California Route 36 Emergency Landslide Repair
A series of mitigation measures allow for the safe reopening of the highway.
Overview
A section of rock above Highway 36 in Humboldt County, CA, had been a long-standing safety concern for commuters. When a significant landslide occurred, sending debris and trees across both lanes and into the Van Duzen River below, the highway was temporarily shut down.
Key Considerations:
- Mitigation methods were implemented with live traffic (with temporary closures during scaling and helicopter flights).
- Hazardous, loose terrain presented a safety risk to workers during installation.
- Work on both sites had to be completed before the fall season.
- The project required meeting a strict helicopter schedule.
Scope
GRW was retained under an emergency contract to assist in the development and construction of a series of mitigation measures at two locations along Route 36. A combination of hazard mitigation techniques and drapery installation was required to efficiently restore safe access to the roadway. the project.
Method
We worked with the owner to develop constructible solutions based on the conditions at each site.
- Site 1 required tree falling and slope scaling with approximately 50,000 sq ft of cable net drapery installed. Two post-elevated drapery systems were installed midslope to create a three-system “mousetrap,” funnelling rock into a ditch at the bottom along 500 ft of slope.
- Site 2 required tree falling and scaling with approximately 50,000 sq ft of cable net drapery installed.
Results
The project was completed on budget, and full access was restored to the roadway within the projected timeframe.
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When your project is high elevation, high risk, or both, you want the most experienced team on the job. Our seasoned technicians are ready to take on the most complex geohazard projects to keep your site and community safe.
