C which is very hot for late in the morning, with a very low humidity and winds from the northwest around 40km/h – the ingredients for extreme bush fire weather. Sure enough within 30 minutes the thin smoke plume had grown to the scariest thick black smoke plume I had seen only a short distance ahead.
Around this time the Western Australian Department of Fire and Emergency Services water bombing helicopters started to appear and soon after an emergency fire warning was received on my mobile phone – warning of the impending danger posed by what has since become known as the Perth Hills or Parkerville bush fire. Within a few hours 55 houses has been totally destroyed but thanks to the very fast response of the emergency services around another 500 houses that lay in the path of this fast developing bushfire were saved. The severity of the fire can be seen in the photograph in Figure 1. Fortunately no lives were lost in this bushfire although the Insurance Council of Australia’s figures show the insured losses for this bushfire were around $88 million in 2014.
Although small compared to the most devastating bushfires in Australia’s history it serves as a reminder just how quickly a
hot summer’s weekend day can turn a day of relaxation and family activities into one of community wide loss and trauma within the space of a few short hours. This is despite the modern fire fighting technology at the disposal of the fire agencies. With conditions like those experienced on this day when temperatures peaked at 44o
C with 40km/h winds, bush fires become uncontrollable.
Unlike other natural disasters such as severe thunderstorms or floods the risk of a total loss – the entire building and everything inside and outside the house – family photos and mementos gathered over the decades, clothes and other personal possessions, cars, caravans and so on - is a real possibility. And sadly on too many occasions lives are also lost. The most devastating of all of Australia’s long history of fires were the Black Saturday fires of 2009. These fires killed 173 people, destroyed around 2000 homes and burnt out 4,500 km2
of land, leading to insured losses of $1.09billion (ICA – 2009 dollars). Other very memorable fires in history include the Ash Wednesday fires that affected SA and Victoria in 1983 and the Black Tuesday fires in Tasmania in 1967, not to forget the many serious bushfires that have affected large areas on NSW over the years, including earlier this year in the Blue Mountains, and of course, our national capital, Canberra, in 2003.
A post analysis of the losses of houses compared to the distance from vegetation was very revealing. Although for most bush fires the houses within 100m of bushland are most vulnerable, the Roleystone and Duffy (Canberra) bushfires show that even houses as far as 500m from bushland can be lost in major fires. Sparks from the main fire front can trigger house fires hundreds of metres ahead, particularly if there are leaves in the gutters, dry vegetation around the houses or they have evaporative air conditioners mounted on their roofs. So bush fires can be seen to pose a significant risk to hundreds of thousands of households around Australia. To assist home owners to protect their properties from bush fire the WA DFES have prepared a comprehensive guide to the damagers bush fires present to households and steps the home owners can take to protect their homes and property. This includes setting up building protection zones, as illustrated in Figure 2. The width of the bushfire protection zone also depends upon the slope of the property. For flat land the protection zone should be at least 20M but once the slope increases to over 20o
the zone needs to be expanded to 40m or more. The full DFES document can be found here
.Figure 2: Diagram illustrating the various fire protection zones for properties adjacent to bushland. Source: WA DFES.
Bush fires have been a part of the Australian landscape since pre-historic times and it is an ecological fact that naturally occurring bushfires are a factor in the maintenance of our ecosystems. Naturally occurring bush fires are caused by lightning strikes and many of these occur in what would be described as only moderate fire weather conditions. However permanent ecological damage occurs when bush fires rage out of control on days when extreme to catastrophic fire weather conditions occur. The fires kill even mature trees, outrun all native wildlife and also exceed the capabilities of our hard working fire agencies to contain them and protect personal life and property. Compounding this are the increasing number of non-natural causes of bushfires, ranging from deliberately lit fires to problems with power poles and lines to discarded cigarette butts and to sparks from machinery or vehicles. Therefore there are many more bush fires for the fire agencies to contend with than occur from purely natural causes.
With our changing climate the risks of an extreme or catastrophic bushfire are rapidly escalating. Bushfire risks are multi-factorial and so precisely defining the changing risk is geographically quite variable and depends upon preparedness of communities and the level of equipment and personnel of the fire agencies amongst other things. However the rapidly increasing maximum temperatures illustrate the rapidly increasing extreme bush fire risk. For a business as usual climate change scenario, a representative Australian climate model (Access 1-0) predicts the number of days with maximum temperatures above 35o
C to soar by 2030. For example at Wangaratta in NE Victoria the days are likely to climb from their historical 19 (for the 1981-2010 period) to 29 (2016-2045 period), Canberra should climb from 7 per year to 12 and Dubbo (NSW) from 31 per year to near 51. (See www.climatechangeaustralia.gov.au
for more details).
Insurance required to protect businesses and personal property
This escalating bush fire risk, particularly in an El Nino season, makes having adequate insurance to protect yourself – covering all forms of potential loss - essential. As well as home and contents, motor vehicles, caravans, boats and other valuable items kept in properties potentially at risk of bush fire damage also need to be insured. Yet the sad fact learnt from the Victorian Black Saturday fires is that an amazing 80% of people affected by these fires were not adequately insured. This is a salutatory lesson for all – full insurance in the many fire prone regions of Australia is essential.
Business interruption following a major bushfire event can also be substantial. Even if a business is not directly impacted by a bushfire the prolonged loss of power and communications is a real risk. These services are among the first to be affected by major bushfires and can take weeks to restore.
At around 11AM on the morning of 14 January 2014 as I drove from Northam (WA) towards Perth a narrow plume of smoke rose in the distance above the Jarrah forest canopy. As a former fire weather forecaster in the Bureau of Meteorology I was immediately concerned. It was a very hot day, around 42