Massive Mud Creek Slide on Hwy. 1 must be seen, heard and felt to be believed

Engineers don’t know how they’re going to restore a nearly half-mile segment of Highway 1 that’s been swallowed up by a falling mountain, but they do know one thing: It won’t happen soon.

What they’d hoped would take weeks “is going to be months,” Susana Cruz, Caltrans District 5 public information officer, said Wednesday at the site of the massive Mud Creek Slide, about 9 miles north of the Monterey County line.

Will it be done this year?

“Maybe not,” Cruz said. “We’ll have a better idea at the end of the week.”

During a tour of the area Wednesday afternoon, Cruz and two Caltrans engineers assessed the slide and what could be done to fix it.

Will a new road be built over the collapsed hillside? Will they dig their way down to what’s left of the highway buried underneath? Is there even anything left of that highway? Those are questions that just don’t have answers yet, they said.

The scope of the slide

Even before Saturday’s slide — actually a series of four slides — Caltrans had its hands full. The mountain had been giving way in fits and starts since heavy rains in January, damaging the road and forcing Caltrans to close it to northbound traffic at Ragged Point.

But Saturday’s event took it to a whole different level. Previous slides had involved “sometimes hundreds, sometimes thousands of cubic yards” of earth, Cruz said. “But this was millions.”

Part of the highway had collapsed in earlier slides, leaving only one lane of roadway intact at one point. Now, there’s no sign of even that. It’s all buried under tons of dirt and rocks that washed down over it like a gigantic earthen waterfall, pouring out into the sea and creating a new peninsula in the process.

Restore the old road? How?

“Imagine with all that weight, if there was only one lane left, I’m sure it’s gone,” Cruz said.

And it’s not over yet. Looking up the mountain from near the base of the slide Wednesday, it was easy to see more debris tumbling down, disappearing in clouds of rising dust. A short trek up a gravel access road added a soundtrack to the visuals: The falling rocks sounded eerily like raindrops pattering on the roof of a metal shed.

“It’s actually pretty mesmerizing to watch this when it’s trickling down,” construction inspector Bret Haney said. “It kind of messes with your equilibrium, because it’s moving all around you.”

Some of them are probably no bigger than those raindrops, but others are gargantuan.

The newly formed peninsula is home to a large number of massive boulders that have been deposited there by the slide. Haney and resident engineer Rick Silva estimated they might weigh between 20 and 25 tons.

The road now ends abruptly at the slide and re-emerges about four-tenths of a mile to the north. But even the segment of road that hasn’t been buried feels different to walk on. It’s uneven now close to the slide, almost as if it’s been undulating.

“This whole road has been kind of lifted up,” Haney said. “It’s been built on the top of loose material, so when more loose material comes down, it kind of shifts and takes the road with it.”

The best-laid plans ...

Before Saturday’s slide, Caltrans had hoped to stabilize the road and get it reopened this summer. Workers, however, had been in a constant battle with new debris coming down the hillside.

Cruz said Silva would bring crews up to the site at 5 a.m. every morning to clear the road, but the next day, it would look as if nothing had been done.

“We called it Groundhog Day,” said Silva, a 1983 Coast Union High School graduate. “It was the same every day.”

Still, Caltrans tried to keep the road clear for limited local access and had a plan to repair it.

“There had been hope for a sidehill viaduct to shore things up,” Cruz said, “but Mother Nature had her own ideas.”

Cruz said Caltrans workers didn’t see Saturday’s slide happen; they were alerted by area residents who heard it … from 2 miles away.

The Mud Creek Slide is one of two major slides that have affected Highway 1, along with Paul’s Slide about 12 1/2 miles to the north. Together, they bracket a section of road that includes a few campgrounds and the service stop of Gorda (all still open), and which is accessible primarily via Nacimiento-Fergusson Road from the east.

Caltrans has been able to provide limited access for deliveries at Paul’s Slide for an hour or two each day, but even that has been jeopardized in recent days by new slide activity there. Caltrans has pushed back its target date to reopen that section of road from June to early July, Cruz said.

Paul’s Slide is a challenge, but it pales in comparison to Mud Creek. Silva and Haney estimated about 200,000 cubic yards of earth is involved at Paul’s Slide, compared with five times that much — a million cubic yards — at the Mud Creek site.

“You look at that and think it’s big until you get here,” Silva said, comparing the two.

Worst slide since 1983

Cruz said the Mud Creek Slide is worse than anything that occurred during the El Niño year in 1997, when severe storms caused some 40 slides along the highway. The biggest of those, not far from the Mud Creek Slide, was called the Duck Pond Slide, she said, and it didn’t measure up to this one. You’d have to go back as far as 1983 to find anything comparable, she said.

One major contributor to the slide’s severity is its geology.

“I think what makes this unique is that it had springs coming out of it, so it never really dried,” Cruz said. “It’s not uncommon for slides to take place in May. It dries up, and then it cakes up and slides down. But in this case, it just kept slushing and falling.”

How much more of the mountain will give way?

“There’s more stuff that can come down,” Cruz said. “But we just don’t know how much that would be.”

The Mud Creek Slide actually consists of five slides, four of which moved Saturday. Caltrans is working to gather more information by drilling into the earth to find out the depth and composition of the fifth: Arleen’s Slide.

There’s a story behind that moniker.

“Everything’s got a name up here,” Haney said. “You’re looking at a map, and you’ve got dot after dot with names of slides for miles. Arleen’s Slide is named for a flagger who was standing by the side of the road when part of the hillside fell away.”

The flagger was unhurt, and Arleen’s Slide is stable now. For the moment.

Meanwhile, the slides that fell Saturday have created a whole new coastline — that small peninsula that Cruz estimated extends 1,500 feet out into the ocean. Workers have dubbed it “Point Rick” in Silva’s honor, with some joking that it could be a great new spot for surfing.

That would be fine with Silva, who likes to ride the waves himself: “I hope I’m the first one to surf it,” he said Wednesday.

However long it takes, Caltrans is determined to reopen Highway 1.

“It’s easy to put the road in, but making it safe for the public is the hard part,” Haney said. “Caltrans has got a lot of people on this right now trying to figure this thing out, believe me.”

Stephen H. Provost: 805-927-8896, @sproauthor

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