Retreat and defeat in the boreal forest
An attempt to slow the growing wildfire with a controlled burn called for preparations to avoid letting the man-made flames reach the city. Crews worked hard, and on May 2 the mood was cautiously optimistic.
Smoke blanketed the scorched boreal forest on Monday morning, May 2, 2016. Under its cover slept Fire 9.
Through the previous evening, the wildfire had made its first push toward this northern city. The wet and cold of the night had at last halted the march of flames. In the respite, Fort McMurray fire bosses took to helicopters to try to get a sense of their adversary.
The veil of smoke stretched for hundreds of hectares west of the city. It confounded any precise measurement. Fort McMurray forest area manager Bernie Schmitte and his team estimated that the fire, blown by swift west winds, had on May 1 burned through 500 to 750 hectares of forest, taking on a cigar shape and aimed right at Gregoire, a suburb of more than 1,500 homes in south Fort McMurray.
That afternoon of May 2, the sun cooked the already parched boreal forest to 27 C, but good news came when the wind picked up. It reversed direction, blowing east-towest, taking the fire away from the city. Schmitte and his team of 20 firefighters and eight operators on two bulldozer crews had a window to try to contain Fire 9’s threatening finger pointing at the city.
Monday: Fire 9 ignites Today: The giant sleeps Wednesday: Fort McMurray burns Thursday: The battle for Birchwood Trails Friday: The fire rages south
When a wildfire burns hot and fast, no amount of retardant or water from air tankers will stop its progress.
The best bet against such a blaze is what wildfire experts refer to as burnout and backfire. Heli-torch specialists in helicopters rigged with torches spray flaming gasoline gel on a line of trees below to ignite a burnout. They attempt to torch a thin strip of the forest between the main body of the wildfire and a man-made or natural control line, such as a road or a river.
The controlled burn is to move toward the main inferno, either blown there by the day’s winds or by the great sucking in of oxygen by the primary fire itself. If the strip burns out thoroughly, it takes away the fuel that would otherwise keep the wildfire charging ahead. The hope is to slow the wildfire so the air tankers and ground crews can be more effective.
But Schmitte realized a backfire cannot be ignited on the edge of a city of 88,000 people. If the wind picked up and changed direction, the controlled burn could itself turn and threaten Fort McMurray. Schmitte needed protection, a line of defence through the forest that could stop a controlled burn if it moved in the wrong direction.
His heavy machinery crews went to work on a dozer guard, the idea being that bulldozers would take out a six-metre-wide swath and enclose the hot tip of Fire 9. Only then could they attempt a backfire.
The dozer crews had a tough test. Two small rivers, the Horse and the Hangingstone, wind their way through the forest west of Fort McMurray, creating deep valleys and twisting slopes.
No road or cutline existed to reach where the dozer guard was needed. Buried pipelines crossed the area. A shallow pipe might rupture under a bulldozer’s weight. The buried pipes had to be located, marked and covered over with swamp mats for safe crossing. And, of course, evacuation plans to ensure the safety of the men and machinery were a necessity.
For all that, by late afternoon the fire crews made progress. A few kilometres of dozer guard hugged the tip of Fire 9.
Twenty-eight firefighters, seven helicopters and two planes worked the northwest edge of the fire on May 2. Of the latter, one was a Convair 580 air tanker and one an Electra water bomber, with Ken Buchanan the pilot. In the city, some looked at the huge smoke column above the fire and worried, but it seemed to Buchanan, a 30-year veteran fighting wildfire, that things were going well. The fire was coming under control on its edge closest to the city.
At a late afternoon news conference that day, Schmitte was guarded but optimistic. The fire had doubled in size but was most active in its southwest corner, away from the city.
“We have some good news here,” he told reporters. “Our guys are feeling pretty good after today.”
To lead the firefight, Schmitte called in incident commander Doug Smith and the Provincial Type 1 team — Alberta’s best, most experienced specialists in fighting wildfire.
At its 5 p.m. meeting that same day in Fort McMurray, fire behaviour specialist Dave Schroeder gave the Type 1 team some troubling news.
The forecast for the coming day, Tuesday, May 3, wasn’t so bad: a hot day but with only light winds.
