Researcher recommends caution with potential Dawson City land development due to possible flood risk

A senior researcher at Yukon University says the Tr'ondëk Hwëch'in First Nation and the Yukon Government will need to be careful in planning development on neighbouring parcels of land in Dawson City because the area has been known to flood in the past. 

Benoit Turcotte, who focuses on hydrology and climate change, said the area is not a naturally occurring flood plain, but it has been modified in past decades by mining activity on the Klondike River.

“Now we see rock piles, we see ponds, and it's not exactly your typical flood plain,” he said. "I would say it would be safe to build there if the elevation is correct but if we also maybe leave space to the river."

Tr'ondëk Hwëch'in First Nation and the Yukon Government signed a memorandum of understanding for a joint master planning process for the land next to the Dredge Pond subdivision.

Turcotte said developers should be mindful of the increasingly high snowpacks in the Klondike Valley, which can contribute to flood risk. Even in dry years, he said, there’s more water in the Klondike River.

“We should expect snowmelt flows in the order of 1,000 cubic metres per second in the future, which is higher than what we've seen. And we will continue to see ice jams in that river.”

One way to decrease water levels, said Turcotte, is to try and work with the Klondike River, rather than against it – by giving it natural channels. 

That could involve creating a flood plain for the river by taking away the top piled rocks left over from mining activities and planting some terraced vegetation, he said. That way there is a space for the river to wander and to reduce the intensity of its flow rather than racing through an empty area with nothing to slow it down. 

"I would say nature wishes that there was more space without any properties so that it could flood,” Turcott said.  “And that's a way for the river to actually just dissipate its energy."

Upstream of the Dawson airport, Turcotte said, the Klondike River has a flood plain, “with forests, with small channels, with little beavers and all that. And when you reach the tailings, the river has been pushed on the wall of the valley, and it's been kind of constricted.”

“So it cannot really dissipate its energy as a natural channel. So when a river cannot dissipate its energy, it means that it carries a potential to provoke erosion, including massive erosion.”

Cory Bellmore, the minister of community development, said the two governments are in the early planning stages. 

Talks involve figuring out what they can do with the land and if there are any problems with it, including potential flooding. 

“We don't know at this point what type of lot development it'll be. That all comes as part of the master planning process,” she said.