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SELECT COMMITTEE ON AGRICULTURAL AND RELATED INDUSTRIES
14/05/2010
Bushfires in Australia

CHAIR —Welcome. I invite you to make an opening statement. If you would like to make any alterations to anything you have already presented, now is the opportunity.

Dr Driscoll —Thank you. I have an opening statement. I have been asked to contribute here based on a peer reviewed research paper on which I was the lead author—and I have some copies here for the committee. It is called ‘Resolving conflicts in fire management using decision theory: asset-protection versus biodiversity conservation’. The paper is co-authored by a range of leading Australian fire ecologists and land managers. Some of the best Australian scientific minds contributed to this paper, and that includes a range of practical managers and state government agency staff. So this paper has quite a broad collaborative base.

What we are calling for here is an evidence based approach to fire management. We have set out a process by which this can be achieved. There are three fundamental steps that I will talk about in this approach. The first one is to define the objectives. There are a range of objectives that our society has for managing fire and that includes protecting houses, managing the landscape in an ecologically sustainable way, protecting human health and reducing carbon emissions. Human health and carbon emissions are not my area of expertise, so I will focus mainly on the topic of our paper: protecting assets and ecological sustainability.

Once you have defined your objectives, the next step is to put on the table all of the different ways for achieving those objectives. Do not just focus on one possible way of managing the fire problem; consider fuel management, engineering solutions and social solutions. Fuel management might include widespread fuel reduction burning, strategic fuel reduction burning or perhaps mechanical fuel removal in some situations. Engineering solutions could include sprinkler systems, fire resistant housing or even bunkers. Social solutions could include ignition management is an important one. If you can control ignition management, you can have a big influence on the incidence of unplanned fire. I think improving communications is something that is coming out of the Victorian commission, and I know it came out of the South Australian commission into the Eyre Peninsula fires. And of course the ‘go or stay’ policy is another solution. To make the best choice you need to have all the choices that are available on the table to start with.

The third part is to gather evidence to appraise how effectively each of those options achieves the range of objectives. So we need to work through a range of scenarios using all of the tools that we have available to us to be able to home in on a combination of options that best achieves those multiple objectives. For example, if we took the budget that is available for dealing with the fire management problem and applied it to improving communications and subsidising sprinkler systems and fire resistant housing, would that reduce the number of deaths in the next Black Saturday fire event? Would it make land management more ecologically sustainable? Would it improve people’s health? Would it change our carbon emissions? So what I am concerned about and what my co-authors have been concerned about is that we have not gone through this rational decision making process. We fear that unless we do, poor decisions are going to be made and society’s core objectives will not be achieved even though we could have done much better with the tools we have available to us today.

I want to finish with an example of how new evidence can be used to help appraise the effectiveness of certain fire management options. In particular I want to focus on the question of widespread and frequent fuel reduction burning. I will just quickly mention some examples from the international literature. There is growing evidence that widespread fuel reduction burning is not effective in all situations. There is a paper by Gadellov in 2005 in Ecological Applications talking about the fires in north-western United States who concluded that fuel treatments alone may not be effective in reducing the area burnt under extreme climatic conditions. Another paper in 2009 by Dilitz and colleagues published in the Annals of the Association of American Geography looked at the probability of fire occurring in Lincoln County, Nevada. That concluded that ignition by lightning strike was more important than fuel characteristics for influencing wildfire occurrence. There are two more I will tell you about. Podur and Martell looked at fires in Ontario Canada. In those boreal forests they found that fires burn forests in proportion to their presence and not in proportion to their fuel load. Keeley and Zedler in Ecological Applications talking about southern Californian shrub lands found no evidence to support the idea that fuels limit large fires in Californian scrub communities. The recent drought was a more likely explanation. I mention these just to make the point that there is a growing body of literature which suggests that what we had previously thought about the effectiveness of widespread fuel reduction burning might not be true. The important point is that it is new literature. It means that we need to reappraise what we have been doing in the past and consider new ways of dealing with the problem.

