Fuel Reduction Burning in WA’s South-west Forests September 2012
The submission is addressed to DEC, to the Office of Bushfire Risk Management (OBRM), the Conservation Commission (CCWA) and the State Emergency Management Committee (SEMC) … all of whom have a responsibility to ensure effective bushfire management in WA.
This paper is one of a series produced by the Bushfire Front over the years expressing our concern about the standard of bushfire management in Western Australia. It has been prepared to stimulate a review of the performance of the Department of Environment and Conservation (DEC), specifically the department’s fuel reduction burning program in the south-west forests.
The paper is prepared by members of the Bushfire Front, who have a collective fire experience exceeding 400 years, reaching back to the 1950s and covering bushfire science, fuel reduction burning, strategic planning and fire suppression.
2. The task
DEC is responsible for approximately 2.5 million hectares of forest in State forests, national parks, nature reserves and other ‘conservation’ land tenures in the south-west of the State. These areas constitute a bushfire hazard and a potential threat to people, assets and environmental values, because:
* Each year the south-west region experiences a summer period (“the fire season”) in which there are drought conditions, occasional heatwaves, strong, dry winds and lightning storms, i.e., climatic conditions conducive to bushfire occurrence.
* There is a history of bushfires occurring in this region going back to the first days of European settlement, and there is every expectation that they will occur in the future, lit by accident, arson or lightning.
* WA’s native forests accumulate bushfire fuels in the absence of fire, on the ground in the form of ‘litter’, in the shrub layer and as bark on the trees. This fuel becomes highly flammable when dry, and it becomes dry every summer.
* The more fuel, the more intense will be a fire, the more damage the fire will do and the more difficult, dangerous and costly it becomes to control.
* Human assets and values and community infrastructure that are threatened by fire are distributed throughout the forest region and around its perimeter, especially in residential areas at the margins between cities and country, and in prime holiday real estate in places like Margaret River.
DEC, as an arm of government, and as ‘owner/occupier’ (as defined under the Bushfires Act), has a responsibility to minimise the fire hazard on the lands it manages, and to reduce the threat that bushfires starting on this land will cause loss of life or damage to personal, environmental or community assets.
3. The basic principle of land management and conservation
There is a basic principle that applies universally to conservation and land management in bushfire-prone regions: “If effective bushfire management is not first achieved, no other land management or conservation objective can be achieved”.
The Bushfire Front is not convinced that DEC acknowledges this principle. Their strategic plan indicates that their primary objectives are conservation of biodiversity and provision of visitor services. Fire management is not identified as a core function, let alone a critical priority.
4. Potted history of fire management in south-west forests
The first forest managers appointed after the creation of State forests in WA (in the 1920s) were trained in Europe, where the forests are vastly different. They were imbued with the idea that fire must be permanently excluded from the forest. They attempted to build a fire management system based on early detection and rapid suppression of all fires. Fuel reduction burning was done only in narrow firebreak strips around protected forests. This system failed abysmally when fuels in the long unburnt forest became so heavy that fires occurring in them (often as a result of hopovers from the firebreak strip burning) could no longer be suppressed, and easily spotted over the small fuel reduced areas. The culmination of this “First Approach” were the great bushfires of the 1950s and early 1960s. The losses sustained in these fires led to a revision of the fire exclusion policy and the adoption of fuel reduction burning across the forest.
After the bushfires in 1961 (in which four towns were burnt down and hundreds of thousands of hectares of forest incinerated) the Forests Department steadily perfected a new system, i.e., a “Second Approach”. This involved broad-acre prescribed fuel reduction burning under mild weather conditions, based on research into fire behaviour, a strategic ‘Master Plan’, and using aircraft ignition. In addition, the department maintained a network of thirteen districts across the region, each with a cadre of experienced firefighters and fire officers. They were supported by an extensive resource of personnel and machinery in the timber industry. This approach was highly successful. Large, high intensity bushfires were eliminated from the south-west for a period of nearly thirty years. The system held up even during extreme weather events, such as the Cyclone Alby bushfire crisis of 1978.
During the mid-1990s this approach began to be eroded by the new forest manager, the Department of Conservation and Land Management, now DEC. Forest districts were closed, recruitment of forest officers ceased, the fuel reduction burning program was reduced by more than half, many experienced staff left the department and were not replaced. The department’s priority shifted from land management (incorporating fire protection) to biodiversity conservation.
During this period DEC’s task was made more difficult by the actions of environmentalists who opposed fuel reduction burning in the belief that it destroyed biodiversity (a claim unsupported by any scientific evidence) and who convinced successive governments that keeping Perth city free of smoke from fuel reduction burning was more important than protecting forests and rural communities from bushfire damage.
