A hot spot from the Lower East Adams Lake wildfire burns in Scotch Creek, B.C., on Aug. 20, 2023.DARRYL DYCK/The Canadian Press
Along the snowbanks flanking the highways and main roads in and out of towns in British Columbia’s northeast, plumes of smoke rise out of the ground.
Sonja Leverkus, a wildland firefighter crew leader who lives in Fort Nelson, B.C., said the smoke emanating from underground fires left over from last summer’s unprecedented wildfire season sometimes pushes out of the ground with such force it looks like a geyser.
Residents near the community about 200 kilometres south of the B.C.-Yukon border say the air can get thick with smoke, making it difficult to breathe.
“A lot of people have talked about the 2023 fire season being over, but it’s not over. It is not over in northeast British Columbia,” said Ms. Leverkus, who is also a prescribed fire specialist and an adjunct professor at the University of Alberta’s wildfire analytics lab.
“Our fires did not stop burning.”
As of this month, the BC Wildfire Service (BCWS) map shows there are some 105 wildfires continuing to burn in British Columbia. Some of them are likely out and BCWS hasn’t been able to confirm, but others have continued to smoulder underground, threatening to kick off another bad wildfire season in 2024 as the province experiences severe drought.
On Jan. 1, 2023, B.C. recorded 16 “carryover” fires, and BCWS statistics show most years since 2014 recorded five or less. Alberta Wildfire reports similar numbers. According to a spokesperson for the service, Alberta’s five-year average for carryover fires is six. The province currently has 60 active fires.
Jennifer Baltzer, a professor and Canada Research Chair in forests and global change at Wilfrid Laurier University, said the drought leading up to last summer, the 2023 fire season’s hot and dry conditions and sustained lightning activity, as well as the increased number of fires across the landscape in general, are all factors behind why B.C. is seeing more frequent overwintering fires.
British Columbia saw more than 2,250 wildfires last year, according to BCWS statistics, and wildfires burned over two million hectares of land.
“When you have those kinds of conditions, the soils and plant materials are drier, there’s more fuel, and there’s greater potential for that to smoulder,” Prof. Baltzer said.
Under normal conditions, experts say carryover fires aren’t a cause for concern – almost all of the 105 active fires are in the BCWS “under control” category, meaning they are not at risk of spreading any farther. Experts say this is largely because they’re smouldering inside already burned landscapes with few leftover fuels, so there’s a low risk of reignition. Many of these hotspots will also be naturally extinguished by snow and rainfall in the coming months.
Sometimes, though, these fires can survive for months throughout the winter, smouldering multiple metres underground in deep layers of peat, muskeg, moss and other organic material.
Any hotspots that survive the winter snow and rain to wake back up in the spring again officially earn the title of “zombie fire.”
“The big concern is that these overwinter fires will reignite and spread into places that didn’t burn last season,” Prof. Baltzer said. “If you’ve got this smouldering fire at the edge of a perimeter of a fire from 2023, if that reignites, it has the potential of actually spreading across the landscape into unburned forests.”
As of December, 2023, Agriculture and Agri-Food Canada reported that 88 per cent of B.C. was in “moderate to extreme drought” conditions. The province is currently seeing temperatures more than five degrees above normal and below-average precipitation levels. Some areas in the Peace River region in northeastern B.C. received amounts of precipitation between 40 per cent to 85 per cent lower than normal, according to the update.
Earlier fire seasons extend the impact fires can have on people who live in remote towns, where wildfires are more likely to occur nearby. Longer seasons mean the risk of a fire encroaching on a community exists for a longer period of time, which can take a significant toll on local residents’ physical health and mental well-being.
“For the first time in my entire life, I experienced that term ‘worried sick’ and it happened constantly during the last summer,” Ms. Leverkus said.
Many of the fires she fought in 2023 continue to burn around Fort Nelson today, despite consistent snowfall and local temperatures ranging from -25 to -40 C. More than 80 of the 105 fires still considered active by the BCWS are burning in the Prince George Fire Centre, where Fort Nelson is situated. This is mainly because overwintering fires typically burn in peat, a soil type common to northeastern B.C.
Ms. Leverkus also worries about “danger trees” – trees at risk of falling because their root systems have been compromised by fire and drought – and people stepping into ash hotspots, which are so warm they could quickly burn skin, even in snow and winter temperatures significantly below zero.
Since zombie fires are and look so foreign, winter bush workers and people out for sports and recreation might not be able to recognize the dangers signs of a landscape that’s still on fire, she said, describing the conditions as akin to “walking in a minefield.”
“With those ignition sources with that wind, it’s highly possible that if we don’t get precipitation in the beginning of April, we’re going to start seeing some fire activity.”
Forrest Tower, a communication and engagement specialist at the BCWS, said the service does expect some carryover fires to reignite in the spring, but the number will be determined by how much snow and precipitation the province sees over the winter.
They are not a huge concern to the service at this time, he added, saying that the BCWS watches the fires over the winter.
“Those that still remain in the spring, we deal with as soon as we’re able to, once we have our firefighting staff back and conditions make it possible to get to where these fires are.”