I want to finish with the handout that you have been given. This is an example that Ross Bradstock and Owen Price from Wollongong University prepared for the 2009 Victorian Royal Commission. It is titled, ‘Fire severity patterns in the Victorian fires of February 2007-2009: influence of weather, terrain and land use history.’ It has three graphs on it. On the vertical axes we have ‘probability of CF’, which means probability of crown fire. The probability varies from zero to one up that axis. One means you will certainly get a crown fire; zero means you will never get a crown fire. On the horizontal axes of all of these graphs is the time since fire. So it gives the probability of a crown fire occurring given a certain time since fire, based on the data from the Victorian fires.

Senator BACK —Looking at example (a), there is a probability of one at zero time since the last fire. So the highest probability of a crown fire is at zero time since the last fire.

Dr Driscoll —That is correct. It took me a little while to think that one through, as well.

Senator BACK —In my ignorance I read that to be the more recently the fire, the higher the incidence of crown fire. If it is zero time since the last fire there is nothing in the crown to burn.

Dr Driscoll —You are right. This graph is for an ash forest. When you burn mountain ash forest, it is all killed, and so the crown is the regeneration on the ground. After one year a fire, everything is near the ground, it is uniform and it is easy to burn. So you always get a crown fire but it is a metre or two metres tall.

CHAIR —You get trees that are 100 feet tall.

Dr Driscoll —After a fire the trees are killed. The crown is therefore near the ground. That is what this graph is telling us.

CHAIR —The tree is the statue.

Dr Driscoll —The tree standing there is dead, yes. That is no longer where the crown is, which is why this graph says ‘a 100 per cent chance of crown fire in mountain ash forests one year after fire’.

CHAIR —Is that just quaint language for ground fire?

Dr Driscoll —You can call it whatever you like.

CHAIR —An ordinary old bushy would say that it is a ground fire.

Dr Driscoll —Yes. In fire ecology terminology, the crown is the top of the vegetation.

CHAIR —If there has been a total wipe-out—and we have been to areas where that has occurred—and it is the first year after the fire and it is obviously after spring and some dry fuel or some burnt logs are on the ground, what is the crown going to burn? What is the crown?

Dr Driscoll —In this scenario that Bradstock and Price modelled, it is the top of the live vegetation.

CHAIR —That is just regrowth grass.

Dr Driscoll —No. In a mountain ash forest, what springs up is a whole bunch of new mountain ash trees. A whole lot of seedlings pop up; they are not very tall. That is why this counterintuitive graph appears because the crown is actually quite small, but it is the crown and it does get burnt.

CHAIR —What ignites the green shoots?

Dr Driscoll —Any source of ignition will do it. This is saying that—

CHAIR —Have you ever tried it with a match?

Dr Driscoll —in extreme or moderate weather this environment —this is the part that I have not got to explaining yet——will burn.

Senator BACK —I should not have interrupted you.

CHAIR —Righto. Away you go. I should not have interrupted you either.

Senator BACK —I just needed to understand it.

Dr Driscoll —It is counterintuitive.

Senator BACK —You clarified it in your explanation. Thank you.

Dr Driscoll —The final part of the explanation of these graphs is about the three weather conditions graphed here. Each graph has three lines. You will see that they are described as low, moderate and extreme. These map onto the extreme weather that occurred during the afternoon of Black Saturday, the moderate weather that occurred after the change and the low severity weather that occurred on the subsequent days. I want to make five points about these graphs. The first point is that you can see that the fire weather is the most important thing. It makes the biggest difference to whether there is a crown fire and what the probability of one is. The biggest difference is due to the weather.

The second point is that the fuel age influence is limited to the first few years after the fire. In the report, Bradstock and Price mention that, if you look at the actual data, there is only evidence of an effect time on fire for up to three years. It is implying that these curves have smoothed out that effect over more years than might be expected. So the fuel effect was only evident for up to about three years.

The third point is that the effect of the fuel age on the probability of a crown fire is typically very small. If you look at (b), the damp forest, you will see that, for example, under moderate weather conditions, if the previous fire was one year ago, the probability of a crown fire is in the high fifties. If the previous fire was 100 years ago, it is increased by about 10 per cent. While fuel reduction does influence the probability of a crown fire, it does not influence it very much. Bradstock and Price mentioned that this data is largely driven by unplanned fires. So the ‘time since fire pattern’ is driven by unplanned fires. If these had all been planned fires, the effect size would be smaller because the intensity at which planned fires can burn is lower. After a planned fire, the amount of fuel would be higher and so you would expect this effect size to be smaller.

