The Colorado Avalanche Information Center has released the final report on the avalanche that partially buried one of its forecasters earlier this month.

The forecaster, who has not been identified, heard “a loud boom” before the avalanche on Mt. Bethel broke about 40 feet above him on April 8, according to the report. The slide reportedly swept the forecaster down the slope and pinned him against several trees in an upright position with his legs, lower torso and left arm buried under the snow.

“This points out that even professionals with a well-reasoned trip plan can make mistakes,” CAIC Deputy Director Brian Lazar said after the incident. “Though we can do a really good job of reducing the risk of avalanches, you can never reduce that risk to zero when working in a backcountry environment.”

The forecaster had planned a day of field work in the area focused on collecting information on the development of wind slab avalanches in the area and evaluating the sensitivity of a persistent weak layer in the snowpack, the report states.

Before leaving, the forecaster submitted a trip plan that included his route, return time, goals for the day, potential hazards and how he would mitigate risk. He then reviewed the plan with another forecaster as required by the avalanche center’s field safety plan, according to the report.

Around 10:30 a.m., the forecaster left the Herman Gulch trailhead, ascended the east ridge of Mt. Bethel on skis and spent about an hour digging snow profiles and investigating snowpack conditions near treeline, the report states. He reportedly found stiff-wind drifted snow over a hard melt-freeze crust.

After completing his observations, the forecaster began a downward traverse following a gully with a slope between 20 and 25 degrees, the report states. Around 1:30 p.m., the forecaster triggered an avalanche at an elevation of 11,840 feet, according to the report.

The forecaster attempted to ski out of the moving debris, which consisted of large snow blocks, and deployed an avalanche airbag before losing a ski, the report states. He turned to the skier’s right and tried to ski out of the avalanche on one ski but the slide knocked him off his feet and swept him about 50 vertical feet downhill, according to the report. 

When the avalanche stopped, the forecaster was pinned against trees and he attempted to free himself, but could not, the report states. His cell phone was in his left thigh pocket and he used a free hand and ski pole to tear open the pocket and reach the phone – which was damaged in the avalanche and no longer working, according to the report.

The forecaster then tried to reach the equipment in his backpack but the tree he was pinned against reportedly made that difficult. Eventually, he got into his pack and was able to retrieve extra layers, food and his satellite communication device, which he sent a signal from at 4:30 p.m., according to the report. But avalanche debris and tree canopy interfered with the message transmission and it took another 30 minutes to get a message to send successfully.

The Colorado Avalanche Information Center received the emergency transmission at 5:11 p.m. but the forecaster’s trip plan had said he would be out of the field by 5 p.m., so avalanche officials had already initiated a rescue response by then, the report states.

Staff from the avalanche center and a volunteer left the Herman Gulch trailhead at 6:15 p.m. and linked up at the scene of the avalanche with a Flight for Life helicopter that flew in two Alpine Rescue Team members, according to the report.

By just after 8 p.m., rescuers had loaded the injured forecaster into a sled. At about 10:15 p.m., he arrived back at the trailhead where he was transported to the hospital by ambulance, the report states.

The forecaster’s trip plan said he would avoid “steep wind-drifted slopes that can produce size 2 avalanches,” but he misjudged the slope angle of the terrain above where he was traveling, which was 30 to 35 degrees in slope, the report states.

When the forecaster didn’t return as expected, the trip plan he left helped alert others that he was missing. It is recommended that recreationalists always leave a trip plan with someone staying behind anytime they go into the backcountry in Colorado.

The satellite communication device the forecaster had proved to be “crucial in this accident,” the report states. Once the forecaster reached the device, he could call for help and communicate the extent of his injuries, allowing responders to bring the necessary equipment to treat him and evacuate him from the field, according to the report.

Further, airbag packs like the one the forecaster used can reduce the risk of deep burials and may offer some protection from traumatic injury, the report states.

The forecaster was traveling alone and while the avalanche center’s approach to risk management does not preclude traveling alone – or allow it in every circumstance – having a partner creates more options in the case of an avalanche and increases chances of survival, the report states.

“We are grateful that our colleague survived the accident without life-threatening injuries,” the report states. “The accident reinforces the importance of a robust field safety plan, learning from accidents and near misses, and continual refinement of organizational procedures.