Snowy winter in Yukon has experts eyeing flood risk

It was a snowy winter in many parts of Yukon — just ask Norma Mease in Mayo.

“It started in the middle of October and it never quit until probably this month,” she said on Tuesday. “We haven’t had any rain or snow lately, but it looks like it could snow.”

Mease says things have been melting slowly around Mayo, and hydrologists hope that continues. With so much snow everywhere, a rapid melt could cause problems.

Benoit Turcotte, a Yukon government hydrologist, says so far there’s no major cause for concern, but he’s keeping an eye on the weather forecast.

“We hope that we won’t get very warm temperatures too soon, so that snow melts gradually and avoids any flooding,” he said.

Every spring, the government routinely measures the snow in different regions of the territory to assess the risk of flooding month-by-month.  According to the government’s monthly bulletin for April, many regions still had a “snow water equivalent,” or accumulated snowpack, higher than the historical median.

For example, the Pelly River basin in central Yukon on April 1 had the highest recorded snowpack since 1980 for this time of year.

“The record high snowpack in the watershed increases the probability of significant May and June peak flows, including rivers and streams crossing the Robert Campbell Highway and Canol Road. A sudden rise in air temperatures in April or early May could also be conducive to ice jamming,” the report reads.

Higher risk than usual in southeast Yukon

The Liard River basin in southeastern Yukon also has a lot more snow than usual, Turcotte said. 

“Right now the Liard and the north part of the basin, there’s still a lot of concerns because there’s still a lot of snow. So I would say right now the flood potential in Upper Liard/Lower Post is slightly higher than usual because of that,” he said.

“So it’s still on my list of communities to have special attention to.”

‘Snow water equivalent’ measurements on April 1. The darker blue areas indicate regions where the snowpack was significantly higher than the historical median. (Yukon Department of Environment)

He’s also keeping an eye on the rising Klondike River, where ice jams have caused problems in years past

“There’s no breakup yet, there’s no ice movement yet, and the ice cover’s still thick. And hopefully, again, we’ll have some cooler weather for at least a week in order for the first wave of water to be evacuated from that system,” he said.

“Right now, those water levels are probably stable, as we speak.”

The snowpack in the Whitehorse and Southern Lakes region is also a little higher than usual for this month, but Turcotte says there’s a low risk of flooding.

“The upper lakes will absorb a lot of water this spring, and right now the snowpack from my point of view is not critical. This year is following a very dry year,” he said.

Hydrologists will take more snow measurements next month. In the meantime, Turcotte is keeping tabs on the forecast.

“For now, my job is to really look as far ahead as the weather forecasts allow, and for now I don’t see anything of concern in terms of warm temperatures or rain.”

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