The Cambrian

North Coast readies for major winter storm, potential Hwy. 1 slides

Caltrans and Mother Nature have been busy lately on Highway 1 between Cambria and Carmel, with one brief road closure after a rain-prompted landslide near Willow Creek and the expected, cautionary closure of two problematic slide areas this week.

The winter storm door seems to be wide open now, following a couple of rainy days during Thanksgiving week and the arrival of a potential blockbuster of a storm in the last week of November.

John Lindsey, PG&E meteorologist at Diablo Canyon, said in his Tuesday, Nov. 27, morning forecast that he expects the storm will produce lots of rain, sustained winds of up to 46 mph and wind gusts of up to 55 mph. He predicted from 2 to 4 inches of rain could fall on the Central Coast, and that the Big Sur area could be drenched with up to 6 inches.

In anticipation of the significant storm, Caltrans announced the planned to closure Highway 1 in the Mud Creek and Paul’s Slide areas, which are respectively 8.9 and 21.6 miles north of the San Luis Obispo/Monterey county line at Ragged Point.

Each area will be treated as a separate closure, according to a Caltrans advisory emailed at 9:45 a.m. Tuesday. Spokeswoman Susana Cruz said in the email that the National Weather Service had confirmed that the public should prepare for the popular All-American Road and scenic byway to close mid-morning Wednesday, Nov. 28.

Unmanned gates on either side of Mud Creek and Paul’s Slide will be key locked, and Cruz said that nobody “including emergency services of Caltrans employees will be allowed access until a proper assessment can be made and any necessary cleanup has been completed.”

She added that “Caltrans will have our geotech, maintenance and construction units on call and prepared to inspect/clean up during daylight hours when the storm ends and it is safe to be onsite again.”

Cruz said updates would be provided, and “a final notice will be sent when the roadway closes.”

How long will Highway 1 remain closed at those points all depends on conditions there.

“We are implementing these closures in the interest of public safety,” Spokesman Jim Shivers told The Tribune. “ … Rock slides typically occur during the overnight hours when it rains, so we plan to close the highway in anticipation of significant rainfall.”

With the closures in place, people won’t be able to get to the Carmel/Monterey area from Cambria via Highway 1.

When both spots are closed, the only access to the stretch of Highway 1 in between will be via Nacimiento-Fergusson Road over the coastal mountains to Highway 101.

New policy

Closures are part of a new policy for Caltrans, in which the agency will send out a 48-hour traffic advisory for the Mud Creek and Paul’s Slide areas in advance of major rainfall, so the public has time to make alternate travel plans, obtain supplies and otherwise prepare for a possible closure.

Under that policy, once an advisory period hits the 24-hour mark, the agency plans to either confirm a full closure of the highway or release more information, the agency said.

This is the first season the policy will be in effect for the Mud Creek and Paul’s Slide areas, Shivers said. The policy will continue “until further notice.”

Catastrophic previous slides in those two spots were caused by heavy winter rainfall during 2016 and 2017, the agency said. Paul’s Slide has been active since January 2017. Although there was land movement at Mud Creek about then, the major collapse there occurred on May 20, 2017 , when more than 6 million cubic yards of material buried Highway 1.

Even though the highway has been rebuilt over the slides , “continued movement of the newly formed slopes and landslide features are expected in the future,” said Caltrans District 5 Director Tim Gubbins in a news release. “Closing the highway during significant rainfall events is necessary for the safety of the traveling public and our workers.”

Shivers reiterated that the section of Highway 1 to be closed “remains safe for all users,” and the closures are precautionary, just in case.

The earlier storm

In the 24 hours that overlapped Nov. 21 and Thanksgiving Day, most Cambria areas received between a half inch and an inch of rain. Between Nov. 21 and Nov. 24, Rocky Butte racked up 2.05 inches and other high-mountain areas in the Santa Lucia range also got a couple of inches of longed-for precipitation.

Some North Coast residents were so gleeful about the arrival of the rain that they dashed outside to take photos of drenched posies, cloud-filled skies, determined anglers and raindrops on windows and windshields.

Later, as the bigger storm approached, people battened down to prepare for lots of rain and wind.

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