VALEMOUNT, B.C. -- An avalanche has triggered a large landslide, which has blocked Highway 16 near Mount Robson, on the Alberta-B.C. boundary, RCMP say.
Const. Lesley Smith said the 40-metre-wide slide came down over the route at about 9:30 Monday morning.
"At this stage, it's unknown if any vehicles were involved or caught in the avalanche."
Smith said the Transportation Ministry is warning that the risk of additional slides is very high and that it's too dangerous to enter the area to look for any vehicles.
No detours are available to get around the slide.
Smith said an avalanche technician was on the way as officials with the Transportation Ministry assessed the slide.
Flagger crews are being placed at both ends of the slide, and in Tete Jaune, McBride, Valemount and Jasper, Alta.
Highway 1 is also closed indefinitely due to the avalanche danger.
Canadian Avalanche Centre forecaster Eirik Sharp said the most dangerous areas are currently parts of the south coast, the Sea-to-Sky region, the Coquihalla and the Columbia Mountains in the Interior.
While the danger of natural avalanches has subsided since the weekend, backcountry enthusiasts should be wary of the heightened risk of human-triggered slides, Eirik said from Revelstoke.
"People are going to be chomping at the bit. Riding conditions across the province haven't been very good until this point and on the surface now with this good load of snow things are looking really good."
However, weak layers of snow, from a snowfall early December have created a hidden danger for people enticed by fresh snow, Eirik said.
"Until we get more evidence that those layers are settling out and being less of a problem conservative decision-making is definitely going to be the best strategy for staying safe in the backcountry, and avoiding large open terrain," Eirk said.
"It's kind of like crossing a mine field right now. On a slope there's weak points where your likelihood to trigger an avalanche is increased.
"You could be lucky and you could run through the mine field and not touch one of them but if you were to step on one of those mines the consequences are going to be significant."