At the same time, another government decision led to the decimation of the timber industry, removing a key south-west fire suppression resource. In its place, DEC has increasingly relied on aerial water bombing as the front-line fire attack. As has been repeatedly proven in eastern Australia, the USA and elsewhere, it is impossible to control a fire burning in heavy fuels under severe weather conditions irrespective of the number or size of aircraft or other resources. Increasingly during the late 1990s and earl 2000s, DEC moved the clock back: doing less fuel reduction and placing greater reliance on suppression. This represented a return to the ‘First Approach’ of the 1920s, an approach that failed so dramatically.
DEC’s approach has also failed. The number of damaging fires has escalated in recent years, paralleling the deterioration in Departmental preparedness and performance. This was brought home to city people when a massive fire in the Perth hills in 2007 severely damaged the catchment of the Mundaring Weir, killed millions of mature trees and blanketed the city with smoke for days. There has also been a heavy public and media focus on the Margaret River fire of 2011. This resulted from an escaped DEC burn and was followed by an inquiry by Mick Keelty. The Keelty report highlighted DEC’s loss of fire experience and capacity, and their failure to adopt a basic risk management philosophy.
5. Comparing the fuel reduction burning ‘targets’
During the application of the Second Approach, the Forests Department had a burning target of 300,000 ha per annum, and achieved this on a regular basis. This equated to an annual coverage of fuel reduction on approximately 12% of the forest under protection.
By contrast, DEC has adopted a target for fuel reduction of 200,000 ha which is equivalent to approximately 8% of the area to be protected.
6. Why is the burning target significant?
When 8% is burned annually, the average turn-around time between burns (known as the ‘burning rotation’) on any area of forest is 12 years. By contrast, a 12% target translates into an average turn-around time of 8 years.
The rationale for selecting the 12% figure and the 8-year rotation was based on two sets of data:
1. The first was a detailed analysis of the 1961 Dwellingup Fire made by forest officer Wally Eastman. He mapped areas where the fire had burnt as a crown fire1 and found that this correlated with areas where the fuel age was 5-6 years or older. This is significant because it is crown fires that do all the damage.
2. The second emerged from fire behaviour research by George Peet and others in the jarrah forest. This demonstrated that the threshold levels for determining whether a fire would be a ground fire or a crown fire (under most weather conditions) was 8 tonnes of fuel to the hectare. Peet also determined that most jarrah forest accumulates 8 tonnes/hectare of fuel in about 5-7 years.
From this work it was concluded that if fuel ages were kept below about 6-8 years for the bulk of the jarrah forest, the likelihood of the occurrence of unstoppable crown fires would be greatly reduced. [Note: the fuel accumulation and the burning rotation targets are slightly different for wandoo and karri forest, refinements of the system not discussed here].
The work of Eastman and Peet was followed by many years of practical observation by firefighters in south-west forests. This experience showed repeatedly that a crown fire burning into an area where the fuels had been reduced and were only 0-3 years old would drop to the ground and here firefighters had a chance to suppress it. The beauty of a burning rotation of 6 years in the jarrah forest is that 50% of the forest is in this condition.
7. The significance of area and distribution of burning
The area burnt each year by itself is not a good indicator of the effectiveness of a fuel reduction burning program. Three other things are essential:
* Burns must be big enough (or deep enough) to stop the run of a crown fire which is throwing spotfires ahead of itself. A small area of low fuel surrounded by heavy fuel, or a narrow strip of low fuel adjacent to an asset, offers very little protection to a large fire driving in from the hinterland. Crown fires will go straight over the top, via their ember storm, or will burn around the edges.2
* Burns must be strategically placed (in WA forests) with the long axis being north-east to south-west. This is to maximise protection against the run of fires on the worst days, i.e., when there are gale force nor’west winds during a heatwave.
* Burns must be widely distributed across the landscape so there is a mosaic of fuel ages. This makes burning easier, safer and less costly, and provides optimum protection from large fires, because of the likelihood that any fire burning in one fuel age must soon run into an area with a younger fuel age.
8. The DEC achievement
DEC’s fire management approach is deficient in many aspects. There are now only six administrative centres (districts in the main forest belt) where there were previously thirteen; the fire research program has been curtailed; they have failed to put in place a succession plan to ensure ongoing availability of trained staff and employees or of district leaders; and there is a growing reliance on water bombers which are only effective under relatively mild conditions.
However, the main problems germane to this submission are:
1. In adopting a burning target of 8%, DEC ensures that the average turn-around time between burns will be >12 years, meaning that at any one time more than half the forest will be carrying fuels capable of generating a crown fire.
2. In fact, in recent years, DEC has generally only achieved an annual burn of about 120,000 ha. This is equivalent to only about 5% of the protectable area. If this rate of burning continues it will mean that the rotation length between burns will be about 21 years and the area carrying fuels capable of generating an unstoppable crown fires will be approximately 66% of the forest to be protected. In effect, this is the situation that prevailed in south-west forests in the early 1950s and which lead to the bushfires that destroyed four southwest towns.
