LA JOLLA, Calif. (KGTV) — City crews have started emergency repairs to an unstable cave located underneath a busy La Jolla street.

Coast Blvd. was closed late Thursday after experts found weaknesses in Cook's Crack, a sea cave underneath Coast Blvd. near Cave St.

"We're starting to see above ... the looser, weaker material. That's a trigger right off the bat that, 'Oh my God, we don't have the beefy rock bridging across anymore. So that's what got out attention," said James Nagelvoort, city public works director.

RELATED: La Jolla streets closed for emergency stabilization of Cook's Crack cave

The discovery came as crews prepared to repair Coast Blvd. Assessors discovered that if too much weight is above the cave or heavy seismic vibrations hit the area, the road could collapse, according to the city.

A crew from Texas was called to lead the project, driving overnight to La Jolla Friday.

Crews plan to first fill the cave's cracks with an eco-friendly polyurethane mix to strengthen the dirt. The next phase will be to clear out all of the water and fill the cave with a concrete mix.

Construction is expected to last about six weeks, closing parts of Coast Blvd. and Cave St.

Cook's Crack is located in the area between La Jolla Cove and the popular Cave Store. The strip of road leads down to seaside restaurants and parking for many tourists and residents.

The project required the city to quickly close the road before locals realized what the issue was, though businesses and residents were allowed to pass through the area Friday.

"They said there's been some shift in the road itself," David Heine, owner of nearby Brockton Villa Restaurant, told 10News. "The busiest two weeks of summer, literally ... Obviously safety's the number one concern for any city, and we respect that."



