Thursday, February 26, 2009

Preparing for Wildfire

This post focuses on the factors that we believe helped save our place and includes aspects of our permaculture design intended to reduce the threat, as well as what we learned from our recent experience. Comments relate specifically to our location and personal observations, and may not apply under different conditions.
House designOur house is mudbrick with small amounts of exposed timber and built on a slab. Embers blown up against the exposed slab are easily spotted and extinguished. Exposed timber surfaces are smooth so embers blow off. We kept the house profile low so that a firestorm’s embers and radiant heat would largely pass overhead. Before and during the fire we continually wetted down external surfaces-especially vulnerable parts of the roof structure. The eastern wall is earth covered, giving that wall more protection and allowing us to gain quick access to the roof.
On the northern side (the most likely direction of a firestorm) the bulk of the forest is 80m away. We located our dam and vegetable patch between us and the forest to create a low risk buffer. As fires tend to race up slopes we built our house on an area with a low gradient. Our orchard is located to the northeast of the house providing another green buffer and a wide driveway with cleared sides provides a firebreak to the west and south. This photo is taken from our roof looking north. The burnt forest can be seen on the other side of the dam.
Breaks in vegetationWe do have extensive areas of native plants including some eucalypts close to the house. However these plants are broken into groups with breaks between them and we have generally focused on low risk plants like grevilleas, wattles etc. We mow under the bigger trees and remove potential fuel such as sticks. These areas are thoroughly wet down during risky periods.
The Bush
We gather fallen timber for our wood stove and wood heater and burn fallen timber in areas close to the house, to reduce potential fuel levels.. In our experience trees were not a major problem. The fire raced along at ground level with an intensity related to the amount of fuel available on the ground. It did tend to race up trees with fibrous bark (stringybarks), but if there was not a lot of heat generated from fuel at the base it tended to fizzle out once it reach 8-10 metres without igniting the canopy (see photo). We put a lot of effort into hosing or bucketing water onto tree trunks, because most wind-blown embers came from up higher up the tree trunks.
Many native plants did not readily burn. These included wattles, tea tree and smooth trunked eucalypts. These plants were only vulnerable where there was a build up of fuel on the ground. This photo shows how the fire burnt all around a patch of titree without igniting it.
Some people advocate the removal of all trees in the vicinity of the house. This may have several detrimental effects which should be taken into consideration:-
· The fire travelled fast across the open grasslands, but seemed to slow down once it arrived at our heavily treed block. Perhaps the trees and thick undergrowth slowed the wind.
· Trees may provide a shield against radiant heat and deflect that heat upwards.
· The foliage of trees can catch embers, perhaps reducing the amount being blown at the house.
· Trees have many benefits for humans and the environment, unrelated to fire.

