San Rafael Slide Repair: Landslide In San Rafael Endangered Homes

Challenge
A large slide was endangering several homes on a steep slope in San Rafael. The slide plane ran at a depth of up to 30 ft. below the surface and the scarp measured over 200 ft. wide x 300 ft. in length.

Action
The repair called for removal of the slide material, benching into competent bedrock and re-installation of the slide material in compacted lifts. A series of sub-surface drains were placed at the back of the benches. Surface improvements were also installed, including concrete V-ditches and drop inlets to channel rainwater away from the slope. Finally, re-vegetation with perennial rye-grass was installed along with surface erosion protection using jute netting, allowing the grasses to take hold.

Results
This neighborhood is now safe, with the full value of the properties restored. The slide repair has been through many heavy winters with no sign of any further movement or distress.