Fire
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A plume-dominated fire, more commonly known as a fire storm, is this same cycle writ large. In this case the three legs of the fire triangle not only provide the conditions for fire but amplify one another in an apocalyptic feedback loop—a “synergistic phenomenon of extreme burning characteristics,” as it is known. As in all fires, heat generates wind, which makes the fuels burn hotter, generating more wind. If a high fuel load is introduced into this loop, a convection cell of smoke and gases can be set in motion that overrides the local wind patterns. During World War II Allied bombers intentionally started fire storms in the German cities of Hamburg and Dresden; in that case the high fuel load was densely packed houses ignited by thousands of tons of ordinance. Once the convection engine has started, it is nearly impossible to stop. Entire stands of trees torch as one. Tornadoes twist through the interior of the storm. Superheated fuels appear to combust spontaneously in a phenomenon called “area ignition.” Such a fire can rip through well over one hundred thousand acres of timber in one day.
Another sort of apocalypse, equally destructive, is the running crown fire. Crown fires occur when flames climb so-called ladder fuels into the treetops and are swept along by high winds. In 1967 a running crown fire crossed the Idaho panhandle on a four-mile front that incinerated sixteen miles of timber in nine hours. The Sundance fire, as it was called, was calculated to have burned at rates of up to 22,500 British thermal units per square foot per second. By comparison, 500 Btu is the outer limit of what humans can control; 1,000 Btu describes potential fire storm conditions. The Sundance fire was estimated to release the energy equivalent of a twenty-kiloton Hiroshima type of bomb exploding every ten minutes.
Not all big fires are fire storms, of course, and not all fire storms are big. The Steep Creek blowup on the Lowman fire had the physical characteristics of a fire storm but was limited in area; the Foothills fire developed several convective columns over heavy timber but went on to become a wind-driven fire that ripped through two hundred thousand acres in two days, making it one of the biggest fire runs ever. In the Northern Rockies there are a host of winds that push fire: jet stream winds that drop down over mountainous areas; chinook winds that plunge downslope because of an air pressure differential; cold fronts that move in for twenty-four hours at a time; and, of course, unstable air associated with the fire itself. Unstable air rises and falls with the atmospheric conditions, whistling up canyons, sheering over ridges, bending around solitary trees or boulders to start whirls up to four thousand feet high. Any of those winds, in the wrong situation, could cause a blowup and kill people. That was why Mike Rieser was on a ridgetop watching the clouds rather than down in some canyon fighting the fire.
Hotshots have been known to complain that overhead—the men and women who risk other people’s lives—do not do enough. Not only that, but hotshots believe that many overhead have never really fought fire and therefore can’t be trusted to make life-and-death decisions. Sometimes that is true; there are the inevitable instances of ’shot crews simply saying, “No, we won’t go in that canyon,” or, “No, we won’t try to hold this ridge.” More often, however, the members of a command team, like Rieser, have worked their way up from grunt-hood to positions of authority over the course of years, if not decades. Rieser has fought fire for nearly twenty years and had two extremely close calls (that he told me about). Once he and his crew fell asleep after cutting line all night and were almost burned over; another time he was caught in a chaparral fire outside Los Angeles. Chaparral fires are extremely volatile because, invariably, the fuels are bone dry, the terrain is steep, and the winds are terrible: Santa Anas that hit seventy miles an hour for days on end. It was in 1979, and Rieser was on a type two crew that, he says, had violated just about every watch out rule in the book.
“We were backfiring off a road two-thirds the way up a ridge,” he said. “We couldn’t get a good burn because of a marine air intrusion. We double-shifted into the next day and got a dominating Santa Ana wind, and the fire just blew up. We were right in a canyon, it was acting like a natural chimney, and the flame front was on us in about ten minutes.”
In those ten minutes the crew managed to jump onto a tanker truck and make it to a marginally safe area at the intersection of two dirt roads, not big enough to qualify as a legitimate safe area but better than nothing. They parked the truck and crouched down between it and a road cut. The crew were so rattled that they were reading the Spanish side of their fire shelter instructions, not understanding a word. While the rest of the crew were trying to figure out their instructions, the fire went through.
“It was so loud that we couldn’t even shout to each other,” Rieser said. “It was not intolerably hot; the smoke was what was hard. We called in an air tanker and heard it make the drop about half a mile away; that was scary because we realized the smoke was so thick they didn’t even know where we were. It was an out-of-control situation, and our fate was in the hands of people who had made very questionable decisions. That was the turning point for me. I’ve been on worse fires, but I always pull the crews out before it gets bad. They say, ‘Aw, we could’ve held that,’ and then they watch it boil over.”
In 1871 a forest fire swept over the town of Peshtigo, Wisconsin, and killed more than fifteen hundred people. A fire in Chicago killed another three hundred people on the same day and is known as the Great Chicago Fire; the Peshtigo tragedy isn’t known as anything. Fires come in waves or complexes, and the Peshtigo and Chicago tragedies were part of a wide swath of fires that year that extended from Ohio to the High Plains. Since 1900 well over seven hundred people—it’s not known exactly how many—have died on wildfires in America, the vast majority of them men who were employed or had volunteered to fight the fires. The mass tragedies are mostly from the early days when there were no radios, no fire shelters, no aircraft, and no accurate weather forecasts. The next big fire complex after Peshtigo was the Big Blowup of 1910. Eighty-five men died battling the fires, some of them because they panicked and committed suicide after the fire lines were overrun. State troopers played taps over the caskets and buried them in mass graves in the hills. It was just this side of war.