CHAIR —That is provided it is a monoculture forest and it does not have grassy plains in between the bush forest.

Dr Driscoll —This draws on data from across the forest landscape.

CHAIR —If you go up to the Snow Mountains and come across a grassy plain that has been eaten out, if a crown fire should hit the grassy plain in other than the most extreme weather, the fire stops. Right?

Dr Driscoll —It would depend on the weather.

CHAIR —If there is no fuel load on the grassy plain—I am talking about when we used to eat it out with sheep and cattle or whatever; the other option is to burn it—you stop the fire.

Dr Driscoll —Under mild conditions—

CHAIR —Not just mild but reasonably bad conditions. If it is a crown fire and it is a mile across the plain to the other side and you have not reduced the fuel load on the plain, you spread the fire. If part of the consequence of the low cool burn is that you have got rid of the grassy plain, then you get rid of the fire.

Dr Driscoll —Yes, under some moderate conditions—

CHAIR —This is a very simplified version of life in reality.

Dr Driscoll —This is data from—

CHAIR —Yes, but it does not take into account the scenario—

Dr Driscoll —Black Saturday.

CHAIR —of Black Saturday. I have to say that what happened on Black Saturday was not a normal fire.

Senator BACK —You were going to make a fifth point.

Dr Driscoll —The fifth point—thank you. The fifth point is that these graphs are showing the probability of a crown fire and not the threat to houses. That is a really important point because so much fire research has focused on how the intensity of a fire varies with the amount of fuel load and the probability of a crown fire but it does not very often measure the actual threat that we are worried about, which is whether or not houses are going to be burnt down. That is an area for research. We do not know much about it. Phil Gibbons at ANU is currently doing some research on this and it will probably be available in a couple of months.

To translate that evidence into a decision framework, we would have to ask: how much money do we spend on burning the forest every three years and how effective is that? In damp and dry forest, it is going to reduce the probability of a crown fire by five to 10 per cent. Under extreme conditions—and that is from roughly 70 to 60 per cent in dry forest or 85 to 80 per cent in damp forest—how does that small reduction in the risk of crown fire translate into risk of houses burning down? I do not think we know that yet. And was any marginal gain in saving houses a reasonable trade-off against all of the other competing objectives? Is the marginal gain in asset protection of burning the forest every three years so valuable that it is worth trading off the other objectives? In this scenario, with the burning of the forest every three years, we would certainly see a loss of species throughout the forest and an increase in health related deaths and associated costs, as well as an increase in carbon emissions.

Senator BACK —Thank you. Can I ask you for the first time to confirm whether this data—’ash, damp and dry’—is drawn from the actual circumstance of the Black Saturday fires, or has the data been gathered internationally?

Dr Driscoll —No. The data has been gathered from the Black Saturday fires. This is fire severity mapping from that day.

Senator BACK —Since the Y axis is going out 100 years, do we know that those forests were not burnt for 100 years? How has the data been gathered for 100 years?

Dr Driscoll —There are pretty good records of the age of the ash forests through that area, so it is from either actual records or estimated records based on the nature of the forest.

Senator BACK —I do not know much about the Victorian situation. You did just make the observation about the influence of burning every three years. It is my understanding, and please correct me if I am wrong, that the fuel loads were at the levels they were because there had not been any fuel reduction effort of any sort—either grazing, burning or mechanical removal. Am I wrong in that? You were mentioning the frequency of three-year burnings.

Dr Driscoll —Yes, that is wrong. There are a number of fuel reduction burning patches throughout that area. I have a printout from the DSE website which shows that the nature of the landscape is a mosaic of logged areas, of fuel-reduced burned areas and of unplanned fires throughout the landscape.

Senator BACK —The evidence given to us at our hearing in Victoria was that practically the only area that was saved downwind was due to the fire running into an area that had in fact been burnt about three to four years previously. I know from experience and the experience of firefighters from my own state—of which I was once the Chief Executive Officer of the Bush Fires Board of Western Australia, so I do have some personal knowledge—and I can only quote from the forests with which I am familiar, but we would say about five tonnes to the hectare of fuel on the floor was normally about the upper limit of safety when putting people and equipment in to arrest fires. Their report back to me was that there were 40 to 50 tonnes and, in some instances, 150 tonnes to the hectare. My question is: if the forests in that Victorian region had been burnt frequently how could they have accumulated 40 to 50 or 150 tonnes to the hectare?

