Annual Spring Clearing Begins On 3 Washington Mountain Passes

Three routes over the mountains are getting closer to reopening for the season as state transportation crews get to work clearing out the snow from the North Cascades Highway and Cayuse and Chinook Passes.

SR 20, SR 123 and SR 410 close every year due to heavy snow and avalanche dangers over the winter months. Their reopenings serve as one of the most reliable signals of warmer days to come.

The North Cascades Highway closed last November, as the roadway between the Methow and Skagit valleys sits right in the path of dozens of avalanche chutes. According to the Washington State Department of Transportation, last winter's snow levels were a bit higher than usual and the Liberty Bell chutes are still holding significant snow. The added hazard made it necessary for crews to allow some extra time for more snow to melt.

For SR 20, reopening work begins Monday, April 5, and typically takes between 4 and 6 weeks to complete. During that time, crews use bulldozers and blowers to clear several feet of snow off the highway while watching out for persisting avalanche dangers, rocks, trees and other debris. Once the roadway is finally clear, guardrails also require repairs.

According to WSDOT, hikers, skiers and snowmobilers will still be welcome to use the highway between Friday and Sunday.

Work to clear the Chinook and Cayuse Passes, the two scenic routes that run through Mountain Ranier National Park, began earlier in March. Both passes closed for the season on Nov. 12, 2020. Chinook Pass, on State Route 410, remains closed between Crystal Mountain Boulevard and Morse Creek. Cayuse Pass, SR 123, is closed from Crystal Mountain Boulevard and the southern park boundary.

Each year on average, maintenance crews must clear over 30 miles on both passes, using bulldozers and blowers to carve through snow more than 30 feet deep in some areas. The goal is to reopen both roadways before the Memorial Day weekend in late May. Last year, they opened on June 4.

Learn more about how crews clear the mountain passes each year on the WSDOT website.