In the end five million acres were burned in 1910, and flame-killed trees provided fuel for reburn cycles that lasted well into the 1930s. Reburns spread into healthy timber and ultimately redoubled the acreage that was lost. Faced with the possibility of a lumber shortage and consequently under tremendous political pressure, the Forest Service finally gave fire suppression top priority. Money was appropriated by Congress, crews were organized, lookout towers were built, timber companies constructed access roads into the mountains, telephones began to replace runners and mounted messengers. Fire fighting had finally entered, as one historian said, its heroic age.
The new approach showed results, but the West was still vulnerable to large-scale conflagration. The next big round of tactical changes came, not surprisingly, after the next big catastrophe, the Tillamook burn in 1933 that laid waste to half a billion board feet of Douglas fir in Oregon. Like the Big Blowup, Tillamook was merely the flagship of an armada of fires—Matilija, Selway, and others—that pummeled the West for three years. They prompted the Forest Service to adopt its famous 10:00 A.M. control policy, which meant that all fires were to be brought under control, if possible, by 10:00 the next morning. The policy would have been complete hubris were it not for a growing arsenal of fire-fighting tools: bulldozers that did the work of fifty men; airplanes that dropped thousands of gallons of retardant at a time; smoke jumpers who hit remote fires that would have taken men days to reach by foot. The idea was to get into the mountains fast and control the fires while they were still small; if a fire got away from the initial attack crews, thousands of lesser-trained men could be brought in to take over. As a tactic it made sense; as a public relations ploy it was unparalleled. Funding from Washington became effectively unlimited and remains so to this day.
As weather forecasting and communications improved,
the loss of life declined, but mass tragedies still occurred. In 1937 a Civilian Conservation Corps crew of fourteen on the Blackwater fire were trapped between a spot fire and the main fire; they decided to turn and fight the spot rather than run, and they all died. In 1943 eleven marines died and seventy-two were injured when Santa Ana winds changed abruptly on the Hauser Creek fire in Southern California. In 1949 thirteen smoke jumpers and another man died in knee-high grass during a blowup on the Mann Gulch fire in Montana. In 1956 eleven convicts died on the Inaja fire in Southern California, and ten years later a hotshot crew lost twelve men in nearly identical circumstances on the Loop fire in the Angeles National Forest. A spot fire started at the bottom of a canyon, blew up unexpectedly, and ran twenty-two hundred feet of the canyon in less than a minute. That’s twenty-five miles an hour. The crew didn’t have a chance.
By the 1970s fire crews had portable fire shelters and Nomex clothing and could theoretically survive some burnovers. Fire shelters start to disintegrate at around six hundred degrees, though, and a fire run in heavy timber can hit temperatures three times that high. The only thing that will save a crew in the face of such an inferno is to get out of the way before it hits, and to that end researchers at the Intermountain Fire Science Laboratory in Missoula, Montana, have developed mathematical models that predict—given certain fuel conditions, terrain type, and meteorological conditions—what a fire will do. These models have been programmed into computers and can be used in conjunction with satellite data to project fire growth on any fire anywhere in the United States. The incident command team on a fire can punch its location into a computer, along with topographical and meteorological information, and receive very specific information about likely fire behavior the following day: which canyons will burn out; which ridgelines will hold.
Still, no amount of computing power can predict exactly what a fire will do.
“Nothing we’re doing today is more important than a human life,” one incident commander said at a 6:00 A.M. briefing.
That sentence—more than fire behavior models, lightweight fire shelters, or advanced meteorology—explains why people no longer die in the terrible numbers they used to on wildfires in the United States.
In the middle of the afternoon we moved down off the ridgetops toward H-6. Helicopters were to lift us and the three crews down to the fire camp for the night. I was in no hurry to leave the mountains, but the Union, Negrito, and Smokey Bear crews were being replaced by type two outfits that hadn’t spent the last two nights spiked out. We clustered around the helispot and then piled onto the helicopters with our line packs and were shuttled back to camp.
That night I heard that a fire had just leaped the huge Salmon River Canyon up by McCall; a fire had started north of the river and a backburn had been set by dropping flaming Ping-Pong balls from a helicopter. (The Ping-Pong balls are filled with potassium permanganate and ignited by antifreeze. A needle injects the antifreeze at the moment of release and they ignite after thirty seconds, usually after they hit the ground. The helicopter pilot had circled to check his work, and one of the balls had accidentally released over the south side of the river. That was all it took. Within hours the new fire was fifty acres in size and crowning through heavy timber.
