photo essay by Karl Weatherly
In the late-evening light of August 17, 2007, the sky above Warm Springs Creek was volcanic. A day after lightning sparked the Castle Rock Fire, a thin, black, plume of smoke had expanded into a towering, ashen column. Ketchum photographer Karl Weatherly could see the cloud, but he wasn’t panicked. It was just another tranquil summer evening in Ketchum’s Board Ranch—dinner time—and Weatherly was in the mood for barbecue.
Twenty-four hours later, on the ridges above his neighborhood, fir trees burst into flame. An orange glow lit the night.
"That’s when we started talking about the lines that would open," Weatherly said. "I was worried about my house, but the good skiers who live here, we talked among ourselves about the tree skiing."
Sunday afternoon brought the government truck, megaphones blaring: "By order of the Governor, you are being evacuated." Weatherly had two hours. He gathered his equipment, the Canon 5D and telescopic lenses that, months later, would capture proof of epic runs, the sweet collateral of a ravaging blaze.
Scoping lines in mid-January, Weatherly kicked off a slide, easily fatal at 20-inches deep. Ketchum’s Board Ranch was getting clobbered with avalanches. Bulldozers clearing debris were a common sight on the dirt road that month. Skiing the burn would have to wait.
By late-February, the snowpack was stabilizing. Equipped with the necessary backcountry gear—transceiver, shovel and probe—Weatherly and professional telemarker Danny Walton found countless lines. "I’ve spent 15 winters in Sun Valley. It was the best I’ve experienced here," Weatherly said. The added gift of cold, light snow edged the skiing into sublime territory.
"It’s real mystic," Walton said of the burn. There is stark contrast here, both visual and metaphysical. The skier’s euphoria is set against the very real danger of skiing out of bounds. Then there is the obvious black and white of it, the yin and the yang and the surreal relationship between fire and ice.
At your own risk
Hot Smoke, Cold Smoke and the Hidden Dangers in Burn Zones
Avalanches and wildfires, which together kill more people in the West than all types of natural disasters combined, are surprisingly interrelated.
Avalanches, which can only occur on slopes about 30 degrees or steeper, knock down trees and create clear paths within timber stands. These discontinuities slow and weaken wildfires. But when summer fire destroys vegetative hillside cover, avalanche danger grows.
Prior to the Castle Rock Fire, the slide risk on treed slopes was reduced by several factors: Closely spaced trunks anchored the snow pack; clumps of snow falling from branches penetrated the snow surface and reinforced it like rebar; and dense timber stands near ridge tops disrupted dangerous wind patterns. But today, with most of the canopies gone and many of the trees fallen, bigger and more frequent avalanches are more likely. And as standing dead trees rot and fall, slides will continue to rumble through the burn zones.
Before Castle Rock, sage also reduced avalanche risk. Big Mountain Sage grows about 24 inches high and can anchor two feet of snow or more. Today, many slopes once covered with sage are smooth and more apt to slide. Fires can also destabilize soil and cause land slides with resultant steep headwalls that can act as avalanche-starting zones.
Slopes burned by the Castle Rock Fire are at a substantially higher risk for increased avalanche activity. How many more avalanches actually occur depends on the interaction of weather and the fire-affected topography. The Sawtooth Avalanche Center and the Sun Valley Ski Patrol will consider these variables when analyzing the danger this winter. Out-of-bounds skiers and snowboarders would be wise to do the same before ripping the burn.
— Doug Abromeit
Doug Abromeit is the director of the Forest Service National Avalanche Center based in Ketchum. For daily avalanche reports, call 622-8027.