PROVO, Utah (ABC4) — US-189 in Provo Canyon was closed intermittently on Tuesday, March 28, as the Utah Department of Transportation conducted blasting operations to remove a rock that was overhanging near the highway.

“Part of a rock wall above the 800 North on-ramp to US-189 in Orem gave way earlier this month due to the unprecedented wet weather combined with the freeze and thaw cycles this winter,” UDOT officials said.

Watch a video from UDOT that captures the rock blasting operations:

UDOT officials say large two to three feet boulders had been breaking off from the mountain, and they had deemed the ramp unsafe until they could bring down an 80-foot rock shelf.

“It’s about 4-5 feet in height and about 10 feet in depth, so it’s a sizable amount of rock that we need to bring down in order to make this road safe for motorists,” said Geoff Dupaix, the region communication manager for UDOT.

UDOT officials closed portions of US-189 three separate times for 20 minutes between 1 p.m. and 3 p.m. on Tuesday. To blast the rocks, workers drilled into the rock shelf in specific areas marked by orange spray paint and installed a detonation device.

“With that drilling, they go to a certain depth and install what we call a shape charge or a detonation device into various holes along that rock face so that, when they’re ready, they can trigger that detonation with the goal of bringing the rocks straight down onto the roadway,” Dupaix said.

There were originally two detonations planned, but the second round has been postponed until Wednesday at 9:30 a.m., officials said.

UDOT crews are hoping to get the ramp reopened by the end of the week.