Boulder falls, blocks lane on Highway 50 near Tahoe’s Cave Rock (updated)
GLENBROOK, Nev. — Nevada Department of Transportation officials were on site Monday, Feb. 22, assessing the scene where a large boulder fell onto U.S. Highway 50 over the weekend. The incident occurred roughly a mile north of Cave Rock — toward Carson City — at approximately 6:30 p.m. Saturday, Feb. 20, according to an NDOT press release. One vehicle was involved in a non-injury accident. Nevada Highway Patrol responded to the incident. Details regarding the nature of the accident were not available at press time.
The boulder broke free from a steep slope — roughly 20 feet uphill from the highway — and rolled across all four lanes of the road before coming to a stop on the other side, blocking the lakeside westbound lane.
“It’s not very common,” NDOT highway maintenance manger Steve Williams said on site Monday, describing the frequency of a rockfall of that scale. “In 29 years of being up here, I’ve only seen a few this size.”
He credited the region’s frequent freeze/thaw cycles for loosening the boulder to the point where it fell down to the highway.
“Moisture in the ground is what does that,” he said. “Basically, it pushes the rock.”
NDOT officials said a work crew had been contracted and was expected to remove the roughly 10-foot long and 7-foot tall, van-sized rock Tuesday, Feb. 23, using a jackhammer mounted on an excavator.
“They’ll break it up and haul it off,” Williams said.
NDOT will not be able to assess the damage to the highway until the boulder is removed.
“More than likely we’ll have to patch that spot and pave it back in,” Williams said.
He estimated that the work would likely be completed by the end of the week, allowing for work crews to reopen the closed westbound lane.
“It’s not going to take a whole lot of material and time,” Williams explained, crediting warm weather for allowing for appropriate conditions to work. “It’s just a matter of getting up here and doing it.”
Reached for comment on NDOT policy, spokeswoman Meg Ragonese added in an email, “NDOT geotechnical engineers and rockfall reduction specialists Hi-Tech Rockfall have closely monitored — and continue to monitor and evaluate — roadside slopes and rock outcroppings for stability.”
Ragonese further described a number of preventative measures regularly undertaken by the department, including the upcoming construction on the tunnel at Cave Rock.
“Safety is our top priority,” she said, also cautioning motorists to always be attentive when passing through areas that could be of concern.