West Coast
Debris washes over the catchment area at Paul’s Slide last week. (Photo: Courtesy of Caltrans)

CA - Slip sliding away: The name of the game on scenic Highway 1

BIG SUR — The engineers and laborers who constructed California State Route 1 from Carmel to San Luis Obispo County beginning in the 1920s knew the road was fraught with peril. But they did it anyway. Coastal communities in the area needed better access to health care and other resources.

Engineers and prisoners alike risked life and limb as they built the two-lane highway into the majestic coastal cliffs of the Santa Lucia mountains. The 18-year project eventually connected San Luis Obispo to Carmel via the seaside, where the geology makes the road inherently susceptible to landslides. The 1937 grand opening even included a symbolic blasting of a boulder, which the governor cleared from the road with a bulldozer. It was the first of many to come.

Now, incessant storms are causing landslide trouble on Highway 1. Again.

Multiple problems

A 45-mile section of Highway 1 extending from Deetjen’s Big Sur Inn in Monterey County to Ragged Point in San Obispo County is currently closed due to landslides, with no estimate on when it will reopen. And residents, businesses and Caltrans crews along the Big Sur coast are bracing for more geological activity as winter storms continue rolling in.

Closures like this along the Big Sur coast are not uncommon. Residents and businesses aren’t surprised when they are temporarily cut off from the world. Caltrans engineers know they must move mountains off the road. Repeatedly.

But nobody gives up on California’s crown jewel highway, which is recognized by the U.S. Department of Transportation as a National Scenic Byway. Laborers, who seem to be working continuously to repair damage and rebuild sections after landslides, are lauded as heroes, and locals host celebrations for reopenings.

‘Challenges and rewards’

“A ribbon of highway on the edge of the continent presents challenges — and rewards,” said Kevin Drabinski, the Caltrans District 5 public information officer.

“We make these closures for the safety of the traveling public. It’s an international travel destination, and, just as important, it’s home to communities and businesses. So we try and do the best we can to keep it open,” he said.

Landslides come with the geology of the area. “It’s old ocean floor stuff that makes up a lot of the California coast that’s been accreted or pushed up on the continent, so it’s been faulted and folded and distorted and weakened,” said Gary Griggs, a professor of Earth Sciences at UC Santa Cruz.

Landslides on Highway 1 usually happen during storms, when water hits soil, making the soil heavy, lubricated and more fluid. Gravity sends chunks of mobilized mountainside plunging from steep, sweeping cliffsides into the crashing waves below — or onto the highway.

Caltrans prepares for winter storms in the fall. Crews inspect and clean out culverts, which Drabinski describes as the “unsung heroes of Highway 1.” Some workers even rappel from the cliffs with picks and other tools in hand to dislodge loose rocks. Worker safety is always a priority.

The goal is to make the cliffs as stable as possible going into the winter. “We put special focus on areas that are downslope of the Dolan fire burn scar,” said Drabinski. Previously burned areas are especially prone to slides when the rains start.

The precarious road has been closed due to landslides dozens of times since it first opened in 1937. The road closed 55 times between 1937 and 2001, according to a 2001 report.

Read more.