Dr Driscoll —No, the forests were not burnt. The whole forest area was not burnt every three years—definitely not. These graphs are based on a range of burn ages—some of which were burnt one or two years previously; some of which were burnt at the time since fire. This is based on time since fire, not frequency, but it gives an indication of what sort of effect you would expect to have on the spread of fire.

Senator BACK —As figure four says, these are model predictions. Can you tell me the extent to which they were tested and therefore in some way validated? I understand the prediction basis but I am concerned about the 100-year timescale. Can you tell me the extent to which field observations have validated or not validated the model predictions?

Dr Driscoll —Yes, there are two things. The first is that the whole time series is based on actual data. There are data points out to 100 years since fire that have guided where those lines are put.

CHAIR —So do you go back after the fire and say, ‘This is a 100-year burn spot and I will have a look about and see what happened’?

Dr Driscoll —That is right. But this was using satellite data—

CHAIR —Can I tell you the flaw in that? On the right day when you get a head fire, generally it does not matter a rat’s what is underneath because you have got the top fire going properly and what is underneath does not matter much.

Dr Driscoll —So is that an argument for or against fuel reduction burning?

CHAIR —No, it is an argument about how you track the difference between the lower fuel loads and the higher fuel loads once you have got a head fire on the right day. How do you determine that it was load that had something to do with the head fire once the eucalypt gets going? I presume you go to fires.

Dr Driscoll —No, I don’t.

CHAIR —There you go. That is why I was curious about the fuel loads and the spread of the fire, and how you can slow a fire down and actually put it out on the right occasions. Perhaps you should go to a fire.

Dr Driscoll —I am not the right person to ask for that.

Senator BACK —The point that I am also trying to get to is that the graphs do not indicate fuel loading. None of the graphs indicate fuel loading. In your five observations, which I have recorded carefully, I cannot see reference to fuel load. If I could just take you through, you mentioned fire weather. I suppose I cannot help but look at this in terms of management.

As you say, fire weather is critically important. There is no doubt about that. I would not have any difficulty in accepting the position of your three graphs, except to say that, from a management perspective, one thing you cannot control is fire weather. So, whilst you point to it being important—and I concur with that—do you agree that there is no control that people preventing or managing fires can have over fire weather?

Dr Driscoll —Obviously, yes.

Senator BACK —You mention that fuel age is limited after the first few years—I think you mentioned three years—and that would not be inconsistent. The third point that I want to take you to is that ‘the effect of fuel age on the crown fire is small’. That certainly would not be my observation and I did not think it was consistent with some of the CSIRO work and other related work that I have seen. I am very familiar with Project Vesta. Are you familiar with it?

Dr Driscoll —I am not very familiar with it but I know of it.

Senator BACK —Sure. It was work that was coordinated by CSIRO but it had involvement in and certainly support from all of Australasia’s fire organisations, as well as Canadians and New Zealanders and others. It was probably the first time that there had actually been burning under controlled conditions. It was in the eucalypt jarrah forests in the south-west of WA. I would ask you to go back and review the statement that the effect of fuel age on crown fire is small. It may have been the case in Victoria, but—

Dr Driscoll —Can I clarify that. The point I am making is in relation to how the time since fire influences the probability of a crown fire. So the effect is small because, if the time since fire is one year for moderate conditions in damp forests, the probability of a crown fire is around 60 per cent.

Senator BACK —Could you take me through that again?

Dr Driscoll —Under moderate conditions in damp forests, as an example, the probability of a crown fire one year after fire is around 60 per cent, from the look of that graph. Then after 10 years it has crept up to what looks like a bit under 70 per cent. Then it goes up a little bit more—probably up to around 70 or 70-something. So, for all the effort and expense of burning the forest every couple of years, you reduce the risk of a crown fire by 10 per cent—from 70 per cent to 60 per cent. So it is not protecting us; it is just reducing the probability by about 10 per cent.

