Peel River driftwood raises questions for some in Fort McPherson

As the ice started to move down the Peel River earlier this week, Fort McPherson, N.W.T., elder Robert Alexie Sr. noticed something slightly unusual.

There was more driftwood than normal.

"There's a big pile of driftwood coming down piles of it," said Alexie. "You gotta go up ... the Peel to find out. Find if it is jammed or something like that?"

On Monday, Alexie said the water in the river close to Fort McPherson was very low, but had started to rise. Posts on Facebook showed the river was starting to flow steadily on Tuesday, with big chunks of driftwood flowing with the ice.

Steve Kokelj, a permafrost scientist with the Northwest Territories Geological Survey, who has been studying permafrost in the region for more than 20 years, said that landslides could be a factor.

Landslides have become more common in the Beaufort Delta region, Kokelj said, butthey usually happen in the summer and fall.

Watch Marlene Snowshoe's video of the Peel River breakup:

Driftwood on the Peel River, N.W.T.

4 years ago

Duration 1:09

Driftwood floats down the Peel River during spring breakup.

Landslides getting bigger

"We know that the landslides are getting bigger and bigger and in some areas they are moving forests from the slopes into the valleys," he said. "But because those happen in the summer, when the water levels low, those trees don't get moved by the river.

"They are only going to get moved when you have either a really big rainfall event or snow melt, which brings the water level up and allows the river to move all that material."

He said he's noticed an increase in landslides in the Peel Basin.

"Landslides that are driven by permafrost thaw have increased ten to a hundred fold in different drainages that flow into the Peel," said Kokelj. "There's more intense summer rains, so you kind of get this bank erosion and that wood just stays there and it doesn't really move until the spring."

Kokelj said he's heard that people have been noticing more driftwood in recentyears, but the reason the wood is in the river may not be directly related to the spring freshet.

Kokelj said there hasn't been as much research into this on the Peel River.

"It's a connection that I think researchers have made in different places, but I don't think it's really been looked at in detail in the Peel [River]"

Kokelj said wood is sometimes in the river for a couple of years, but stored in the floodplain.

Driftwood common during break-up

Kokeljsaid there aremore landslides in other areas as well.

In 2017, Kokelj said there were between 80 and 100 landslides along the Mackenzie River near Reindeer Station.

Joslyn Oosenbrug, a spokesperson for Environment and Natural Resources, said in an email that the department isn't sure why people are noticing an increase in driftwood, however driftwood is common during break-up.

Oosenbrug also wrote that as the ice melts, the driftwood appears to "concentrate" in the river.

She also wrote a contributing factor to build-up driftwood in the Peel River could be more snow than average this winter on the Yukon side, along with forest fires in the river basin which could have resulted in more driftwood during the spring freshet.