Local Information

Work to remove 20 million-pound rock along SR 503 in Cowlitz County is underway

Wednesday, April 12, 2017 - 11:08

For current highway conditions and construction updates please visit the SR 503 Slope Stabilization project update page. 

Tamara Greenwell, communications, 360-905-2056

YALE – While dangerous rockfall continues to threaten State Route 503 near Speelyai Recreation Road, work to remove trees from on top of the slope began Friday, March 31.

The Washington State Department of Transportation signed an emergency contract with Pacific Blasting & Demolition, a contractor who specializes in precision rock removal and slope stabilization work. Crews will work through the weekend to clear access points onto the hillside, allowing for removal of surface rocks from the top section of the slope.

"This is a major milestone, but there's still a lot of work to do to get the highway open," said WSDOT project engineer Lori Figone. "We've got to remove the large rock slab, assess what's behind it and then stabilize the slope."

WSDOT geotechnical engineers estimate a 20 million-pound rock slab came loose from the hillside, causing a debris slide and closing the highway on Monday, March 13.

Next steps

WSDOT geotechnical engineers will begin drilling to collect core samples to determine the strength of the rock and the location of any fracture points in the hillside. Meanwhile, crews are monitoring the movements of the slope using LiDAR (Light Detection and Ranging) technology.

Due to the current danger of rockfall, the highway remains closed. Drivers can sign up to receive Cowlitz County email alerts about the work, including updates on the progress and news about when the highway will reopen.

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