MAZAMA – A snowy forecast means Highway 20, the North Cascades Highway, will close for the season at 6 a.m. Wednesday, Dec. 11.
It is the latest seasonal closure date in more than a decade.
Washington State Department of Transportation crews close the stretch every year once snow fills avalanche chutes that line the highway. They pose a risk to crews and the public.
Closure points are at milepost 134, the Ross Dam Trailhead, and milepost 171, Silver Star Gate west of Mazama. When significant snow begins to fall, crews will move the western closure point back to milepost 130, Colonial Creek Campground, and the eastern closure point to milepost 177, Early Winters Campground.
The weather-dependent changes usually happen in January. Signs along Highway 20 are posted in advance of the closure point and updates on the state Department of Transportation website will reflect where the road is closed.
Hikers, skiers, snowmobilers and other recreationalists can access the closed portion of highway during winter. Users should park in designated parking areas to allow plow drivers the space they need to clear snow around the closed stretch’s access gates, the agency said.
Since the highway is closed because of avalanche risk, people using the area are advised to check forecasts and be aware of quickly changing conditions in the mountains. Travelers can also check conditions with North Cascades National Park before trips to this area.
The highway has remained open only one winter, 1976-77, since its opening in September 1972.