The 1978 Pinecrest Mudslide – Part 1

We should always remember that the very ground we live on was built by massive, violent floods. As the San Gabriel Mountains rise, they shed granite. When it rains hard, those granite pieces flood out of the canyons and wash across our valley in rock-filled waves 20 and 30 feet high. These floods have been going on for tens of thousands of years. So it’s only natural that when we build homes at the mouths of canyons we build them directly in the path of these potentially destructive floods. In 1978, the Genofile family paid the price for that.

The build-out of housing in our valley has crept closer and closer to the mountains. In 1958, a local contractor and his wife, Bob and Jackie Genofile, built a beautiful home on an acre of land on Markridge Road, below Shields Canyon. For a few years the steep land above their house was tree-covered and undeveloped. But in the mid-’60s, a massive development, Pinecrest, was constructed above them with houses being built all the way up to and into Shields Canyon.

Unfortunately, the flood control measures the developer provided at the mouth of the canyon were inadequate. A pitifully small debris basin and dam were built at the upper end of the development at the top of Pine Cone Road. At the very bottom of steep Pine Cone Road was the Genofile house.

Everything was fine for a decade. In November 1975, a huge fire, the wind-driven Mill Fire, swept the San Gabriel Mountains above the Crescenta Valley. It touched a few homes in Pinecrest but the major damage was to the watershed above. Tens of thousands of acres of mountainside were totally burned bare. A flood was inevitable but surprisingly it didn’t happen for almost three years – after everyone had completely relaxed their guard.

In February 1978 a major Pacific storm rolled in dropping nearly 12 inches of rain on our valley. The rain came hard and steady but at 1:30 in the morning on Feb. 10, it really cut loose. For about 20 minutes a solid sheet of water poured onto the still bare San Gabriel Mountains above Pinecrest. In upper Shields Canyon something slipped.

Mud, rocks and water in a huge mass began accelerating down the steep canyon above Pinecrest. The mass grew exponentially as it picked up more rocks and mud on the way down. In the darkness on Pine Cone Road two flood control men had been sent to check the dam and debris basin at the top of the road. Their truck labored up the steep grade through the intense rain. They reached the turnaround at the top. Looking up at the small dam above them they could see things flying over the top – boulders, trees and then a great black wave. The driver whipped the truck around and began speeding down the hill. The black wave was now sporting several cars at the front that were spinning in the dark wall. The debris flow caught them, pushed their truck into a wall on the side, and poured across the bed of the truck. The back window burst in on the men, but they dove out the side door and escaped over a retaining wall.

Down below at the Genofile house things had gone ominously quiet. The concrete flood channel near the family’s house had rumbled loudly throughout the storm as boulders rolled down it. Unknown to the Genofiles, the channel had clogged above them and the backup had joined the black mass coming down the hill. Jackie Genofile and daughter Kim, curious about the quiet, had gone to the front of the house where they could look through the window up Pine Cone Road. In a blue flash of light caused by parting electrical lines, Jackie and Kim spotted what looked like a big black hill moving down the street toward them, pushing a mass of water before it.

They turned and ran down the hall toward the back of the house.

Next week we’ll continue this cliff hanger, as the black wall hits the Genofile house.