Highway 1 to be rebuilt on top of Mud Creek Slide. Here’s how Caltrans will do it

Drivers on Highway 1 will be going over — not around or through — the Mud Creek Slide when the coast route reopens.

“The new roadway will be realigned across the landslide,” the agency said Tuesday in a news release, adding that the highway will be “buttressed with a series of embankments, berms, rocks, netting, culverts and other stabilizing material.”

Caltrans District 5 spokesman Jim Shivers said in late May that the highway would be closed for at least a year. A more specific timetable for reopening the highway, along with the projected cost, is expected by the end of August, the news release said.

More than 5 million tons of cubic yards of dirt and rock descended on the road 9 miles north of the Monterey County line May 20. Caltrans describes it as the largest ever along the Big Sur coast.

Engineers and geologists have spent weeks conducting tests on the slide to help them determine how best to rebuild the road.

The planned approach, Caltrans said, would allow the agency to rebuild the roadway more quickly and at a lower cost than other options such as “structures, a tunnel or major earthwork that places additional fill into the ocean.”

“This plan is a win-win for the hard-hit Big Sur community and this pristine coastal environment,” said Tim Gubbins, director of Caltrans District 5 (covering Santa Barbara, San Luis Obispo, Monterey, San Benito and Santa Cruz counties). “Our emergency contractor continues working dawn to dusk every day and will continue until we can safely reopen the highway.”

The highway was also closed at another slide site, Paul’s Slide, 22 miles north of the Monterey County line, but Caltrans was able to reopen it there to one way, reversing traffic in mid-July. Flaggers continue to be stationed at that point.

Even with the progress there, a 35-mile section of coastline between Mud Creek and the collapsed Pfeiffer Canyon Bridge to the north remains accessible only via an inland route: Nacimiento-Fergusson Road. Traffic heading north from San Luis Obispo County can go no farther than Salmon Creek, about 5 miles north of Ragged Point.

Final girders for a replacement Pfeiffer bridge are being painted near Stockton and trucked to the site, Caltrans said Monday. Public access there remains on schedule for mid-to-late September, the agency said.

“Our staff has been working hard to tackle the weather-related challenges faced by Highway 1,” Caltrans state Director Malcolm Daugherty said. “We have made tremendous progress on Pfeiffer Canyon, have opened Paul’s Slide and now we have good news on the slide at Mud Creek. Our goal is to reconnect the areas impacted by the winter storms as quickly and safely as possible.”

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