
All along the ride was clear evidence of how the rain impacted the hillsides. Bulldozer tracks scrapped out a minimum of 12 inches for a shoulder.
This section of hillside shows the slipage from near the ridge at the top as the plants moved down. I believe this to be the section covered in the CBS/KCAL 9 report.

More erosion:

San Gabriel Canyon, Highway 39 and view out to Los Angeles :
