Australia — Living in a bushfire-prone environment is complex and requires more than a lifetime of experience. For most of us, experiencing a bushfire at our back door might only be a once-in-a-lifetime event. Therefore we rely on the knowledge of others to guide us.
Condensing it all into three words “Leave and Live” is clearly too simplistic. Yet such a slogan is needed to make a point your life may be threatened by a bushfire so avoid it by not being in such an area on a day when large bushfires are likely.
As Joan Webster has repeatedly pointed out, (The Age, Comment, 30/12), the decision to leave your home is not trivial. The complexity of bushfires means those with access to information, such as government agencies, play an important role in making it readily available to those living in bushfire-prone areas. This was a major thrust of the 2009 Victorian Bushfires Royal Commission’s recommendations.
And we do need to learn from the past, as Professor Tom Griffiths argues (The Age, Letters, 31/12). A major factor contributing to the loss of life and property in the past decade is the landscape context. This context has not been adequately accounted for in much of the research and therefore guides, such as the Australian Standard for “Construction of Buildings in Bushfire Prone Areas”, which only really consider the environment within 100 metres of a house. This shortcoming is acknowledged in Victoria’s planning regulations, which require that the broader landscape be taken into consideration. But how?
First, we need a detailed map of the state showing areas that might be directly exposed to a bushfire under different severities of weather, for example Severe, Extreme and “Code Red” conditions. The extent of a bushfire is greater when the weather is more severe. Such maps would show where people might be exposed to a bushfire on a particular day and importantly, areas not likely to be exposed that would therefore be a safe place to seek refuge. This would help answer the question: “Leave and go where?” Even regional towns and parts of Melbourne could be exposed.
Second, not all parts of the state are likely to be subjected to the same-severity fire. Mountainous and forested areas are much more likely to carry large fires that could induce cyclone-strength winds. In southern Australia we do not build structures to be cyclone-proof so such winds could break windows or tear off roofs, making them unsuitable shelter. The Australian Standard for bushfire areas does not consider damage by strong winds. Maps showing areas where strong convective induced winds could occur would help individuals and communities make fire plans.
Third, in large, well-developed fires in eucalypt forest, there is no simple flaming front moving across the landscape at a regular speed. Eucalypt fires have a pronounced spotting process, so an area up to 10 kilometres downwind can be ignited in a few minutes. People can find themselves surrounded by fire, making evacuation virtually impossible. These spotfires can join and produce a firestorm such as was experienced at Strathewen and Marysville on Black Saturday. However, such conditions will only exist within areas about five kilometres from a forested ridge or range. The conditions that lead to catastrophic fires are never uniform across the state.
The CFA promotes the development and use of a bushfire plan. This should include a range of options depending on the threat and personal circumstance, with only one option being to leave early. Mass evacuations are impractical, so we have to rely on good planning, good preparation and appropriate response. “Leave and Live” is not always going to be the safest and most appropriate option. Government agencies must provide more specific information so the community can share the responsibility of fire safety. This is what we have learnt from the past.