Beaver dam collapse believed cause of Alaska Highway washout

Beavers behind hwy chaos

Engineers are on their way to a major washout along a remote section of the Alaska Highway in Northern B.C. to assess damages and determine a fix, officials say.

The washout destroyed a massive section of paved highway about 125 kilometres north of Liard Hot Springs on July 1, snarling long weekend traffic travelling in both directions, and prompting some stores in the Yukon to ration goods.

George Smith, manager of maintenance for the portion of the Alaska Highway under federal jurisdiction, says engineers flew into Fort St. John and are driving north today. They’ll be flown to the site tomorrow to assess what happened and what the options are to restore the road.

“The pictures don’t do it justice,” Smith said Tuesday of the scale of damage.

It’s believed the washout was caused by a beaver dam collapse, which brought with it a torrent of water from a nearby lake that washed out the highway.

On Canada Day, the traffic monitoring service DriveBC had reported water pooling  between the Fireside Maintenance Camp and Allen’s Lookout. Just hours later, however, the road gave way, destroying a large section of paved highway.

“The beaver dam let go, the lake more or less drained, and took the highway out,” Smith said.

Traffic on the both sides of the large crevasse have been kept back due to the instability of the nearby hillside and the potential for more erosion.

A three-kilometre detour has since been opened using an old alignment of the highway. Smith says crews had to put in a culvert, fix approaches to the highway, and “do some dirt work” before it could be opened. 

He says the detour is being maintained and monitored daily with the help of Lower Post First Nations, and open 24 hours to single-lane alternating traffic with a pilot car.

The “road is good” and there are “no restrictions as of yet,” Smith said, noting transport trucks and motor homes are being piloted through. He asked motorists to be patient and obey the signs.

“It’s taken the pilot car nine to 10 minutes to get traffic through there,” he said. “We can’t stress enough that they obey signs and wait for the pilot car.”


More BC News