Fighting Fire
When the first tendrils of smoke curl up out of the grass or brush, a phenomenon called a wildfire is beginning. I recently had the unique, and somewhat frightening experience, of seeing a rather persistent fire start inside my house. Fortunately, I was able to grab a fire extinguisher and quickly control the blaze. In my case, a small extinguisher, quickly applied to the base of the fire, brought the flames under control. However, when the whole outdoors is burning putting out the fire requires a totally different approach and a much greater magnitude of effort.
The report of a fire in our local foothills triggers not only the dispatch of several wildland engines with firefighters aboard, and usually the local bulldozer on its transport. Plus, in recent years it also includes the launching of at least two air tankers from the Porterville Base. This may seem almost an “overkill” response to a small spot fire in the hills.
If the fire area is accessible and the point of ignition isn’t too remote, when the engines arrive a few gallons of water are sprayed and the fire is quickly brought under control. The first engine arriving sizes up the situation, and if possible, the dozer and the aircraft are canceled and told to return to base. However, when accessibility is limited because the fire is high on top of a ridge or mountain, or if the wind is pushing and enlarging the blaze, suppression is going to take more than a couple of engines and a little water.
As soon as the dozer arrives, it begins cutting a swath of bare earth along the side of the blaze. When the fire reaches the bare ground as it burns toward the dozer line, with no fuel to consume, it should stop. However, conditions may afford it the capacity to leap a dozer line or roadway, related to large amounts of fuel and/or wind. But wildland engines, capable fire crews, and dozers, aren’t the only tools available to the business of putting out fire. With the advent of the air tanker and helicopter into fire suppression, the whole picture of putting out fires has changed.
Many years ago, several different kinds and sizes of WWII bombers were converted to fire use. Because of the high cost of operation of all aircraft, it took many years of only occasional deployment, before the rapid control of smaller wildland fires made their use cost effective. Today, the dispatch orders for wildland fire almost always include the use of either tankers, or helicopters, often both. They also dispatch another aircraft, one meant to circle overhead and act as a sort of “control tower” for the tankers, with bellies filled with retardant, and helicopters with baskets or buckets hanging underneath.
In many instances, the basket of a helicopter can be dipped in a nearby pond, lake, or stream, which fills it with water, to then be carried to hot spots to assist the firefighters to gain control. If desired and needed, an MRB, or a Mobile Retardant Base, can be set up in a clearing or flat space nearby. The helicopters dip their basket, with the bottom wide open, into a large container of retardant, then carry it to the fire.
We all have a pretty good picture of the actions of the tankers, flying low over the fire, dumping a huge stream of retardant in a colorful orange plume. There are even “Super-scoopers” that skim the surface of lakes scooping water into their tanks, then dumping their load on the fire.
Roads of all kinds and sizes, rivers large and small, and even narrow streams can also be used to help control, and ultimately contain the fires. If the fire can be prevented from “jumping the road” or “crossing the creek,“then a road, river or creek itself may become the needed firebreak. Once the fire is extinguished along the edge, careful attention must be paid to the smoldering twigs, sticks, and even cow manure patties, along the edge, before control and ultimate containment can be gained.
When a wildland fire is burning in the forest, often the understory brush and grass burn uninhibited. As the grass burns, the brush may ignite. These “ladder fuels” take the fire higher and higher, eventually catching the trees themselves on fire. At first, “individual torching” of trees occurs, with one tree at a time flaring up into a searing hot candle of fire. If enough individual trees ignite, what’s known as “crowning,” or a “crown run” may be the result. When this happens, multiple trees, sometimes entire hillsides, will simultaneously ignite in spectacular fashion.
Of course, underneath these burning trees, the understory of brush or grass has burning embers cascading out of the burning treetops, igniting it all. But not all trees or forested areas, will be subjected to crown runs or even somewhat limited individual torching. Sometimes the brush and grass burn slowly enough the ladder fuels of taller brush, don’t get burning hot enough to ignite the crowns of the trees above.
The responsibility of the firefighter is to bring the blaze first under control, and finally under containment. And there exists two misunderstood words. To bring a fire under control, the edges of the fire should appear to be out with no flame visible along the edge, and the fire shouldn’t be expanding. Just because the fire is under control, doesn’t mean the firefighters can leave and return to the station to await the next call. The entire fire must be first contained before they can leave and be sure the fire will remain out.
To be contained, there might be a line of bare earth, thoroughly wet down fire line, or sometimes a line of retardant around all edges of the fire. Of course, there can be a combination of all of the above, including a hose line strung around the edge. Fires in contained status are assumed able to be left alone by the firefighters.