The other point we would like to make in regard to people who wish to remove all trees from their land is, why are they buying bushland properties in the first place? Surely if they have a desire to live in a cleared area that’s the sort of block they should be buying. They should also be aware that many houses located in paddocks burned to the ground.
Bare earth, paths and tracksThese proved to be very valuable in stopping the spread of the fire. Our drive sweeps around the edge of the bush providing some protection on the west, south and east of the house. As our soil is very poor, there are various areas where there is no vegetation at all. (Poor soils have their benefits.) One of these areas is where we built our solar array. Of course it is wise to ensure grass is mown short in critical areas such as around tanks, pumps, sheds, the house etc. Surprisingly a sawdust path was enough to stop the fire creeping along. (see photo).
Water supply
Adequate water and a guaranteed supply are essential to defend a property. In a firestorm, town water is likely to be unavailable so an independent supply is required and preferably from two or more independent sources. Mains power is likely to go off so pressure pumps may not work. All pipes must be safely buried and protected where they come to the surface.
We have two independent water reticulation systems with multiple water sources supplying each system. Our large dam feeds into our garden watering system via fire pump. Above the house a small header dam feeds into the same system. In all, the two dams hold 5 megalitres of water when full, and we used only a fraction of this to fight the fire.
Our other water system is 80,000l of drinking water held in four tanks. An electric transfer pump (powered by our independent system) is used to shift water to a header tank giving us good pressure in our house taps. If the pump should fail, we still have a low pressure supply from 2 tanks that are positioned higher than the house giving us a head of about 5 metres.
We saved the header tank in the bush by keeping fuel loads around it low and by pumping till it overflowed dampening the area around it.
Thirty taps are located strategically around our infrastructure. One set is close to the house, another set is about 15m away and a third set provides water to edges of the area we intend defending. Most of our taps are fed by 50mm pipes with 25mm rises, reducing friction and maximising flow rates.
We have a mix of hoses that we have collected over the years. We are gradually switching to 20mm diameter hoses and standardising fittings to make it easy to switch hoses between various taps. We do have 2 fire fighting hoses which are very useful for delivering large quantities of water or throwing over a distance. Having at least one very long hose (30-50m) allows the fire to be attacked well before it gets close to the house (if it is safe to do so). Having plenty of hoses is useful because shifting them around is time consuming, risks damage and is hard work.
Power supplyIn an emergency, mains power is likely to be lost, so this should be taken into consideration. Having our own solar supply was useful, but it meant we had an extra asset to protect. We also used our petrol generator because we were running our electric transfer pump for extensive periods. As this photo shows, the fire came to within 10m of our solar panels and generator.
Fighting the fire
Fortunately there were four of us fighting the fire. This allowed for two to protect the house and two to focus on further out areas and to look after anything else that cropped up or needed doing (eg supplying drinking water to people on hoses). Less than four would have made it a more difficult job.
Speed of ApproachFires can move quickly. Even though we had an hour's warning, we did not have enough time to fully prepare. Everywhere we looked, there were jobs that needed doing. Jobs that we had been intending to do, but never got round to doing. Some that come to mind are raking up leaves in vulnerable areas (leaf build up occurs every few days in dry conditions), fixing a broken hose, weeding around taps, buying extra smoke masks and having standardised hose fixings.
Prevailing windAlthough it was the wind (southerly change) that brought the fire to our place, in some respects the wind proved helpful. Once the fire had passed the house, the wind pushed the fire front northwards. It kept expanding on the sides but at slower pace, that was easier to fight. The other advantage of the southerly change was the fact that it was cooler. In fact, none of us have a clear recollection of overbearing heat- although it must have been hot at times.
In southern Australia the hot blustery northern winds are usually the cause of destructive fires, and this was the direction we expected the fire to come from. However our plan also considered fire coming from other directions, as was the case this time.
Broad Scale CalamityThe speed of the fire combined with the fact that dozens of fires were erupting concurrently, meant that no matter how efficient the emergency services and media were, there was no way they could provide 100% accurate local information in real time, nor could they help every property owner. Do not expect emergency services to help you- of course if they do that’s a bonus.
Protective clothingWe had the following in our “Fire Fighting Box”.
· Several pairs of cotton overalls and hats
· Masks designed to filter out smoke particles (P2 paper masks with valves). Have enough spares in case they break or get clogged.
· Goggles- smoke in the eyes is blinding and particles become painful
Boots- strong lace up leather boots are also desirable. Gum boots can melt on hot coals.
