A section of State Route 1 just south of Big Sur was washed away by a debris flow following heavy rains; the roadway remains closed as Caltrans assesses the damage.
A hillside at Rat Creek near mile marker 30 on Highway 1 gave way Thursday, spilling onto the highway and causing a portion of the road to erode into the ocean, after heavy rains drenched much of the region.
“This particular slide or slip out is within the Dolan Fire burn scar," said Jim Shivers with CalTrans. "So much like what happened in Montecito in Santa Barbara County [in January 2018], if you have a severe fire followed by heavy rainfall there is the potential for debris flow, and we believe that is what happened at the Rat Creek location.”
Shivers said emergency crews are now assessing the damage, with a geologist essentially reading the hillside to figure out the best possible ways to fix it.
"They need to get a sense of where the earth is moving, how it’s moving, will it continue to move?" Shivers said. " Then, once it settles...begin a strategy as to how to build upon this terrain.”
That portion of Highway 1 in Monterey County had been closed to traffic as part of a 45-mile closure ahead of the storm. How long it’ll now remain closed depends a lot on the weather.
“If we can get a good stretch of weather, and we don’t have a heavy dose of rain over the next several weeks or couple of months..the rain can impact the time quite a bit,” Shivers said.
In 2017 a massive mudslide closed Highway 1 for more than a year. Caltrans crews ended up building a new roadway over the land mass the slide brought down.
Shivers said the thing that makes the coastal highway so beautiful is also what makes it vulnerable, as it’s still an emerging coastline.
“ The thing we tell people is that Highway 1 and the terrain on which it sits on is in a constant state of movement and evolution," Shivers said.
For now, tourists who enjoy driving between Los Angeles and San Francisco will have to veer off the Pacific Coast Highway for detours until the roadway can be repaired.