In late February, a series of avalanches buried half a mile of U.S. Route 395 on the eastern side of California’s Sierra Nevada under 30 to 40 feet of snow and debris. Three weeks and another atmospheric river later, a portion of the highway near Mono Lake is still closed, with no solid estimation as to when it’ll reopen.
The full extent of the damage the avalanches caused to U.S. 395 won’t be known until snow and debris have been cleared, which could take weeks, Caltrans District 9 wrote in an update posted to Facebook. The avalanches that struck the hillsides above the highway between Lee Vining and State Route 167 are expected to have carried rocks, trees, guardrails, fencing and pieces of road along with heavy amounts of snow and ice, guaranteeing that future debris removal will be a lengthy process.
Meanwhile, the closure has cut off the small communities of Lee Vining and Mono City from each other. What was once a short commute between the nearby towns is now a four-hour drive through Nevada, and many people in the area are now unable to attend school, go to work or visit family members, according to the Mono Lake Committee.
Further north, an avalanche on March 12 near Walker Canyon briefly closed U.S. 395 from the Sonora Junction to the town of Walker, effectively forcing the nearby community of Bridgeport into isolation.
“It sucked,” Nakota Weaver, assistant manager at the Bridgeport General Store, told SFGATE. “We closed the store for a cool minute, because we had water leaking through the floor and ceiling.”
On March 7, Caltrans attempted to trigger an avalanche on the portion of U.S. 395 near Lee Vining that was impacted by avalanches in late February, as part of an avalanche control operation. However, snowpack in the area was too firm for the attempt to be successful, according to another Facebook update posted by the agency.
Emergency work to clear avalanche debris from the highway began a day later, but was quickly halted by the warmer atmospheric river that hit the region on March 9.
On March 12, Caltrans started another avalanche control operation using its Gazex system, a process in which tubes are connected to a central gas unit and detonated in order to trigger an avalanche. This time the process worked, and an avalanche was triggered that brought a large amount of snow onto the highway south of previous closures.
Caltrans announced on Tuesday that more mitigation efforts need to be performed before work to clear the highway can continue. It will be at least two weeks after that work starts before U.S. 395 can reopen in any capacity, Caltrans said.