Foresthill Road Landslide Repair

On April 4, 2006, during unusually heavy rainstorms, a landslide tore away the outside shoulder and one lane of traffic on Foresthill Road, the only significant access to the Foresthill community of 7,000. Placer County called Blackburn Consulting to help assess this dangerous situation and recommend/inspect temporary stabilization measures including: surface drainage improvements, shallow groundwater cut-offs on the inside shoulder, seepage relief drains, and storm-water infiltration reduction for the exposed scarp, shoulder and slope. We performed geotechnical investigation, design and construction inspection/testing for two slides affecting several lanes of heavily traveled roadway. Repairs included reconstructed embankments with keyway in rock and extensive subdrainage. Project challenges included fast-track design and construction to complete repairs before the next winter season, and maintaining two-way traffic on a heavily traveled roadway.

"The County is grateful to have Blackburn Consulting to rely on when we need geotechnical support in a tight time frame. They came though under tough conditions, and delivered a repair for the Foresthill Road that will provide for safe passage for the community of Foresthill.”

 Kevin Ordway, Senior Civil Engineer at Placer County

Location 8.7 miles East of Auburn on Foresthill Road
Agency/Owner Placer County
Timeframe 2006