The threat of fire in Victoria

Sunday (9 February 2014) will be the worst fire conditions that Victoria has experienced since 2009. It’s a very serious position that we are in and it is all due to the fact that we’ve had extended heat periods. The heat will extend all through Saturday night into Sunday and Sunday actually deteriorates with extreme fire danger rating in six districts.

Those six districts are right through Central Victoria, North Eastern and Gippsland but all Victorians should understand that tomorrow anywhere in Victoria, fires will run, and run hard.

Fire intensity: they will be furious, they will be fast, they will be out of control and people need to be very aware of that.

Don’t start a fire. We need people to understand that we do not need fires anywhere in Victoria and we certainly don’t need people that in foolish steps are the cause of the fire.

We also remind everyone to have a plan. It is time to refresh your plan. Make sure that the plan suits your needs. Where ever you are in Victoria, if you are home, if you are travelling, make sure that you’ve got a plan. If you intend to leave, leave early. If you intend to leave know where you are going. Take what you need to take with you. But certainly consider the fact of leaving early. Extreme fire danger rating means fires will be intense and very fast moving.

Today we have already experienced that. We’ve got fires in Gippsland. There is one in Latrobe Valley, near, between Moe and Morwell. Started last night. The Princes Highway was closed, reopened and is now closed again. Due to the fact that the fire is now active again. That tells us that getting control of these fires is very difficult and will be challenging in any part of Victoria.1

This warning from Mr Craig Lapsley, Fire Services Commissioner, on 8 February 2014 and repeated throughout the weekend, could not have been clearer. Victorians were to prepare for potentially catastrophic fire conditions on 9 February 2014.

Mr Lapsley delivered this warning in the context of Victoria’s vulnerability to fire, past experience with bushfires, and the predicted weather forecast.

VICTORIA’S VULNERABILITY TO FIRE

Since the 1950s, Australia has experienced an increase in the duration, frequency and intensity of heatwaves. Since the 1970s, there has been a noticeable increase in extreme fire weather and lengthened fire seasons across Australia, particularly in the south-east of the country. The risk of bushfire will continue to increase, with more and more extremely hot days and intense heatwaves predicted.2

Every fire season, Victoria experiences bushfires. Many of these bushfires are catastrophic fire events resulting in the loss of life and property. Between February 1851 and February 2007, there were 52 major fire events in Victoria resulting in 372 deaths, extensive property, flora and fauna loss, and the burning of millions of hectares of land (Teague, McLeod & Pascoe, 2010). On 7 February 2009, the bushfires of Black Saturday resulted in the death of 173 Victorians. Many of these fires (including the Black Saturday fires) have impacted the Gippsland area.

Extreme fire danger weather in Victoria routinely occurs in February. Extreme fire danger weather is characterised by a strong to gale force north-westerly wind, frequently followed by a strong south-westerly wind change. The most turbulent fire behaviour almost invariably occurs before and after the wind change. A fire igniting under the influence of a north-westerly wind rapidly extends a narrow wind-driven front to the south-east before the wind change causes the eastern flank of the fire to whip around to the north-east, creating a wider fire front.3 This weather pattern and its effect on fire behaviour is illustrated in Figure 2.1.

Figure 2.1 Effects of weather on the fire front
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Image Source 2009 Victorian Bushfires Royal Comission Final Report

Embers from the fire front follow the course of the strong, blustery winds associated with the wind change, and are further exacerbated by dry fuel sources. Ember throw or spotting is characteristic of fast running and destructive fires.4 Additional fire, or fire spread, caused by ember spotting is ‘a well-demonstrated and well-known propensity of fires and has been for many years.’5

Tree bark is responsible for most spotting or ember throw ahead of a bushfire. Many of Australia’s Eucalypt species shed their bark annually, resulting in the accumulation of bark ribbons, providing an ignition source in a high intensity fire. These bark ribbons can stay alight in excess of 30 minutes. They can travel up to five kilometres in strong winds, and 20–30 kilometres if caught up in convection columns.6

Victoria is undeniably one of the most bushfire prone areas in the world. Despite the high risk of a catastrophic fire event occurring, many Victorians continue to underestimate the probability of fire events and ‘hope for the best’ in the fire season. This approach ultimately impedes their ability to prepare for, and to respond to, the reality of fire.

REDUCING COMPLACENCY

Warnings such as those issued by Mr Lapsley on 8 February 2014 are made in an attempt to reduce complacency about the risk of bushfires.

The risk of bushfire is not isolated to regional forested areas of Victoria. Areas of suburban Melbourne are susceptible, although less so than country towns. Grass fires pose a significant threat, especially to farming regions. Experience has demonstrated that the most vulnerable fire areas are near forests, elevated land and open cut mines.

The particular vulnerability of open cut coal mines to fire is evident not just in Australia but all over the world. Brown coal mined in Victoria has a number of features which differentiate it from black coal. Both black and brown coal are highly combustible. However, brown coal is more porous. This can make fire in a brown coal mine more difficult to extinguish. Fire in brown coal can easily get within the coal and smoulder beneath the surface because of jointing (partings due to geological forces). This phenomenon is not replicated in black coal. Additionally, Victorian brown coal is unique in the sense that there is only a thin layer of overburden sitting above very deep coal seams. It is for these reasons that Victorian open cut coal mines are so vulnerable to fire.7

2013/2014 SUMMER FIRE CONDITIONS

As is typical of Victorian summers, 2014 was marked by hot and dry weather conditions. By the middle of January much of the grassland and forest areas across Victoria had dried out, presenting a significant fire hazard. Under northerly winds, these conditions created the potential for high rates of fire spread.8

An extreme heatwave affected Victoria from 13–17 January 2014, breaking numerous records for extended periods of heat, including the hottest four-day period on record for both maximum and daily mean temperature.9 This behaviour is illustrated in Figure 2.2.

Figure 2.2 Overview of the 2013–2014 fire conditions10

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By the middle of January 2014, several major fires were burning across Victoria. These included a 55,100 hectare fire in the northern Grampians region, and the Goongerah–Deddick Trail fire in East Gippsland, which ignited on 16 January 2014 and ultimately burned for 71 days across 165,806 hectares.11 An overview of the fires in Victoria in January to March 2014 is contained in Figure 2.3.

Figure 2.3 Overview of fires in Victoria January – March 201412

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WORST FIRE CONDITIONS EXPECTED SINCE BLACK SATURDAY 2009

The weather conditions forecast for the weekend of 8 and 9 February 2014 were the most dangerous fire conditions since the Black Saturday fires in 2009. The Latrobe Valley Airport weather station had recorded 16 days above 30 degrees and only 28.2 millimetres of total rainfall for 2014 prior to 9 February.13

Prior to and during the weekend of 8 and 9 February 2014, the Fire Services Commissioner and the Chief Health Officer made several announcements warning the community about the potential for extreme weather conditions and associated fire and health risks.14

By the evening of 7 February 2014, 16 fires were listed as ‘going’ across Victoria. By 4 pm on 8 February 2014, there were 25 fires listed as ‘going’ across the State, and 9 February 2014 was forecast to be a critical fire weather day following hot overnight conditions. The State was managing these fire events from the State Control Centre and all firefighting resources not already committed to existing fires were at maximum levels of readiness.15