Senator BACK —But if you were to look at that same graph and consider the difference between moderate and extreme, in those same years you jump from 0.65 to 0.85.

Dr Driscoll —Yes. That is the really strong influence of the weather.

Senator BACK —I am trying, perhaps unfairly, to extrapolate this to forested areas in other states. In our own scenario, in Western Australia and I suspect South Australia—I do not know about New South Wales; others in this room would—we would not define a damp eucalypt forest in the summer time in Western Australia. We might in the very, very deep south of the Pemberton karri forests. But, for the forested areas for which we would have responsibility, we would be looking at your higher extreme graph under normal summer conditions.

Dr Driscoll —So the difference between these three graphs is that they are different forest types and it is not so much how wet they actually were; it is a sort of a floristic classification. My guess is that the damp forest—I would have to recheck the report to see how they define their damp forest; it is not really a moisture index, it is a floristic composition—would be roughly equivalent to the karri forest.

Senator BACK —Sorry I am ignorant here. When you say a ‘floristic’ condition, are you speaking of the humidity level?

Dr Driscoll —No, I am speaking of the plant species that are present.

Senator BACK —Do you define some species as damp and others as dry?

Dr Driscoll —Yes. I believe that is what they would have done.

Senator BACK —So we are not talking about whether an individual species, like a eucalypt, was damp or dry; you are speaking about dominance of species which would themselves be defined as damp or dry species?

Dr Driscoll —Damp or dry forests, so the collection of plant species that are present would define a damp forest, and probably Karri forests in WA would pretty well fit a damp forest definition. They have got tall trees, a multistructured understorey—

Senator BACK —Extrapolating from these model predictions, was it the case in the Black Saturday fires that forests that, for example, were defined as damp were not burnt and were not the cause of loss of life and housing and that dry dominated forests were? Is that a conclusion that can be drawn?

Dr Driscoll —No.

Senator BACK —So the damp forests burnt also?

Dr Driscoll —All of those forest types were burnt, yes. That is how we managed to get a range of time since fires for each of the plant communities.

Senator BACK —I will certainly want to go back and read it, but if you look at the position of the extreme and the moderate graphs across B and C—B being the damp and C being the dry forests—it would suggest that for any point in time the probability of a crown fire was actually higher in the damp forests than in the dry forests. I find it difficult to comprehend how a so-called damp forest would carry fire at a higher degree of probability in any year than a dry forest would.

Dr Driscoll —It is not to do with the year; it is to do with the weather conditions. That is what I am saying. The weather conditions really drive the incidence of these dangerous fires. The fires that have stimulated this sort of inquiry, the Victorian inquiry and the South Australian inquiries have all occurred under extreme weather conditions. So, really, considering what happens under mild or low conditions is not very important; it what happens under extreme conditions that is very important. That is why the results emerging from Project Vesta and some of these other studies that have looked at the way the fire behaviour under different fuel loads have not really got to the nub of the problem, because you cannot carry out field experiments under extreme fire conditions.

Senator BACK —That is correct. But I am interested in the fact that, in your five main points, you have not made any reference to fuel loading. We clearly know about a source of ignition. You have made the point about social aspects, and nobody would disagree with that. Ignition is obviously a factor. Oxygen air is a factor and fuel loading is a factor.

Dr Driscoll —Fuel loading is in these graphs, represented as time since fire. So you can assume that fuel increases over time.

Senator BACK —With deep respect, for me anyhow, the contrast between damp and dry does not seem to confirm that, unless you are saying that damp forests are of their nature far more productive—

Dr Driscoll —They are.

Senator BACK —and therefore have far much more fuel loading.

Dr Driscoll —That is right; they do.

Senator BACK —I do not know how I would be helped in coming to make decisions. Given that I think we agreed that you cannot control the weather, therefore in managing you must assume the likelihood of extreme conditions if you are going to protect lives and property, I am at a loss to understand what it is you are saying that is capable of control if not fuel loading.

Dr Driscoll —I am saying that controlling fuel loading may not stop houses from burning down when there is extreme weather. We cannot control the weather, and controlling fuel loading does not help us very much, so we need to consider the other options. We need to be considering those at the same time. So we need to say: ‘Well, okay, maybe sprinklers are going to be a better idea. We can’t control the fuel loading. It doesn’t make much difference to the carry of fire. The extreme weather is what drives it. Maybe we need to stop the houses from burning down, make them more resistant.’

