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Dedication: This publication is dedicated to the men and women who fought the fires of December 1993 and January 1994, and to the thousands of other volunteers who stand ready to assist their communities and the people of NSW through their dedication and commitment to the NSW Rural Fire Service. Text: Copyright NSW RURAL FIRE SERVICE Unit 3, 175-179 James Ruse Drive Rosehill NSW 2142 Ph: 02 9684 4411 Fax: 02 9638 7956 Illustration: Copyright NSW RURAL FIRE SERVICE Printed January, 1998 ISBN 0-7311-0895-7 Foreword. This publication is designed to place in context the events of December 1993 and January 1994 and to shed some light on the interaction between communities and their environments. Many communities were faced with a fire threat the like of which had not been experienced for at least a decade, with many people having never experienced such a fire storm before. Whilst some accept that fire is a natural and beneficial aspect of our environment, many people take this force for granted and consequently do not prepare for these events. It is in the nature of "disasters" that they fade from public memory quickly. This is an attempt to return to "normality" as soon as possible, and yet, if we fail to learn from these events, we will be as unprepared as ever. Thus we are seen as victims of these occurrences. Unlike floods and cyclones, fires can be prepared for, prevented or at least their impact can be substantially reduced if we accept the need to plan for these events. The fire history of the areas impacted upon in 1993-94 is well understood. Traditional fire paths that is the course that fires take, have been plotted over many years and we can predict the likely behaviour of fires given the weather conditions, the topography of the area and the amount of available fuel. Why is it then that communities remain uninterested or unaware of the potential dangers of fires and do not undertake simple but effective strategies to protect themselves and their homes? The interactions between communities and their environs are both complex and dynamic. So too are the forces which contribute to fires of extreme intensity as witnessed in 1993-94. This publication provides some essential facts of these dramatic fire events. Careful consideration will reveal how people responded to the emergency and what fire authorities and governments can do to be even more prepared in the future. Whether the public will be better prepared for the next significant fire event is difficult to predict. Fire authorities generally and the NSW Rural Fire Service in particular, are working hard on community based fire prevention and protection programmes which will go a long way towards ensuring that individual house holds are better prepared. A range of other programmes supported by many brochures and pamphlets seek to spread the message of fire safety. Ultimately fire is everyone's responsibility. As Australians we MUST accept that fire is a feature of our forests and grasslands. If we can gain a greater understanding of the part fire plays in the environment and how this force will impact upon our communities we will have gone a long way to accepting our individual responsibility in this complex and dynamic interaction between people and where they live. Introduction __________________________________________________________________________________ In early January, coastal New South Wales experienced an extended period of extreme fire weather, north of Sydney to the Queensland border and south of Sydney to Batemans Bay. The areas primarily affected included the coastal plains and nearby ranges. More than 800 fires started between December 27, 1993 and January 16, 1994. The total area burnt was 800,000ha. Intrusion by fire into Sydney and nearby metropolitan areas occurred in a manner never before documented. All areas burnt had been subject to previous wild fire, but never before had they burned simultaneously. The fires seemed to be everywhere across the State and yet the area burnt represented only 1% of NSW. The Headquarters of the then Department of Bush Fire Services became the focal point of the operation and resources were rapidly marshalled from every State and Territory in the Nation. International resources from New Zealand were utilised. Defence forces assisted in strength. At the height of the campaign about 20,000 personnel were deployed on suppression, life and property protection and support activities. Despite the extent of the fires and their severity, particularly in and near the large urban areas from Sydney to the Blue Mountains and the Central Coast, losses were remarkably light. Tragically, one civilian and two volunteer firefighters lost their lives. In total, 206 homes, mostly in urban areas, were totally destroyed. Many others sustained minor to severe damage. The low level of loss under the conditions which prevailed is testimony to the skill, courage and untiring endeavours of the many emergency services personnel and others who played a role in life and property protection, and fire suppression. Despite the low level of loss, death and injury, there is no room for complacency. Fires similar to those of 1993-94 will occur again. The community must be prepared for this eventuality. One aspect of being prepared is to understand the dynamics of this protracted fire event. This publication sets out to document this period of fire activity which resulted in the greatest A State Ablaze firefighting effort in New South Wales history. It discusses the causes, the aftermath and what happened during that period which has left an indelible impression on the minds of those involved. It also examines the environmental impact and legislative changes that have been introduced since the fires. Note: During the 1993 -94 bush fires our service was called the NSW Bush Fire Service. Since 1st September 1997 a new Rural Fires Act was proclaimed. Our service is now the NSW Rural Fire Service. (see page 27 &28) 4 Weather Weather conditions play a significant role in the behaviour of bush fires. Temperature, relative humidity, wind speed and direction, atmospheric stability and rainfall are significant factors which influence the way fires behave. They have a direct impact on the fire's ability to spread and consequently play a crucial role in defining the ease or otherwise of the fire suppression task. Temperature It is not possible, even on the hottest of days, for the sun alone to raise the temperature of grass and forest fuels to their ignition points. It requires the addition of an ignition source. On days of high temperature, however, the fuel is pre-heated to a stage which is closer to its ignition point and will be easier to ignite from another source. During periods of high temperature, water moisture in the fuel will be evaporated into the air, providing conditions of low relative humidity exist. (See RH). Temperature may also influence or be a factor of atmospheric stability and wind speed and direction. Relative Humidity (RH) The amount of water vapour in the air is measured as a percentage. For example when the RH is 100% the air is said to be saturated and will not absorb any more moisture. During periods of high humidity, fires will not spread as quickly because fuels contain a high amount of moisture. Conversely during periods of low RH, (below 30%) fuel moisture levels will be low and when exposed to high temperatures will continue to release more moisture to the air. Consequently fires will spread rapidly, spotting commences (burning material blown ahead of the main fire front starting new fires) and crown fires (fire in the uppermost part of the trees) may develop. At less than 20% RH fire behaviour becomes erratic (in combination with other elements) and less predictable. 1600 WIND SPEED C A - Calm B - 15km per hour Rate of spread (metres per hour) C - 30km per hour 1200 800 B 400 A 0 25% 20% 15% 10% 5% 5 % of moisture in fuel (fuel moisture between 4-6% is critical) Clouds Clouds shield fuel from direct sunlight which will result in fuels having a higher moisture level than if they were in direct sunlight. In a forest, fuels exposed to direct sunlight may have a moisture content 2 - 3% lower than fuels in deep shade. A similar situation exists with extensive cloud cover. The absence of clouds will expose fuels to the direct rays of the sun allowing a greater amount of fuel to dry out. The Effects of Rain Following periods of rain, fuels will have higher moisture levels. When this coincides with moderate to high temperatures, humidity levels will also be high and consequently fires either will not burn or will not burn as readily. The longer the period since the last rain, the lower the amount of moisture in the fuels. Some fuels, such as grass, may dry out in a matter of hours following rain, under the right conditions. If the moisture level of fuel is low due to periods of prolonged dry spells or drought, fire intensity and consequently fire behaviour becomes extreme. The bush fires in NSW of December 1993 and January 1994 were examples of extreme fire intensity which was preceded by prolonged drought, high temperatures and low RH. Wind Effects Bush and grass fires are driven and spread by wind. It is therefore the most important weather element affecting fire behaviour. The two main elements of wind effect are (1) DIRECTION and (2) SPEED. Wind also contributes to the effects of spotting. A State Ablaze 6 (1) Direction Winds on NSW east coast and tablelands from the north, north west through to the south west are dry and hot during summer.

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