In 1983 I sat on my parents roof watching the Adelaide Hills burn. Last weekend the same thing happened to country Victoria, about 800km away. It was only luck that the rural fringe of Adelaide was spared. We too were right at the end of a record breaking 2 weeks spell of 40C weather, and our peri-urban communities have similar construction and terrain. Population densities in the Adelaide Hills have soared over recent decades due to better freeways and lifestyle changes. I have no doubt that a similar firestorm will occur to the Adelaide Hills in the future.
I am a very junior member of the South Australian Country Fire Service (CFS). As I live in the city I don’t actually fight fires – instead I help out with management and communication tasks at a regional headquarters. Most of the time this means I work radios, for example I have relayed reports from helicopters surveying the boundaries of the fire. I have the utmost respect for the volunteers who actually fight the fires. More senior members of my brigade have 30 years experience fighting fires and now help manage them, for example deciding what resources are required and coordinating logistics.
For a big fire an entire organisation with many levels of management can be constructed in a few hours, live for a week, then be torn down as people return home to their day jobs.
I was very confused about the high death toll (currently estimated at 300) and how people died. You see we have 100 years of experience in bushfire behaviour and have evolved certain strategies based on this experience. Our CFS trainings says that months ahead, you devise a “bushfire protection” plan:
- Decide to leave your home early on the day of the expected fire, several hours before it’s expected impact. You never bolt or try to drive away when the fire is upon you, as it’s too easy to get caught in the open.
- If your decide to stay, shelter in your home and wait until the fire front has passed. Then emerge and either attempt to save your home or move to burnt ground. You prepare months ahead by removing fuel (trees, grass, shrubs) from around your home; having firefighting equipment, appropriate clothing; and be prepared to face the terror of a bushfire.
Remember: Radiant heat is the killer. Deaths directly caused by burning is rare. Put as much solid material between you and the fire. Shelter inside a house. If you are in a car get down low and cover yourself with blankets. Wait until the fire front has passed then move onto burnt ground. Cars and houses usually burn after the fire front has passed. Don’t run or get caught in the open where the radiant heat can get you.
That’s the theory at least, and for normal fires you have a good chance of survival.
However in this was not a normal fire. This was a firestorm:
- Extraordinary weather conditions (46C and high winds) lead to extraordinary fire behaviour. Very fast, unpredictable behaviour. The firestorm could kill by radiant heat at 200m. Fires raced up hills, fanned by their own heat and wind. Trees were vaporised, the gas fuelling the fire. The effect is exponential, 4 times as much fuel makes 13 times as much heat. During World War 2 the same sort of firestorms were generated by intense Allied bombing raids on Germany and Japan.
- Houses caught fire very quickly killing those sheltering inside. In “normal” bushfires, it’s the left over embers that make the house burn, often well after the fire front has passed. In this case home protection equipment was too weak – pipes melted, pumps stopped working, and their power was just inadequate. Houses were on fire in seconds. Glass melted in front of your face. Every fire fighting system has it’s limit, and the firestorm was just too strong.
- Information systems couldn’t cope, people weren’t warned. Information didn’t travel to the people who needed it. I have been in the CFS “war room” when big fires were building. It takes a while to get a picture of what is really going on. You are relying on reports from aircraft or fire fighters via radio. Compared to the progression of a firestorm, information travels slowly both up and down the command chain. The system works OK for longer “campaign fires” that last for a week. You have time to gather information, prepare, coordinate, organise. However I can see why many people weren’t warned in the recent firestorms – their extraordinary speed means they develop too quickly for the system to respond, especially when multiple fires are already raging across the state.
- Decades of rural population growth meant lots of people living in rural environments. Beautiful green trees in winter turn into cans of petrol suspended above your head in summer.
- Fires need fuel to burn. The CSIRO estimates fuel loads were 40-50 tonnes per hectare. About 8 tonnes is considered dangerous. Local government promoted tree planting next to houses. In many cases this was the law. Those lovely trees turn into flame throwers pointed at you and your family.
What to Do
Here are some ideas, most of them borrowed from what I have read this week and some borrowed from much more experienced colleagues in the CFS.
- The old advice still stands. Leave a bushfire threatened area early, or be prepared to shelter in your house and fight after it passes. Firestorms are still not the norm. Put as much between you and radiant heat as you can.
- Shelters (a fireproof bunker) should be manditory, either at household or community level, say at the local park. A $3,000 shelter is a trival expense on a $500,000 property. Get something fireproof between you and radiant heat for 20 minutes and you live.
- In a firestorm situation, allow information to flow quickly to a local level. Each community should have it’s own warning system (like an air-raid siren at the local fire station). Local sensors even, like a web-cam mounted on a pole or local hill so you can see whats coming. Broadcast it at low power on an unused TV channel (or via battery powered wifi) so anyone can see a fire coming. Provide some way for locals to raise and propogate an alarm (for example SMS a certain number to make the local siren ring). Software could determine if the SMS was from a local person with authority to “press the button”.
- Send fire information directly to local areas. For example the perimeter of a fire and it’s direction of travel could be relayed from a spotter plane via SMS to everyone in a certain area. This will allow a plan of escape to be devised, and prevent people driving into the fire by taking a wrong turn. Traditional command and control structures can still be used for medium and long term management of fires. Let the information flow freely, rather than through a chain of command. Locals can then make their own decisions in the event that a state-wide management system can’t cope.
- Fire prone areas could be dotted with sensors, for example small “weather station” type boxes with cameras and cell phones that can detect nearby fires. Hundreds of them. Humans can’t respond on the time scale of a firestorm, but machines could. Place them on electricity poles, houses, hill tops.
- Invaluable aircraft stopped flying at the height of the firestorm (it wasn’t safe). All of our best intelligence on the fire comes aircraft. Remotely piloted vehicles could keep flying under these conditions. Put 10-20 of them up all over the area at risk.
- Fuel load limits should be law and mandated. Could you sleep with explosives spread around your yard?
- Computer games and simulations. I can imagine a 1st person shooter type game where it’s you versus the fire. You get to see the fire approaching your house and try to fight it. You get put in the role of a volunteer fire fighter, or be the head of an entire states fire service. You get to try different strategies and experience their effects (or lack thereof). The games could (and should) be free for everyone to “play” – and get trained in the process.