Highway 20 over North Cascades expected to remain closed until July

The state Department of Transportation said Thursday that Highway 20 over the North Cascades may not open until early July.

According to a news release, the extended seasonal closure comes as crews work to clean up winter storm damage.

Crews have begun work to stabilize a slope and clear debris from a rockslide at milepost 131 near Diablo Lake.

The release states that the Department of Transportation is also pursuing contracting options to repair damage between mileposts 142 and 148.

Work to fix that stretch of highway is expected to get underway this coming week.

"We understand how important SR 20 is to travelers, local communities, recreation access and the regional economy," the department stated in the release. "Our commitment today is the same as it always is, and that is to move this work forward as quickly as conditions safely allow and reopen the highway as soon as we can."

At the rockslide near Diablo Lake, crews are rappelling down the slope to carefully examine it for loose rock or debris.

They are using hand tools and compressed air to dislodge and send potential hazards down the slope.

The Department of Transportation noted that this work is the same as the work done along northbound Interstate 5 south of Bellingham following a rockslide in March.

The department noted that there are several reasons the work along Highway 20 could not begin until this week.

Because the elevation of the damaged sites is about 2,170 feet, much of the area stayed buried under snow well into the winter, preventing crews from safely accessing and fully assessing the roadway until March.

Also, crews are dealing with multiple damaged locations spread across about six miles between mileposts 142 and 148, in addition to the rockslide near milepost 131.

The release states that each of those locations has required separate inspections and evaluations by geotechnical and hydraulic engineers before repairs could be designed.

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