The SANT LLORENÇ SAVALL FOREST FIRE Operational Report
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Generalitat de Catalunya Departament d’ Interior Relacions Institucionals i Participació Direcció General de Prevenció Extinció d’Incendis i Salvament GRAF The SANT LLORENÇ SAVALL FOREST FIRE Operational Report TYPE OF FIRE S2 Convection fire with southerly winds SYNOPTIC SITUATION Intrusion of hot air masses from south (Saharan winds) BURNED AREA 4.558 ha CAUSE Under investigation RISK LEVEL RISK MAP DMAiH, ALFA o INFOCAT Bombers GENERAL DESCRIPTION MAIN EVENT TIME DATE DURATION Detection 16:53 10/08/2003 Arrival 17:00 10/08/2003 7min Control 19:52 17/08/2003 171 h Extinction 16:00 19/08/2003 22.8 h FIRE BEHAVIOUR DATES Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue PARAMETERS 10 11 12 13 14 15 16 17 18 19 Type of fire High intensity crown fire, with spotting Daily initial 35.937 Potential (ha) Burnt Area (ha) 1.332 1.832 1.394 % of Potential Area/hour 242,18 333,09 253,45 Rate of Fire Max Max Spread Max 33m/min 13,5m/min 6m/min (m/min) Total Area Burnt 4.558 ha Total potential 20000 ha RESOURCES AT SCENE DATES Main UNIT Organization Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue 10 11 12 13 14 15 16 17 18 19 UMC 6 14 12 11 12 8 4 2 1 BRP 57 71 72 66 65 40 19 12 2 BFP BRL 1 1 BUP 6 9 8 7 3 2 1 1 RESOURCES BNP 1 1 3 3 3 1 1 TERRESTRIAL TERRESTRIAL Bombers HOTEL 3 4 4 2 2 2 2 2 1 Generalitat BRAVO 8 9 9 2 2 3 3 VICTORS 6 6 3 MEANS AERIAL GRAF and Professional firefighters 122 174 159 115 102 59 55 34 6 Volunteer 41 57 49 44 29 12 9 6 firefighters Seasonal firefighters 154 210 219 163 93 64 59 38 7 ADF DMAiH COSAR OCA MMA BRIF 1 Pàgina 2 de 23 HIGHLIGHTS The St Llorenç wildfire of August 2003 was one of this years’ large wildfires during summer. This wildfire burned almost 5000 ha in four days and the burned area potential was 20000 ha. This wildfire has affected urbanizations and villages and five people died in this fire. This was the first wildfire that was used extensively with using fire confinement exercises before the fire was extinguished. In this exercise the main key was input provided by the ADF Teams, which produced the required support. The correct assessment and identification of the fire pattern according type of fire and of fire spread at critical points, provided the opportunity to slow-down the fire and to confine it without extinguishing it. For the first time it was possible to avoid the opening-up of flanks during the day or at night during the extreme fire conditions. The main issues to consider: The St Llorenç fire was one of the large wildfires experienced during 2003 with a potential burned area of 20000 ha within a time frame of more than 10 days during conditions of extreme fire risk. The actual area burned, however, did not exceed 5000 ha. This wildfire changed many viewpoints regarding fire extinguishing tasks; especially with regard to the methods of fire management before extinguishing a fire. The 2003 campaign was entered with a detailed analysis of the situation experienced during 1994 and 1998, during other wildfires in Central Catalunya. The main conclusions drawn were that the key to fire control was the control and the capacity of the wildfire to create kilometres-long of fire front, which had to be contained in a continuous manner. The available fire fighting resources were in fact loosing ground against the area gained hourly by the fire, resulting in these resources loosing the initiative to contain this fire. During 2003 the confinement criteria used were based on implementing at each fire type/fire pattern of a treatment that restricted the extension of the fire by “removing the critical points” in order to confine the fire in a specific area In this way this does not grow continuously and the means of extinction won the initiative and can continue their extinction. This involves using maneuvers of confinement of the front of fire or using heavy machinery to stabilize the fire, and then the maneuvers of extinction. This is a cultural change that will take a long time to be assumed despite of to be efficient, because of the using of new maneuvers which looks chaotic by inexperienced onlookers. This change in fire fighting application methods is difficult to understand if you are not understanding how fire extinguishing systems are applied in practice. This new management tool to contain fire (called “fire spread restriction”) is a first step towards handling extreme wildfire situations, demonstrating the potential that forest management and their structures may have to cope with when fighting wildland fires. • Evacuation vs confinement: This fire killed five people trying to flee from this fire coming