A massive avalanche closed US 2 at Stevens Pass on Wednesday for about seven hours.
The Washington State Department of Transportation said there was about five feet of snow sitting on four lanes of the highway from milepost 54 near Scenic to just west of the summit.
“The snow that’s been coming in from the past couple of weeks turned to rain. When that rain hit the layer of snow that was on the mountain snow, we got a natural avalanche on Old Faithful #4,” explained WSDOT spokesperson Jeff Adamson.
Adamson said they used plow trucks, snow blowers, a couple road graders, and a snowcat to clear the road.
“When an avalanche chute comes down on its own, typically it’ll come in a couple of times. The first layer will come off and then the second layer is exposed and it’ll come down a short while later,” said Adamson. “So in this case, there are about a dozen chutes in that area that are probably in the process of destabilizing.”
While it sounds dangerous for road crews, Adamson said they have plenty of experience clearing slides and avalanches.
The Stevens Pass area received about 150 inches of new snow in the last two weeks, according to Adamson. The avalanche crew has used about 3,500 pounds of explosive this year to help keep the highway clear. Crews regularly use trams and surplus military tanks to fire shells into the top of twelve avalanche paths.
Typical traffic volumes over Stevens Pass is about 4,500 vehicles and about 450 of those vehicles are freight, according to the WSDOT.
Stevens Pass ski area posted an awe-inspiring video of their own avalanche control efforts on YouTube: