The Press in Yukon | A natural barrier to protect Whitehorse

The wildfire season is raging and, like many cities, Whitehorse, Yukon, is not immune to the flames. To protect itself, authorities began building a permanent firebreak some 20 kilometres south of the municipality a few years ago, one of the most extensive barriers of its kind in the country. The Press visited the site and spoke with Luc Bibeau, head of the Yukon Forest Fire Management Section’s Prevention and Mitigation Unit.

(Whitehorse, Yukon) You say the firewall you are building is different from the “old way” of doing things. Why?

A lot of firebreaks have been built with bulldozers, sometimes in a hurry. Trenches are dug down to the mineral soil so that nothing can burn. This is very effective in the short term. But in the long term, it causes the return of invasive species and does not fully maintain the ecosystem of a forest.

In our case, we do not remove the organic layer. We integrate different management techniques that involve removing forest fuels, fragmenting them, isolating them or converting the area.

How it works ?

We remove trees to thin the forest. Air tankers are much more effective when dropping retardant or water into thin forest cover.

And when we talk about converting, we’re talking about removing fuels like spruce trees or debris, and doing prescribed burning. Then we plant aspen trees.

Our goal is to get the fire down from the treetops to the ground. So we’re trying to reduce the intensity of the fire and how quickly it spreads.

What’s new is that we’re building permanent, strategic infrastructure on a large scale, with conversion techniques that involve native species, and that we want to maintain for as long as there are people living in Whitehorse.

You are planting a huge swath of aspen trees to protect the city. Why this species in particular?

This is a native species that grows naturally in the Yukon and is fire resistant. These trees retain moisture, so they don’t burn well. It is also a resilient species: the tree can produce a sucker once it is well established in the ground. If it were to burn, others would grow in the area.

This is a long-term approach, which transforms a high-risk forest dominated by conifers into a low-risk area with deciduous species.

Are natural barriers limited when it comes to countering a particularly aggressive fire?

They are not a silver bullet and, in the most extreme weather conditions, they may be ineffective. Firebreaks are useful because they are containment lines that help firefighters contain fires.

But managing forest fuels must be accompanied by reducing risks to structures, homes and neighborhoods. Creating more fire-resilient communities will require a whole-of-society effort.

Is it expensive to build a firewall of this magnitude?

When you compare it to the potential loss, the return on investment is incredible. It’s very cheap compared to the billion dollars in losses that would result from destroying a large neighbourhood in Whitehorse.

The cost of our firebreak is about $12 million. That’s not much compared to other infrastructure like a bridge or flood protection facilities. The long-term maintenance will be very, very inexpensive.

In the past, one of the challenges has been having the financial resources and enough people to do the work. And that’s changing. There’s a lot more political will and support from the territorial government and the federal government to reduce the risk associated with wildfires.

Whitehorse residents have publicly voiced their reservations about the firebreak. Is social acceptability an issue?

Another big challenge for a very long time is indeed social acceptability. Ten years ago, I don’t think this type of project would have been possible. But public attitudes have really changed because of the very difficult wildfire seasons of the last few years.

Part of the reluctance comes from a misunderstanding of the risk, because people don’t always see the fires we quickly put out close to the city. Also, Yukoners have a strong attachment to the forest. They ride their bikes, walk their dogs, cross-country ski. They would like to see it stay the same, and they don’t like the idea of ​​not using or seeing these spaces in the same way because they’ve been changed.