Detailed Accident Report
Submitted By: Dale Atkins CAIC
Place: La Plata Peak ? Sawatch Range
Summary: 2 hikers caught, 1 injured, 1 buried and killed
La Plata Peak ? Sawatch Range
March 20, 2004
2 hikers caught, 1 injured, 1 buried and killed
At 3:15 Saturday afternoon two climbers were caught in a small avalanche on the west side of La Plata Peak (14,361). Located about 6 miles southwest of the village of Twin Lakes (or 7 miles southeast of Independence Pass), La Plata Peak is the State's 5th highest 14,000-foot summit.
At 0730 three Colorado Springs' men left their car for a day-long climb of La Plata's north-northwest ridge. Using snowshoes they made good time on the frozen, firm snow. On Friday they had called Colorado Springs avalanche hotline; they carried probes, shovels, and other basic outdoor gear. The 4000 vertical foot climb took longer than expected and they reached the summit at 2PM. This was about an hour later then when they had hoped. They spent a short time enjoying the summit views and warm weather.
The trio knew they were in for a long day. They felt a short cut down the west face by sitting glissade would greatly speed up their descent. Using their ice axes to control their speed the men found the snow on the upper slopes to be firm and crusty and perfect for glissading. They glissaded two sections and then traversed over to another snow-filled gully. The snow surface was still crusty but just starting to become moist.
The victim, a 22-year-old man had already descended a long ways down slope when his friend started his third glissade. This man had only gone a short distance when the snow fractured around him. He tried to self arrest but was quickly tumbling out of control in the mass of sliding snow. A third friend, a bit further back was not caught.
When the avalanche stopped the survivor -- battered on his face and head -- was partly buried. In a Colorado Spring Gazette interview he described the ride: "It was like being thrown down a flight of stairs underwater, contantly being pushed and tumbled and turned." He lost his pack in the slide but was able to dig himself free and started looking for his buried friend. It took nearly 40 minutes for their third friend to descend the icy and rocky slope to the debris. The pair found ski poles, a snowshoe, and a shovel handle, but no friend. It took a while for the third man to The men searched for two hours without success. Battered, weary, and faced with a lonely hike out it took the pair nearly six hours to reach their car. The snow in the valley was wet and cohessionless, with every step they would sink to their knees or deeper then the heavy, wet snow would pile back on top of their snowshoes.
On Sunday morning the Chaffee CountySheriff's office mobilized the Chaffee County Rescue Group, Lake County Search and Rescue, and mountain rescue teams from Western State, Crested Butte, and Summit County. A Flight for Life helicopter helped to ferry rescuers to the scene.
An avalanche rescue dog from Crested Butte had numerous alerts including an alert that directed a probeline to the right spot. The wet snow was very dense and the surface layer had refrozen over night. Several rescuers broke collapsible probes in the hard debris. The victim was found shortly before noon, buried 3 feet down.
This combination hard-slab and wet-slab avalanche triggered by the climbers was classified as HS/WS-AF-2-G. It was small-sized relative to the avalanche path, and the fracture line was only 16 inches deep. The avalanche initially released in dry snow at 13,200 feet -- the surface was just starting to become wet -- but turned into a wet-snow slab avalanche at about 12,800. The avalanche fell a total of 1600 vertical feet, stopping at 11,600 feet. On its way down the wet snow entrained dirt and rocks. At its widest the avalanche was 100 feet across, and in the gully it narrowed to as as little as 40 feet. The slope angle at the fracture line was 37 degrees. Though the mountain faces west the side of the gully where the avalanche released had a northwesterly aspect.
On Friday one of the trio called our Colorado Springs Hotline message. The message is posted between about 6;30 to 7:00 AM. After the weather section we started our snow and avalanche report with "Spring conditions rule. All mountain areas will see an increased threat of wet-snow avalanches in the afternoon and evening hours." Our danger rating as of Friday morning was "overall LOW morning and moderate afternoon, because of wet-snow instability." Triggered avalanches were possible.
The snow cover in the La Plata Peak area is very shallow. On Saturday morning a nearby SNOTEL station that remotely measures snow-water equivalent was reporting only 60% of average. At 10,000 feet only about 1 foot of snow covers the ground and at treeline snowcover is only 3 feet. The entire snowcover below treeline is composed of well developed, cohessionless depth hoar (facted, sugar-like grains). The dry conditions and warmth were important factors in this accident.
Snow depths are about half of what one would normally find in the area. In Colorado a shallow snow cover is a weak snow cover. In shallow snow the additional weight of a person more easily affects weak layers, and also shallow snow warms and turns wet faster.
Early Saturday morning a light freeze created a thin but stout crust that supported the weight of the climbers while they travelled on snowshoes. With an early start and a north-facing ascent route the climbers would have never encounted thaw conditions. (On Sunday by mid day the north aspects were wet to treeline.)
The group reached the summit later than expected and knew the snow would be turning wet. But as they descended from the summit the snow at the highest elevations was still "firm and crusty." These conditions may have given the hikers false confidence and lured the men even lower.
The men were spread out -- vertically -- on their glissades. The victim was about "400 yards" below his friend when the second man started down. Unfortunately the lower man probably did not realize what had happened above him. If he did, he may have already been bogged down in wet snow and could not escape.
We will post more information as it becomes available.
On March 19, 1960 a climber was buried and killed in an avalanche low on the mountain after a failed attempt of the Ellingwood Ridge.
Atkins and Sawtell, 3/22/2004, updated on 3/23/2004