Contractor begins scaling process as WSDOT works to reopen SR 20 near Diablo Lake

A contractor for the Washington State Department of Transportation (WSDOT) has begun the scaling process on State Route 20 (SR 20) near Diablo Lake.

After getting the equipment on site, the contractor began inspecting the slope and dislodging loose rocks and debris, according to an X post from WSDOT on Wednesday.

UPDATE MAY 6: After getting equipment on site, our contractor began inspecting the slope and dislodging loose rocks and debris. This delicate process, called scaling, will continue for several days.

SR 20 remains closed from MP 130-156. No access for hiking, biking or camping. https://t.co/rvXKbktSTm pic.twitter.com/DJxDY35zcJ

— WSDOT North (@wsdot_north) May 6, 2026

The scaling process will continue for several days, WSDOT stated.

SR 20 closed due to rockslide

SR 20 is currently closed from the west side of Colonial Creek Campground (milepost 130) to Porcupine Creek (milepost 156) due to a rockslide. During the closure, there is no access to hiking, biking, or camping.

UPDATE MAY 5: We began work to stabilize the slope & clear debris on SR 20 near Diablo Lake (MP 131) today. This is the first of two emergency contracts needed to repair & reopen North Cascades Hwy.

SR 20 remains closed from MP 130-156. This INCLUDES bikers, hikers and campers. https://t.co/medBvGVRYh pic.twitter.com/NIGQUit1Gt

— WSDOT North (@wsdot_north) May 5, 2026

The highway has been closed since March 17, and WSDOT said reopening it will require two repair projects.

The first project focuses on slope stabilization and debris removal, while the second focuses on rebuilding the embankment and restoring more than 1,000 feet of undermined and collapsed roadway.

WSDOT said it is working to open the North Cascades Highway as quickly as possible.

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