Ever since a thin ledge of pavement was poured along Big Sur’s cliffs, opening the rugged region to tourism in the 1920s and 1930s, California has fiercely fought to save Highway 1.

And Mother Nature just shrugs it off. More than 60 times in its history, the Big Sur route has been buried by landslides. Even before this winter’s storms, about $130 million was budgeted over the next decade for repair, replacement and realignment. Related Articles Big Sur coast grows 13 acres from landslide

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Now, as Caltrans tallies the latest damage — a collapsed mountain on one end and a collapsed bridge on the other — it’s worth asking: Why is this single stretch of rural road so difficult to save? And is it worth it?

The narrow, winding, desolate and fog-draped road, with the Pacific’s booming surf as a soundtrack, has long captured the imagination of a state that romanticizes driving.

“The road’s up there on the wall a thousand feet with sheer drop … and witless cars racing across it like dreams. From rock to rock! ” Jack Kerouac wrote of a route that’s been immortalized in song lyrics, poems and countless Instagram feeds of bug-eyed tourists from around the world.

But this stretch has never carried a lot of traffic. At a canyon near the famed McWay Falls, Caltrans counts about 875,000 to 1.6 million vehicles every year — compared to 22.2 to 31.4 million vehicles along thriving commerce centers such as Santa Cruz, for example.

And Big Sur was long considered an outlandish place to travel. Traveling north from San Diego, the Spanish Portola expedition took one look at the coast, and opted for an inland detour instead.

Yet we’re restless and ambitious. In the late 1800s, a young Monterey-based doctor named Dr. John Roberts, with the support of other local residents, campaigned for a new highway — saying it would both ease life for local farmers and make the scenic landscape accessible to everyone. Roberts estimated it would cost only $50,000. (The final cost approached $9 million.)

Carved out of rock, “it was built in the ’30s out of the Depression, at a time when we were looking for grandiose projects and impressive public works,” said Keith Vandevere, attorney and Monterey County planning commissioner.

Nature was unimpressed — and, like people, is restless. The southern Santa Lucia Range, straddling the San Andreas Fault, is marked with repeated scars, old and new, where the mountains have plunged into the sea.

Why?

There are three reasons, said landslide expert Kevin Schmidt of U.S. Geological Survey in Menlo Park. It is a melange of loose rocks. The topography is steep. And it’s exposed to fierce Pacific storms.

The first recorded slide, closing a 20-mile stretch of road in 1935, happened even before Highway 1 was officially opened.

Over the next half century, slides closed the road no fewer than 53 times, according to “A History of Road Closures Along Highway 1,” a 2001 Caltrans report. There have been at least a dozen slides since then, including this year’s collapses.

State officials had misgivings about the road in 1941, when 160 inches of rain pelted Big Sur, “prompting some state officials to contemplate abandoning the highway altogether,” according to the report.

So routine were slides that Highway 1 didn’t become a year-round route until the mid-1950s. Until then, gates were in place at the northern and southern ends and regularly closed to tourist traffic during the winter.

But its construction changed everything, turning an agricultural Big Sur into a global destination. Tourists say driving Highway 1 — linking Los Angeles and San Francisco — is one of the primary reasons to visit California.

The road also accelerated the development of high-end resorts and more expensive homes, with winter tourism.

And while the pre-highway pioneer families were inured to the isolation of the area, these newer owners depend on reliable access. They have bills to pay, staff to support — demands that amplify the impact of closures on local businesses, according to the Caltrans report.

Every day, the isolated stretch of Big Sur loses $300,000 in revenues, according to Kirk Gafill, manager of the world-famous restaurant Nepenthe. San Luis Obispo and Monterey counties could face a $554 million loss in revenue due to closures, according to a recent study by Visit California, which promotes tourism. The economic impact could ripple out further, if visitors cancel summer plans to the Golden State.

But there’s no quick fix to the two current collapses.

On the north, the downed Pfeiffer Canyon Bridge has been tough to demolish and rebuild due to electrical lines and its location in a pristine and protected state park, said Susana Cruz, a spokeswoman for Caltrans.

It could be late September before the new bridge is open. Until then, the only way to get across is by foot path; there isn’t room in the canyon to install a temporary bridge.

On the south, the massive Mud Creek slide poses a different set of challenges. A USGS analysis shows that 2 million cubic meters of earth have collapsed. That’s 200,000 dump trucks filled with rubble. Highway 1, if it still exists, is buried under 80 feet of dirt and rock at its deepest point.

Previously, Caltrans could correct slides by cutting and bulldozing debris from the tops of the slides and moving it to the bottoms, decreasing the angle of the slopes, so it’s less dangerous and more stable. The 1983 project was the largest earth-moving operation in Caltrans history — and created massive, barren scars.

It also dumped great quantities of sediments into the ocean. But now the Big Sur coast is a protected marine sanctuary.

“You can’t dump it. You have to figure out what to do with it,” said Gary Griggs, professor of earth sciences and director of the Institute of Marine Sciences at UC Santa Cruz, author of the book “Living with the Changing California Coast.”

Smaller slides offer more options, such as walls, buttresses and drainage.

But when a landslide is as large as Mud Creek, such solutions “push the limits of engineering,” said Paul Santi, professor of geological engineering at the Colorado School of Mines in Golden, Colorado.

Engineers have applied different solutions to other large slides.

For the Devil’s Slide project on Highway 1 in San Mateo County, where a 1995 slide caused a five-month outage for busy commuters, 4,200-foot tunnels were drilled to bypass the coast. But that rock — solid granite and not weak sediments — is tunnel-worthy. Even then, the project took years and cost $430 million.

Up in Crescent City, where a four-mile segment of U.S. 101 called “Last Chance Grade” is falling into the ocean, Caltrans will likely move the road away from the coast, at a cost ranging from $680 million to $1.25 billion.

Big Sur’s options seem more limited. Moving or burying Highway 1 defeats its whole purpose. For better or worse, California appears committed to saving the iconic route, even as climate change means wetter winters, and more landslides.

“We didn’t think so much about what it means to maintain these things, once we have them,” said Vandevere. “Now we rely on it and expect it — and it feels like losing to give it up.”