The Legion Lake fire in Custer State Park this past winter was a challenge and an opportunity. The fire perfectly expressed the competing management and policy objectives swirling around in the smoke of large fire management across the West.
“That was a mean fire,” said one of the initial attack firefighters whose judgment is perfectly sound. It was surprising in its virulence when it started and confounded early efforts to achieve control. Park leadership had one objective, at least at the beginning — put the fire out.
On the other hand, the fire offered opportunities to meet management objectives, perhaps unique in the past several decades. A winter fire is a siren song for fire management. Why not light a lot more country on fire than we might normally, at the height of fire season, and reintroduce fire to a large area of the park where fire had long been excluded?
In the early briefings on the local news, fire commanders offered a glimpse of their thinking. The map of the fire the night it started showed a small red patch in one corner and a huge outline of the chosen method of attack. The incident commander and the park manager planned a large indirect attack designed to contain the fire, a plan that would also burn large areas of the park on purpose.
This indirect approach to firefighting, called “Big Boxing” the fire, is standard issue across the West and is chosen for many reasons. The alternative, anchoring and flanking the fire to pinch it off at the head, is more typical in the Black Hills and is the approach we saw several years ago on the Eight Mile Fire.
Direct attack results in typically smaller fires and limited fire size. It’s also more difficult and intensive, requiring a high level of skill and execution. Indirect attack results in time to construct fire lines and then to burn out from those lines to create black between the fire and control lines. Indirect attack can be difficult and challenging as well, and also requires lots of skill and luck.
The fire lines were duly established using roads and other barriers to contain the burn-outs. Firefighters spent hours with drip torches lighting the edges of roads and burning the perimeter of the big box so that the main fire would run into burned ground and stop, at least if everything went according to plan. The lines of the drip torches are everywhere in evidence driving through the park in the aftermath of the fire.
The big box approach was not unusual although the size of the box in this case was extraordinary for the Black Hills. All went well until a wind even blew the fire out the southeast side of the box, and then it was a fight to contain it. The good news was the fire stayed in the lines over most of the perimeter, as planned.
Hyperbole about the fire being the second biggest in our history did nothing to inform the public about the nature of the fire and the decisions the fire organization and managers made to greatly increase the fire size by indirect attack.
We won’t know what the size would have been if firefighters had gone direct with bulldozers, building a line against the fire edge and burning out the line to hold it. There were reasons for indirect attack that included available resources and other concerns. Indirect attack met many objectives for park management that only a winter fire could offer.
In any event, the park will recover long before the policy questions are settled.