FRISCO — Two state workers were injured early Monday morning when their avalanche-blasting equipment failed as they tried to ensure safe conditions for drivers along U.S. Highway 6 over Loveland Pass.
According to Colorado Department of Transportation spokesman Bob Wilson, an explosive charge appears to have exploded in or near the barrel of the “avalauncher” cannon the men were using to intentionally trigger snow slides. Details are slim, but Wilson said CDOT will do an internal investigation.
CDOT officials haven’t released the names of the two men. One works for the state transportation agency, the second for the Colorado Avalanche Information Center. St. Anthony’s Medical Center in Denver lists the CDOT worker serious condition, while CAIC avalanche expert is in fair condition.
The accident happened between 4 a.m. and 5 a.m. during a routine cycle of avalanche control work in the Sisters Area, where the avalanche hazards are well-mapped. CDOT closes the road during the earliest daylight hours when traffic is low to clear the slide paths. The pneumatic cannon can send two-pound loads of petolite explosives into the starting zone of avalanches from a safe distance. The guns are also used at ski areas to blast remote terrain.
Even just a few inches of snow can overnight build into three-foot-thick crumbly windslabs — snow that, in a year like this, could easily come tumbling down onto the highway. Wilson said CDOT already has performed more than 40 avalanche control missions around Loveland Pass covering 24 named avalanche paths. Some of those missions include dropping even bigger loads of explosives from helicopters.
Personnel from the Colorado Avalanche Information Center are interested in the highway blasting operations because the results help show current conditions. The observations are fed into a data network that helps generate sophisticated avalanche forecasts for specific mountain zones.
Accidents involving avalanche-blasting equipment is rare, but they are taken very seriously when they do happen, said Dale Atkins, a CAIC veteran and trained avalanche investigator who now works for RECCO, a company that makes avalanche safety gear.
The last serious accident involving a CDOT avalanche crew was in the 1990s, Atkins said. That accident prompted the state highway department to adopt new regulations, including a requirement for remote firing to avoid risks of an in-barrel detonation.
“In my opinion, CDOT was doing something right, because if it was an in-barrel detonation it can kill people,” Atkins said.
Throughout Colorado history, transportation across the Rockies has been risky business. Pioneers starting up the Front Range canyons under a warm Chinook surely must have foundered and even perished in the massive waves of snow that periodically thunder down high country peaks.
Scores of railroad workers faced extreme avalanche hazards during the settlement era as they tunneled through 20-foot berms in the canyon between Frisco and Copper Mountain.
But cars didn’t even come into the picture until the 1940s. Before that, many passes were simply inaccessible in the winter, Atkins said. Altogether, drivers who venture up to Vail or Winter Park run a gauntlet of more than 100 named avalanche paths, added Atkins, who created a highway avalanche atlas for CDOT about 15 years ago and also helps maintain a historical avalanche data base for the avalanche center.
Statewide, there are about 600 paths that affect state and federal highways, with many more poised above local and private roads.
“In any given winter, 10 or 15 are the problem ones, maybe another 20 in exceptional years,” Atkins said. Given the many thousands of explosive launches, the equipment has proven reliable over the years, he added.
The first documented avalanche related death of a highway worker on Loveland Pass was in 1944, when a plow driver who was cleaning avalanche debris off the road was swept down by a secondary slide.
In 1957, a highway worker and a Disney cinematographer were killed as they tried to film an avalanche on Berthoud Pass. And in 1992, Eddie Imel was killed by the infamous East Riverside Slide on Red Mountain Pass, the third CDOT worker to die on that dangerous stretch of highway.
The American Avalanche Association maintains a memorial list of 56 avalanche professionals who have died in the line of duty. They include ski patrollers, Forest Service snow rangers and highway workers.
[ Photos. Top: The snout of a May 2011 wet snow avalanche rests just above Interstate 70 west of Frisco. The slide broke 30-year-old trees like toothpicks and left a 30-foot deep debris field on the bike path to Copper Mountain. This is the “Big Mike” slide path that bedeviled early railroad travelers between Denver and the mining camps. Sometimes passengers got out of the train to help dig through the avalanche debris so the train could proceed. Bottom: An ‘avalauncher’ in action at Arapahoe Basin Ski Area, as ski patrol experts fire explosives to intentionally trigger slides on the East Wall. ]