Devil’s Slide Tunnel

The Devil's Slide Tunnel on the Pacific Coast Highway is a subterranean structure that preserves a coastline while emboldening economy and safety. California's Devil's Slide Mountain, a geologically unstable mountainside prone to landslides, loomed over a busy 1.2-mile section of California State Route 1, the Pacific Coast Highway. Rockslides and landslides have made for an endless cycle of road repairs, which have closed the road on eight occasions since 1935. The worst damage was in 1995 when the highway was closed for 158 days. But slides onto the roadway continued, creating hazards for motorists and bicyclists. A tunnel was proposed as the best way to preserve the beauty of the coast while ensuring connectivity to San Francisco. Understanding the geology was the key to sustaining a steady excavation rate and completing the tunnel project successfully while never sacrificing safety for speed. Integrated communication between the California Department of Transportation (Caltrans) and the contractor, field personnel, and construction management was a key element to the success of the project as operations required constant excavation changes as new ground conditions were encountered. The first highway tunnel built in California since 1964, Devil’s Slide Tunnel opened on March 25, 2013.


  • English

Media Info

  • Media Type: Print
  • Features: Photos;
  • Pagination: pp 52-56
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 01487530
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jul 15 2013 9:17AM