Senator BACK —I am sorry to keep labouring it, but if you are talking probabilities of crown fires at a point anything better than probably 0.5 under extreme conditions—and each of these is better than 0.5—out three or four or five years, they are at close to one. They are at 0.8. They are at 0.6 or 0.7. All of those would put them at a level of risk where there has got to be some intervention by management to actually protect assets. I know you have concentrated on houses and I admire you for doing so. This might sound a bit unusual in the context, but I think there is an enormous amount more to be protected than just houses and lives. I know they are right up the top of the priority list, but, if one looks at the after effects of Black Saturday or the fires here outside Canberra or some of our fires in the eucalypt forests, the destruction of the biodiversity would cause me to put that very, very high on the priority list in terms of protection. The probability of crown fire is such that action has to be taken.

Dr Driscoll —Can I just ask you about that. What gives you the impression that these large intense fires have hammered the biodiversity?

Senator BACK —My observations of the forested areas that have never recovered would suggest to me that we would have been derelict to have allow that circumstance to have occurred. I am not familiar with red gum forests, but the advice that has been given to me from the Victorian situation and here in New South Wales has been that they just do not survive severe fire and do not come back. That would be an example. I can certainly show you examples from our forested areas in Western Australia which were the subject of uncontrolled plus-45 degrees Celsius, eight per cent humidity, summertime fires and the same areas that had been the subject of cool season prescribed fuel reduction, whether it was burning or grazing or other means, in which the variety and the health of plant species was severely contrasted.

Dr Driscoll —To my knowledge, there is very little published evidence that suggests that large fires have such an impact. You should ask Dick Williams about this this afternoon, because he has a paper looking at the influence of the alpine fires, which shows that a small number of species were impacted but generally the whole place is recovering. It is not the intensity or the extent of the fire that has the biggest impact; it is the frequency of the fire.

CHAIR —Have you driven from Cooma to Tumut lately?

Dr Driscoll —Not all the way to Tumut; but I have driven from Cooma up into the mountains.

CHAIR —If you go up that road, you will see—and there are one or two areas where there were low fuel loads—that there is mountain ash from here to that flagpole, 100 foot high and dead as door nails. It has all been burnt. In other areas there is mountain ash from here to that flagpole, as good as gold. It was all to do with what was underneath and what was going on. There are what I call ‘valleys of death’ up there, where everything is as dead as a door nail. With regard to the effect on the balance of nature in these forests between intense and non-intense, you say ‘bugger all difference’—I presume that is what you are trying to tell us.

Dr Driscoll —No, I think, not that there is—

CHAIR —Let me tell you, I rode—can you ride a horse?

Dr Driscoll —I have ridden horses. I mostly ride—

CHAIR —So we rode up through there after those fires for two days. Where the fire was intense, everything is dead. There was not a bird, a worm, a kangaroo, anything. There was nothing. The only live thing we saw were a few wild horses and they had moved a long way. There is a hell of a difference between a cold burn and a catastrophic burn and what it does to the balance of nature. There is just nothing to talk about.

Dr Driscoll —I agree. I think there is a big difference.

CHAIR —But a minute ago you said—I think you said—that it does not matter much. It matters a lot.

Dr Driscoll —What is important is the patchiness of the intensity. If you have the same intensity across the whole landscape then that is going to disadvantage some species and advantage some other species.

CHAIR —Have you ever been to a national park or a wildlife lockup which adjoins mixed farming land? You do not go to fires; I put them out. To get a firebreak in and to stop the head burn, it is very handy to have low fuel loads to do a burn-back. If you are putting a burn-back in—and it might be between two corridors of bush, because not all bush is just trees for 100 miles; there are valleys and things—you are a hero if it works and you are a mug if it does not work, but you have a better chance of it working if you have a low fuel load to work with.

Senator BACK —On the Victorian royal commission: I understand there was a panel discussion on fuel-reduction prescribed burning in recent weeks. Did you participate in that?

Dr Driscoll —No.

Senator BACK —Did Professor Bradstock?

