Fires could continue burning underground over winter: province

Eric Reder, Wilderness Committee campaigner, breaks down zombie fires, caribou impacts, and why hotter forests demand stronger fire response.

In the wake of a historic wildfire season, the province warns fires could continue burning underground throughout the winter and flare up in the spring.

Over the summer months, 2.1 million hectares burned across the province in what became the worst wildfire season Manitoba has faced in three decades.

According to the province’s daily fire situation report, there are still 66 fires burning in the province, most in northern areas.

None are considered out of control.

“The Manitoba Wildfire Service is monitoring all remaining fires, and a decent snowfall should extinguish many of them,” a spokesperson said in an email.

The spokesperson noted mild temperatures and limited precipitation will have slowed the natural extinguishing process. They said it’s possible some of these fires may ‘overwinter,’ burning deep underground where rain and snow have less of an impact.

“These fires smolder, burning slowly with little oxygen, so big flames are not produced.”

The spokesperson said the Manitoba Wildfire Service carefully monitors winter conditions and keeps tabs on what areas may be at a higher risk in the spring.

“This helps the province to prepare to respond quickly if fires re-emerge in the spring, flying over those areas to monitor for any early activity,” they said.

Eric Reder with Wilderness Committee, a non-profit nature and wildlife advocacy group, said fires still burning underground are nicknamed ‘zombie fires,’ as they move into the soil and keep smouldering, and moisture cannot reach them.

One of the reasons the fires can still burn underground in Manitoba is due to the presence of peat bogs, he added.

“There’s so much carbon in peat, the decomposing sphagnum moss, that once it burns, it doesn’t even need very much oxygen,” he said during an interview Wednesday with CTV Your Morning Winnipeg.

“So it’ll be below the soil, and it’ll be burning, but just it’s the most carbon rich terrestrial area on the planet, and so once they start burning, unless you get significant moisture, it’s not going to go out.”

According to Reder, this year’s wildfires burned an estimated eight per cent of the province’s forests.

“That should really alarm us,” he said.

- With files from CTV’s Rachel Lagacé