Highway 39, Crystal Lake Road

Angeles National Forest Landslide of 1971 | Highway 39 Project

The Reinforced Earth Company’s first project in the United States, dating back to 1971. A major landslide in Angeles National Forest created the need for reconstruction of the roadway.

Watch a documentary here, produced by California Department of Transportation »

Several conventional options were considered, but it was ultimately decided to utilize Reinforced Earth, a relatively new innovation at the time. Reinforced Earth allowed the roadway to be built back up to grade in layers, spreading the load of the fill over a wide area. The MSE wall facing used was RECo’s original galvanized steel option, which has since been replaced by precast concrete and wire mesh. A visit to the wall about forty years later in 2010 proved that the structure is still in excellent condition, with a remaining service life far beyond what was assumed in design.