Digging Toward the Light of Devil's Tunnel

Devil's Slide project reaching milestone.

Not far from Pacifica, near Highway 1 and hundreds of feet below Mount San Pedro, workers toil in near darkness.

Beams of artificial light illuminate massive machinery that lumbers past like science fiction creatures.

The blasts of car horns echo down the tunnel walls creating a murky cacophony. This is the world of the Devil’s Slide Tunnel Project.

Crews are cutting away at the mountain to create two 4,200-foot tunnels that will circumvent traffic past the notorious Devil’s Slide. 

This phase of the project is about to reach a major milestone. Crews are just over a hundred feet from breaking through the mountain. They expect to reach daylight on the other side on Oct. 1.

“This is huge,” said Caltrans spokesman Bob Haus. “There are three major milestones: breaking ground, punching through and opening to traffic. So this the second major milestone.”

The $350 million project broke ground three years ago. It’s the first tunnel project for Caltrans in 40 years.
Caltrans engineer Ivan Ramirez called working underground a learning process.

“You know you’re going to encounter different situations where they might slow you down a little bit," he said. "But everybody’s focused on getting the tunnel excavated as soon as possible.”

Once crews pierce the mountain, it will take another two years to finish stabilizing the tunnels and building the roadway.

Inside the tunnel, workers standing on ornate archways added layers of waterproof plastic liners, rebar and concrete to stabilize the already bored walls.

Massive vents pipe in fresh air and water for the workers and the drilling. Ramirez said the underground lifestyle took some getting used to.

“It can be cold at times -- the air is moist.  It can be muddy,” he said. “You really have to love this type of work to be here everyday and we certainly do.”

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