The CFA have excellent guides listing jobs that need doing. As well as the obvious stuff, a regular inspection of infrastructure is wise. Check out all pipes, taps and dam stop valves, clear around tanks, pumps and other critical infrastructure. Have generators, chainsaws, pumps etc all fuelled up and test run them on high danger days. Plenty of fuel and spare spark plugs are a good investment.
Wet down and keep wetting down critical areas but take steps to stop dam water contaminating drinking water. Have a plan of what you are going to do about animals and do it early. We brought our dog, corella, guinea pig and some chooks into the house. Apart from the dog they were safely shut up in suitable boxes with feed and water.
Fire PlanWe had a carefully thought out fire plan. Each year we revised it, to take into account new factors. The plan details what needed to be done and when. Although we hadn’t completed 100% of our tasks, once the fires started we knew exactly what needed to be done.
Stay and fight or Evacuate?The key question in a fire plan is whether to go or stay. We had always planned to stay, but as it turned out, we had no choice on the day because the fire came from the south- the only escape route we had. This highlights the importance of leaving early if that is the chosen option, and early means the night before a dangerous day or early morning at the latest. We know neighbours who had intended leaving, but the speed and ferocity of the fire prevented them. Although they lost their house they were able to shelter in a wetted down area and were eventually rescued by the police.
The choice to stay should not be taken lightly, and only if adequate preparations have been made and the property is defendable. See other notes for our ideas on what we believe is necessary to defend a property. We are still horrified by talk back radio callers saying that they intend leaving early - "as soon as they see smoke". This is far too late. There are numerous instances of people being caught on the roads. Even a distant fire can reduce visibility to dangerous levels.
GardensGardens were part of our defence plan. Our large well mulched veggie patch is to the north. This was kept wet during the whole ordeal and the dampness caused any embers that landed here to quickly extinguish.
The house itself is mostly surrounded by areas of mown grass and our gravelled drive so there was very little fuel near the house.
Property designWe were fortunate in that we had completed a Permaculture Design Certificate Course in 1995. Although this is fundamentally aimed at developing a property plan for sustainable and energy efficient living, it also covers consideration of defence against wildfire. As we developed our property plan, fire defence was a significant factor in our decision making. Improving our PreparednessNow that the fire has passed through, fuel load in our area has been massively reduced and the risk of wildfire should be low for a few years. However each year after that, the risk will increase. We have already started planning on how we can make this property even safer. Our ideas include:-
· Extra taps in some areas, and a sprinkler system on the house
· Expand the clearing around our solar system
· Replace 12mm hoses with large diameter hoses and position at least one extra long hose on each side of the property
· Remove all sticks and sapling growth within 30 metres of areas we wish to protect, before summer and maintain this during the fire danger period.
The CommunityAs the saying goes “no man is an island”. We are all part of a community and if our community is better protected, then our risk is also reduced. Our local fireguard group under the guidance of Serafina (CFA representative) helped us develop awareness of fire behaviour and helpful strategies. We also gained a better understanding of the broader risks and Serafina (just a few weeks before) took us through what happens in a wildfire situation, which meant we were much more prepared mentally for such an event.
Another aspect of community, is the risk posed from neighbouring properties. Our fire came via the surrounding farmland. Perhaps strategically ploughed firebreaks may have slowed its progress. In built up areas, if one house catches fire it would be very hard to protect other houses close by. Hopefully when communities are rebuilt, communal strategies will be developed that protect groups of houses (eg a large communal store of water with a reliable fire pump)

In summary, we consider these factors to be critical before staying and defending property
· Ensure children and others who are not capable of actively fighting the fire evacuate before any risk arises. (eg day before)
· Adequate independent, fail proof water supply available on all sides of area to be defended
· Develop fire breaks and green buffers around each side of the house
· Independent power supply, if power is critical
· Protective clothing for everyone
· Prepare the property before the fire season, keep it prepared and be on guard on high risk days
· Have a carefully thought through fire plan with back-up plan for a worst case scenario
· Join a local fireguard group and/or liaise with the local CFA. Knowledge is power.
· Minimise fuel loads at ground level in areas to be protected.
· Protect vulnerable parts of the house- eg build on a slab and close up points of entry to the roof space.
FOOTNOTE We run regular small group tours of Tenderbreak Permaculture Farm. See our Blog post dated Jan 9, 2009 for more details. After the fire danger period is over (hopefully very soon) we will start running these tours again. On the tour we normally explain our bushfire preparations, but this year there will be an added dimension- detailing what worked and what could be done better. If you would like to be kept informed about dates for these tours or would like more information, email us at

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