On Wednesday, May 4, or early on Thursday, May 5, however, Schroeder said a high pressure cold front was expected to blow in dry and gusty, with winds coming first from the southwest, then shifting to blow in hard and long from the northwest.
All the fire bosses knew what that meant. Such windy fronts often caused extreme and rapid change in fire behaviour.
Far north of Fort McMurray, Fire 9 reached the south bank of the Athabasca River just before sunset on May 2. As darkness set in, the blaze continued.
Sunrise on Tuesday, May 3, brought more bad news. From a helicopter, Schroeder saw that fire had spread dramatically overnight, far more than he had thought likely. It had again doubled in size. Worse, 15 km north of the city, fire embers had unexpectedly jumped 600 metres over the waters and shoreline of the Athabasca and started a handful of fires on the north bank. If those spot fires spread, they had a clear path to Fort McMurray’s northern suburbs, home to most of the population.
At 7 a.m., Schmitte called Fort McMurray fire chief Darby Allen with news of the fire jumping the river. At that moment, knowing the treacherous fire conditions, Allen started to mull the possibility of evacuating the city.
The fire slept under a shroud of dark smoke through Tuesday morning. In the city, no ominous columns of smoke could be seen over Fire 9 and there was little smoke polluting the air. It seemed like a beautiful, hot midsummer morning.
An inversion had settled over the fire. Cool air above held down the smoke. By late morning, however, the inversion broke. Warm air rose. The fire woke up. Multiple fire fronts ignited north and south of the Athabasca.
At Tuesday’s 11 a.m. fire update for reporters, Allen warned Fort McMurray residents not to get a false sense of security. The forecast high for the day was near 30 C, with 15 km/h winds expected from the southwest. “Fire conditions are extreme,” he said. “The fire is able to get into areas where we can’t stop it.”
Allen warned people to have a plan in mind in case they had to leave suddenly. “We’re a long ways off from that, but that’s something to bear in mind.”
The provincial fire bosses wanted to attack the north bank fires while they were still small. Kent Jennings, 30, led a heli-attack team dispatched to do the job. Like his twin brother Scott, he’d been fighting Alberta fires for more than a decade.
He scouted the blaze from a helicopter around 9 a.m. He was surprised the fire had been able to jump the river overnight.
This is going to be tougher than I thought, he thought. But maybe if the winds are favourable and we can get a dozer guard cut fast, we can get lucky and hold the blaze.
At the province’s warehouse at the Fort McMurray airport, Jennings gathered his team. But when they arrived in the late morning at the north bank fire, thick black smoke covered everything. There was no way to gauge the extent of the fire, let alone find a safe place to land.
The crew reluctantly returned to base. It was quickly reassigned to help on Fire 9’s threatening tip west of Gregoire, a neighbourhood on the city’s south end.
Jennings and his team were to set up bladders in the bush, large vats for collecting water, either by hoses from creeks or having helicopters bucket in water. The bladders would then feed the hoses of firefighters trying to douse hot spots.
Just as Jennings landed in the bush, winds picked up from the southwest and the temperature rose. The fire spread from the forest floor to the tree tops. But now instead of expanding on a narrow band at the tip, the wind rolled it over along its six-kilometre northwestern edge.
A massive wall of dark smoke and crown of flame charged toward Fort McMurray’s southwest suburbs, Abasand and Beacon Hill.
Embers flew high over Jennings and his crew and ignited spot fires over the dozer guard line. Each spruce tree that exploded into flame roared like a train. The forest soon howled like 500 steam engines.
Some new crew members grew fearful. Jennings could understand why. It did seem scary. And even though there were many people around him, as the team leader he felt suddenly alone. He was responsible for all, but not part of any group. What good could he do? He was immensely frustrated. He had wanted to dig in against Fire 9, but there was nowhere to make a stand.
Jennings could see looks of anxiety and doubt in the faces of his firefighters. Yes, most of them had seen fires get away before, but those fires were in the middle of nowhere. The stakes were so much higher here.
And now it was time to leave. Group after group, the firefighters were choppered to the safety of their airport base.
Firefighting could be enjoyable, Jennings had always thought. Tackling a new blaze, beating it back. But this constant retreat and defeat was not fun. This was devastating. He wondered if he would wake up from this bad dream.