A significant portion of the Denali Park Road closed Tuesday for the rest of the season as a landslide caused unsafe driving conditions, the National Park Service said in a statement.
The 92-mile Denali Park Road is the only way to drive into the 4.7-million-acre park. The continuing landslide at Polychrome Pass, near Mile 42, has led to the road rapidly deteriorating in recent years, causing concern about how to maintain the road while safely accommodating visitors.
“Changing climate is driving frozen ground to thaw, resulting in unpredictable and increasing landslide movement rates at Pretty Rocks that are unprecedented in the history of the park road. We cannot safely keep up with the accelerating rate of landslide movement caused by permafrost thaw currently occurring in association with the Pretty Rocks Landslide,” Don Striker, Denali’s Superintendent, said in the statement.
The Denali Park Road normally closes past the Teklanika Rest Area at Mile 30 in mid-September.
After Tuesday, westbound traffic beyond Mile 43 will only be allowed for essential purposes, like facilitating seasonal closure of western park operations, the park service said.
The closure will impact the Wonder Lake Campground near Mile 89 and the Eielson Visitor Center at Mile 66, the park service said.
About 84 people who are camping or accessing the backcountry west of the closure on Tuesday will be relocated in the coming days, said park spokesman Paul Ollig. People at Wonder Lake Campground are being relocated by park transit buses Tuesday and Wednesday and backcountry users will be picked up by park camper buses when they return to the road during the next few days, he said.
The visitors are not stranded, Ollig said.
“Some visitors are being relocated to campgrounds east of Polychrome, where space is available, and others are simply choosing to shorten their trips,” he said by email.
The park service said camper buses won’t be able to accommodate backcountry trips past Mile 42, effective immediately. Park tour and transit buses will continue making trips, but they will stop and turn around at Mile 42.
The Denali Visitor Center, front-country trails and backcountry access remain open, along with the Kantishna airstrip, which is located near the end of the road.
The Pretty Rocks Landslide is located around Mile 45 of the highway has required increasing maintenance in recent years because it is changing rapidly due to climate change, the park service said.
In 2018, the landslide was causing the roadway to slump almost half an inch per day and by August of last year it had increased to 3.5 inches per day, the park service said.
“Early August rains in 2021 appear to have triggered the rate to increase significantly, with much of the landslide currently moving downhill at over ten inches per day,” the statement said.
The park service’s 2022 budget request includes funding for a construction project at Polychrome Pass to maintain access, the statement said. The project is in the planning and design stages and the park service said construction would not begin until at least 2023.