close to this home. This tragedy reopens the debate on the appropriateness of the methods that can be applied: Evacuation or confinement. By considering the dates of the mortalities that occurred during the past decades one will note that the majority of the victims died while they were trying to escape from the fire. It is necessary to consider this issue seriously and to see what situations are preferred when considering taking the one decision or the other. It is in this direction that we acknowledge the role of essential planning of self-protection of houses in forest environments. This can provide a guarantee to restrict fire spread rather than be Pàgina 3 de 23 forced to evacuate, the latter being rather complicated considering random variables such as weather, traffic accidents, road blockages, and panic situations.... • Towns and urban-interface areas: As a result of an important number of urban communities and areas are being affected by wildfire, including isolated country houses and urban cores within potential fire perimeters. A significant number of fire fighting resources are many times allocated to protect urban areas. Thus in this way resources for fighting wildfires are sometimes severely reduced. • Co-ordination between government and operational fire management: In a fire of such dimensions, extensive co-ordination procedures between the various departments will be involved. In addition, at operating level, the controlling body for such an emergency should organize a strategy that integrates not only the fire fighters, but also their need to include assistance in some way from inside and outside the region for fighting fires, such as rural agents and police. • Speed of extinction: We can differentiate between two different type of speed of fire- line extinguishment/control, thanks to the facilitation of resource placements/movements and with the helpful of the communication channels. The GRAF units (with the light units which collaborate with them) and the aerial fire fighting resources (MAER) were working on the No.18 radio channel at the time, and they were operational, extinguishing the fire at a fast speed. However, the hose lines also contributed significantly to the speed of fire containment, many times extinguishing (finishing-off) a fire perimeter line. It is necessary to refer to an important directive, drawn up by the GRAF units to move and assist in locating various different resources, from Bombers to external teams (e.g. volunteers units and ADF). This resulted in some profitable coordination and work co- operation, as it was now possible to introduce combined tasks of opportunities and to locate resources/teams faster to fire areas. With reference to controlling the fire with volunteers, it is necessary to mention that all the information about these participants should be collected before hand, such as where they are working for, and who will be in charge when contacting them (Incidence Command System). It was also found to be important to change of work strategy at night-time. To ensure that a wildfire doesn’t spread uncontrolled during the night, it is necessary to see to it that people continue to work and to use the evening hours to advantage, to finish-off and to stabilize the fire perimeter. Pàgina 4 de 23 GENERAL ANALYSIS Fire Weather Conditions The drought: For reference we can compare the 2002 with the 2003 drought. As one can see, the drought indices in 2003 are higher and more extensive than in 2002. This also includes the higher drought accumulation rate during the period between July 20 th th and August 15. In addition, in 2003 the spring-time 11 of august 2002 11 of august 2003 Figure 1:Drought Code Maps period was very wet. Synoptic map 850 hPa (temperature) This wildfire episode was caused by the wave- action from the south that was above Catalunya and which produced overheating and a fast drying rate of the vegetation between August 13 and August 17. This situation led to high temperatures above normal conditions and a low relative humidity, which made the fuel as good as permanently “available”. This period of 15 days, was the main cause that the situation created was very explosive with an almost constant available fuel Figure 2. Temperature to 850 hPa. Warm and dry Saharan air mass above Occidental Europe. Font: pattern throughout the landscape. www.wetterzentrale.de/topkarten Window of Large Forest Fire One of the most important aspects of these heat waves, is the recovery of fuel humidity during the night. This is the most significant feature and marks the full availability of uncontrolled burning of vegetation day and night, without any problems, creating the opportunity for the wildfire to grow continuously.