3. DEC has been pressured to focus its burning effort on small burns close to assets. This gives an illusion of an effective fuel reduction program. On the contrary, small burns or narrow strips of fuel-reduced country are useless in stopping the path of a major fire that has developed in adjoining heavy fuels on a hot windy day in mid-summer. Such a fire will not be stoppable before it drives into residential and other fire-vulnerable areas.
4. The situation in the jarrah forest is serious but in the karri forest it is critical. Large areas of the karri forest, including prime old growth forest in national parks and valuable regrowth forests are now carrying fuels up to 35 years old. Fires in these areas on a bad day in summer will do immense damage.
It is pointed out that again and again the BFF has written to Ministers or talked to senior staff in DEC and raised these issues, but never once has the dimension of the problem, or the urgency of the need to fix it, been accepted.
9. We are not critical of DEC fire management staff
Fire operations staff in DEC do a magnificent job given the constraints under which they operate, and the fact that they are increasingly isolated as a ‘minority group’ within the department. The days are gone when practically everyone in the organisation supported the prescribed burning program and were involved in its implementation. Unfortunately DEC’s fire staff today are:
* Few in number, overworked, overwhelmed by bureaucratic paperwork, under stress, getting older and unsupported in the community;
* Operating in an organisation where it is not explicitly acknowledged that biodiversity conservation can only be achieved if effective bushfire management is first ensured;
* In the presence of departmental colleagues who are openly critical of fuel reduction burning and those who engage in it;
* Saddled with a burning target that only makes their job harder; and
* Led by people who mostly have no experience in bushfire management.
10. What needs to be done?
The first step to resolving any problem is to acknowledge there is a problem. If DEC cannot see it for themselves, they must commission a comprehensive independent analysis of its fire management program, similar to the study done by Chris Muller 10 years ago.
We would like to see a written Fire Management Recovery Plan emerge from such a review, endorsed by the Minister and DEC’s Corporate Executive and given funding priority. Our hope is that a ‘Fourth Approach’ would emerge, based on experience, wisdom and scientific research of the last 90 years. Such a plan would incorporate (amongst other things):
* A revised annual target, based on the need to minimise crown fire occurrence in south-west forests;
* Identification of the constraints to the annual burning program, and strategies to eliminate them;
* Burn rotations specified for the different forest types, taking into account wildfire threat analysis but primarily based on the need to minimise crown fires; and
* A strategy for overcoming the backlog in burning that has built up over the last decade; and
Finally, DEC must examine its underpinning principles and objectives: where do they rank the priority of minimising bushfire damage in the south west? How does bushfire management stand in relation to funding for the ‘mainstream’ DEC programs? Are they committed to system upgrade, or do they accept ‘more of the same’ in the years ahead? This philosophical review is just as critical as dealing with the operational issues raised in this paper.
11. Responsibility for action
DEC could rise up and take responsibility themselves for fixing the problem. This is what the Forests Department did in 1954 when the First Approach failed, and they revised it and devised the Second Approach.
If DEC is unwilling or unable to take on this responsibility, the responsibility becomes that of government, operating through the Minister, the State Emergency Management Committee (SEMC) and the Office of Bushfire Risk Management (OBRM).
Indeed, the Bushfire Front sees the challenge of getting DEC’s bushfire management back on the rails is the first and greatest test of both the newly restructured SEMC and OBRM.
12. The parallel problem on private land
Unacceptable fuel levels on DEC land are paralleled by an even worse situation on much of the private land and on Shire and roadside reserves throughout the south-west. This problem has at last been recognised by FESA and some Local Government Authorities. What is not clear is how the problem can be tackled, given the myriad of land owners involved, the lack of collaborative arrangements and the level of land owner fire competence. The task is way beyond that of the small number of volunteer bushfire brigades who are only available for fuel reduction work on a part-time basis.
While the situation on private and Shire land makes DEC’s task only harder (because every burn they do against long-unburnt bush is tricky, risky and costly) it also emphasises the importance of DEC setting the highest possible standards of leadership and professionalism in minimising the bushfire threat to residential areas and biodiversity. If DEC does not do its fire job properly, there will be less incentive for others to do so.
1 A ‘crown fire’ is one in which the entire forest profile from the ground to the tops of the trees burns at once. Crown fires are unstoppable by humans because of their high intensity, and they move very rapidly because the generate a stream of burning embers carried downwind of the head of the fire. A ‘ground fire’ on the other hand burns only through the litter layer on the surface of the forest, and can usually be suppressed by firefighters under most conditions.
2 This is why the Bushfire Front argues against the recommendations of environmentalists, that the burning program should be confined to narrow strips around residential areas. This is a waste of time if the hinterland is left unburned for long periods.