Debris from an adjacent hillside fell approximately 2,000 ft. above SR 504-Spirit Lake Memorial Highway-and covered the roadway with rock, mud, ice and water causing catastrophic damage to the Spirit Lake Outlet Bridge, which connects travelers to the Johnston Ridge Observatory, near Mt. St. Helens. (WSDOT photo)

Shortly after 9 p.m. Sunday, May 14, debris from an adjacent hillside fell approximately 2,000 ft. above SR 504-Spirit Lake Memorial Highway-and covered the roadway with rock, mud, ice and water causing catastrophic damage to the Spirit Lake Outlet Bridge, which connects travelers to the Johnston Ridge Observatory, near Mt. St. Helens.

The slide washed out an 85-ft. bridge, damaged the roadway, and severed power to Johnston Ridge Observatory. No one was injured because of the incident and 12 members of the public who were stranded overnight at Johnston Ridge Observatory were safely flown out the following morning.

WSDOT and federal agencies are working together to assess the slide area and develop next steps. Due to continued landslide instability, data collection is being conducted from the air.

WSDOT scheduled a fixed wing aircraft LIDAR (laser imaging, detection and ranging) flight over the area on Friday, May 19 to gather preliminary data. This was an important step in collecting data to help inform when on-site access, cleanup and work can begin. It is too soon to tell when crews may be able to access the slide from the ground or when the highway may reopen.

In coordination with federal agencies, the Washington State Department of Transportation closed the highway to all travelers. Travel along SR 504 remains open with multiple scenic viewpoints up to milepost 43 near the Science and Learning Center at Coldwater.

There is currently no access to Coldwater Lake, the Hummocks Trail and the Johnston Ridge Observatory. For safety, WSDOT and federal agencies strongly encourage people not to venture beyond the highway closure location due to the severity of the unstable hillside.

The USDA Forest Service is in the process of exploring alternative options for visitors who would like to visit the north side of the Mount St. Helens National Volcanic Monument this summer and develop a plan to manage the influx of visitors in a safe manner. Several other visitor centers located along SR 504 remain open to the public, including scenic viewpoints where visitors can see Mount St. Helens and learn about the history, eruption, and recovery of the volcano. As the snow melts and forest service roads open for the season, additional sites on the Monument and surrounding communities will begin to open for visitors to explore.

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