Dr Driscoll —I do not know, but I would be surprised if he did not.

Senator BACK —Yes, so would I. If he did not, I feel he should have. I have not seen the transcript of that particular panel discussion, but my understanding is that there was an overwhelming agreement by members of the panel in support of fuel reduction. You probably cannot speak for Professor Bradstock—

Dr Driscoll —I can speak to that. Amongst the fire ecologists, state government agency staff who work on fire, and fire managers, there has been a very strong culture and belief in the effectiveness of fuel-reduction burning. It is based on trials, experiments and experience under less extreme weather conditions, because you cannot get that sort of experience under extreme weather conditions. You cannot run experiments when it is hot, dry and windy.

Senator BACK —No, but you do have the benefit of actually observing the wildfire behaviour under those circumstances. It is not what you plan to do, but the information you gain is not information lost under those circumstances, is it?

Dr Driscoll —No, we have learnt a lot from looking at wildfires, and that is where a lot of our new learning is coming from—from looking at how wildfires carry through the landscape in relation to fuel loads. It is showing that it carries right through, regardless of the fuel load.

CHAIR —I do not know what experience you have had with fires, but a lot of fires start in reasonable weather. The fire in the Brindabellas started in reasonable weather and could have been put out. It is like a snake catcher: occasionally you are going to get bitten by the snake. They said it was an occupational health and safety hazard to go and put this thing out when it was reasonable weather. Then the catastrophic weather came along and it became uncontrollable. But a low fuel load would have enabled that fire to have been put out, especially when they had planes sitting around with retardant waiting to put it out but they were waiting for a national declaration so the Commonwealth instead of the state funded it, and all that sort of stuff. Do you understand that a lot of these fires that become catastrophic, like these fires in Victoria, start from ordinary circumstances and the wrong weather comes along a few days or a week after they have been going? As to getting control of a fire when you can control it, fuel loads have a lot to do with that. It just makes it so much easier. Do you understand that?

Dr Driscoll —Under certain weather conditions, it reduces the intensity.

CHAIR —But do you understand that a lot of catastrophic fires started off as mundane fires and were there long enough for the right weather to turn up to turn them into catastrophic fires?

Dr Driscoll —I do not know how many catastrophic fires have started in that way. Certainly, the ACT one sounds like an interesting case.

CHAIR —Yes, it was an absolute—

Senator BACK —Part of the role of this committee is to try and advise government on how we should be protecting life and property and the natural environment. How would you conclude your advice to this committee in terms of the objectives we have, considering the information you have put before us?

Dr Driscoll —I think it is really important to recognise that there is a well-established belief that widespread fuel reduction burning is the answer to managing fire, and the disasters that we have had over the last decade show that it is probably not. What my co-authors and I are calling for is for all of the options to be put on the table and for the evidence to be considered.

Senator BACK —Sure.

CHAIR —That is fair enough.

Senator BACK —It is at odds with the experience that we have had, but I appreciate that advice. I will read the paper in more detail. I notice one of the authors is Dr Jeremy Russell-Smith, who has been a close associate of mine for some years. He oversees the annual burning in the West Arnhem Land region, where they have the West Arnhem Land Fire Abatement scheme. Perhaps his experience bears out, in some ways, what you are talking about. In that particular program, if you know it—

Dr Driscoll —Yes.

Senator BACK —the West Arnhem Land group are paid $1 million a year in consideration of the documented saving of the equivalent of 100,000 tonnes of greenhouse gas as a result of early-season burning versus late-season burning, and controlled versus uncontrolled. But Jeremy’s advice to me has been that one of the real winners has been the diversity and health of the plant species in those areas that have been the subject of burning. I know it is a very different mix of flammable fuel there, but that burning occurs much more frequently than three-yearly, so I will be very keen to hear his advice.

Dr Driscoll —I think the burning they are doing up there is working really well. It looks like they have hit on a solution that is a win-win in terms of fire management and biodiversity management. It works really well in the tropical savannahs, but the forests and woodlands of southern Australia are a really different kettle of fish. You cannot apply the same management across the whole country.

Senator BACK —No. I would not for a minute suggest that what goes on in that area should be used everywhere, except to say that the mosaic pattern of burning that has set the principle for that program is very much the pattern of burning that my experience tells me—which I understand independent observations would confirm—that that level of fuel reduction is the most appropriate management tool.

