the building of control lines (with either bulldozers or hand-tools) and backburning—but so too does uncontrolled wildfire. Managers of park and forest fires have to make regular judgements about these matters; often in highly dynamic situations. The information derived from these studies should further assist land managers in the judgements they are required to make when managing wildfire suppression operations.