I drove up to McCall the next morning to see if I could get on the fire, but by then it was so far out of control that no one was allowed near it. Crews were cutting indirect line miles ahead of the fire and cold-trailing their way southward from the river, but that was it. The town of Riggins was filled with smoke; there was a mushroom cloud of smoke pumping out of the canyon; the airfield at McCall was crammed with reserve helicopters. But I wanted to see real flame. I slept on a sandbar along the North Folk of the Salmon River and drove back to Boise the next day. There was another fire north of town, I was told. It was racing through the dead-brown hills, and hotshots were getting pulled off Foothills to deal with it. It was bad, and it was moving fast.
There’s a little river that runs through Boise, and from the cafés that line the river walk, I could look up and watch the mountains burn. A big head of smoke was pumping out of the hills to the north, and retardant-streaked air tankers were making nonstop runs to and from the tanker base at the Boise airport, south of town. According to dispatch, bulldozers were trying to save a subdivision off Highway 21, wind-driven flames were racing through the terrifically dry sagebrush and cheatgrass around Lucky Peak Reservoir, and fifty crews left over from the Foothills fire were waiting to go in. I picked up a pass for the roadblock and headed north up Highway 21, toward the smoke.
Manpower was so short that the roadblock was guarded by a middle-aged couple in lawn chairs. I showed them my letter, and they waved me through. Soon I was alone on the dirt road that led into the burn zone. A line of flame hung like a necklace along the parched flanks of the hills. Smoke had turned the sunset blood-red. After three or four miles there was a hand-written cardboard sign that read: AREA CLEARED @ 19:30 HOURS 9/2—U.S.F.S. Just beyond that was the fire. It had reached the road and was swirling around a utility line that continued on up into the hills. I stopped the car and got out, completely alone with the fire and the mountains and the huge dead sky. Ten-foot tongues of flame licked the guardrails and shot into the sky. The vegetation died loudly, as if in pain, popping and exploding in the thickening dusk.
I took a few photographs and then went back to my car. The fire was about to jump the road. It would eventually move up into some timber and end up torching over thirteen thousand acres. A house would burn down. The beautiful Leonard ranch would be saved—barely—by ground and dozer crews backed up by massive air attack. It was called the Dunnigan Creek fire. It was one of roughly one hundred thousand wildfires during the summer of 1992, and if you ask a hotshot if he’s ever heard of it, chances are he’ll say no. Rain put it out after a couple of days.
Author’s Note
This essay was written in 1992, and since then there have been many changes in the way wildfire is fought in the United States. I wanted to alter the original work as little as possible, so it should be noted that—among other changes—the Boise Interagency Fire Center is now called the National Interagency Fire Center; fire fighters are paid more than $8.50 an hour; and portable computers are in common use for predicting fire behavior.
Most significant, however, the fatality statistics have changed. When I was in Idaho, it had been twenty-six years since more than half a crew had died in a single incident—the Loop fire in southern California, where twelve hotshots were overrun in a matter of minutes. Tragically, in 1994, fourteen hotshots and smoke jumpers were overrun in similar circumstances on the South Canyon fire outside Glenwood Springs, Colorado. The South Canyon fire is now the deadliest fire since 1937. My account of that incident appears as “Blowup,” the second essay in this collection.
Many hotshots I spoke with attributed the increasing danger of their job to severe drought conditions in the northern Rockies, as well as to decades of rigorous fire suppression. Both have contributed to a huge buildup of dead fuel in our nation’s forests—fuel that ordinarily would have been cleared out by the small fires that regularly flare up in an unmanaged ecosystem. A disastrous fire season was inevitable, and in 2000 it finally happened. Eighty-five thousand wildfires burned nearly seven million acres across the United States. Sixteen people died, and fire suppression cost over one billion dollars.
It was the worst season ever. With the western drought continuing unabated and huge amounts of deadwood still choking many forests, fire behavior experts don’t expect conditions to get better anytime soon.
BLOWUP: WHAT WENT WRONG AT STORM KING MOUNTAIN
1994
The main thing Brad Haugh remembers about his escape was the thunderous sound of his own heart. It was beating two hundred times a minute, and by the time he and the two smoke jumpers running with him had crested a steep ridge in Colorado, everyone behind them was dead.
Their coworkers on the slope at their backs had been o
verrun by flames that Haugh guessed were three hundred feet high. The fire raced a quarter mile up the mountain in about two minutes, hitting speeds of eighteen miles an hour. Tools dropped in its path were completely incinerated. Temperatures reached two thousand degrees—hot enough to melt gold or fire clay.
“The fire blew up behind a little ridge below me,” Haugh said later. “People were yelling into their radios, ‘Run! Run! Run!’ I was roughly one hundred and fifty feet from the top of the hill, and the fire got there in ten or twelve seconds. I made it over the top and just tumbled and rolled down the other side, and when I turned around, there was just this incredible wall of flame.”
Haugh was one of forty-nine firefighters caught in a wildfire that stunned the nation with its swiftness and its fury. Fourteen elite fire fighters perished on a spine of Storm King Mountain, seven miles west of Glenwood Springs, Colorado. They died on a steep, rocky slope in a fire initially so small that the crews had not taken it seriously. They died while cars passed within sight on the interstate below and people in the valley aimed their camcorders at the fire from garage roofs.