Why the iconic Big Sur Highway 1 keeps collapsing into the ocean

A stretch of the scenic Highway 1 in Big Sur (California) remains  closed after a chunk of the southbound lane fell into the ocean on March 30 after days of heavy rainfall.

The landslide left about 1,600 people stranded in the coastal community, mainly tourists, according to AP News.

This is the latest of several closures along this touristic highway in recent years, as slides during the rainy season wash rocks down often, according to the L.A. Times.

In fact, the winding roadway has been closed more than 55 times since its completion in 1937 after 18 years of construction, almost entirely due to landslides, local paper Santa Barbara Independent reported.

According to Dick Norris, marine geologist at the University of California, the road was built on highly unstable ground, full of faults and fractures.

The very thing that makes the area a world-famous road trip destination, is what makes the road so prone to rapid erosion, the geologist told LAist.

According to Norris, who calls the Big Sur coastline “a road builder’s nightmare”, much of Highway 1 was built downhill from the location of previous rockslides and once a slide has happened is more likely to recur.

"I think that probably many of the current slides are old slides that are being reactivated," the geologist told LAist.

Right now, Highway 1 is closed from Limekiln Statepark to Lime Creek, in Monterrey County, and it’s expected to reopen by May 25, according to California’s governor, Gavin Newsom.

However, the unstable terrain can lead to a “long-term game of whack-a-mole”, according to geologist Dick Norris, where once a section of the highway is fixed, another inevitably erodes before long.

In Norris’s view, the ideal thing would be to have the road far inland from where it is: “instead of on the cliff, farther up, in towards the interior”, he said.

Of course, if the scenic highway got destroyed and rebuilt farther away from the cliff, it might not be as beautiful as it is now, the geologist recognized.

Big Sur is a 90-mile (145-kilometer) stretch of California’s central coast where often misty, forested mountains descend to the ocean.

The famous highway is widely considered to be one of the most scenic driving routes in the United States, if not the world.

Photo: Lesli Whitecotton/Unsplash

Much of Highway 1 is perched on the edge of cliffs, presenting dramatic views that draw tourists. Roughly 4.5 million to 7 million tourists pass through Big Sur every year, according to the San Francisco Chronicle.

It remains to be seen if the California government can find a long lasting solution to the recurring landslides, or if they’d have to decide on more drastic measures, a question that must be asked, specially when climate change is resulting in more extreme weather patterns.

Photo: A Big Sur vintage postcard (1940)