I do not know what I can learn from the material you have put in front of us that would actually help land managers to do what the community expects of them, and that is to protect the community, property and the natural environment from the risk of fire. I go back to that comment: 40-50 to 150 tonnes per hectare is well beyond that level of fuel loading in an area in which, acting reasonably and acting under a duty of care, anybody should ever put people to try and mitigate fire or control fire.

Dr Driscoll —Yes. One of the things I have not mentioned is that also coming out of this new research is evidence that, while burning broadly across the landscape does not seem to have a big influence on how much the adjacent houses get burnt, what does seem to have a big influence is reducing fuel right next to those houses.

Senator BACK —But that is not the Victorian experience, is it?

Dr Driscoll —I do not know what sort of burning they did.

Senator BACK —Crowning was going on some five to six kilometres out—5,000 to 6,000 metres or more—so logic would tell you that burning 100, 200 or 300 metres out would have little impact. If the crown fire, under those conditions—

Dr Driscoll —Under those conditions, you can burn the forest every two years and it will not make any difference.

Senator BACK —I think if you can reduce fuel and prevent the crown fires from actually spotting out that distance, I would take issue. Thank you very much. That has been very helpful.

CHAIR —Thank you very much. We are out of time but we are very grateful for your evidence.

Senator BACK —Can I just ask finally, if I may: based on the advice you have given us and that of your colleagues, what strategies would you use to try and minimise the effect of high-intensity forest fires such as these; what would your advice be?

Dr Driscoll —I would first go through quite a detailed and complex process of considering: how much does it cost to put a sprinkler on everybody’s house; how much does it cost to build them out of things that will not burn? The evidence is that under extreme conditions—we are going to get more extreme conditions under climate change; it is going to happen more often. We have to face that. It does not really matter how much you fuel reduce.

CHAIR —That does not help the pastoral people—

Senator FISHER —Chair, let the witness finish.

CHAIR —and the cattle blokes in between where the fire and the town is. He is focusing on the houses. There are a blooming lot of other things that get burnt besides the houses in town. There are all the cattle and sheep, and God knows what else.

Senator BACK —The engineering solution—

Dr Driscoll —I would go through this decision-making process and seriously consider all of those options: the costs, the effectiveness, the impacts on all of our society’s objectives and then we will have a transparent decision-making process and everybody can say, ‘That’s the outcome. That’s why it was.’ And the decision was not, ‘Are we just going to do more fuel reduction burning because everybody tells me that’s the right thing.’ We have actually got the evidence to support the way to go.

CHAIR —You have not actually told us anything yet of a practical nature.

Dr Driscoll —If you read the paper I have provided, you will see that it is providing a framework for making a decision. Nobody has gone through the process of gathering this evidence yet.

CHAIR —Fair enough, but does it include the well-being of the farm besides the town? Have you thought about what happens on a farm that is in between two forests—have you thought about that?

Dr Driscoll —Of course. The decision-making process is about considering what we want to protect. If we want to protect our farms then how do we do that? I do not know. I was on the Eyre Peninsula the day the fire went off. It burnt across paddocks with sparse stubble.

CHAIR —All of that. A lot of fires start on days that you can do something with them and they spread and they spread and they spread and then they become on the right day catastrophic. Thank you very much for your evidence.

Senator FISHER —Can I ask the professor a further question? I heard him at the end of your response to Senator Back. Doctor, I did not hear you ruling out reduction of fuel load being part of what might end up being the strategy coming out of the sort of work that you are talking about. I did not hear you saying that that is not a consequence. I did not hear you saying that that could not be a result; I heard you leaving the door open that that could indeed be a result once you have done the sort of investigations and assessments you are talking about—is that right?

Dr Driscoll —Yes. My feeling is that widespread fuel reduction burning probably will not be very effective, but we need to consider that more thoroughly. My feeling is that targeted burning in strategic locations next to the assets you want to protect is going to be more effective and, combined with a whole range of other approaches, we might actually avoid the sort of disaster we saw on Black Saturday.

Senator FISHER —Thank you.

CHAIR —Thank you very much.

[1.24 pm]