- Date: 2010/03/10
- Time: Unknown
- State: Colorado
- Location: Preliminary report: Steep Gully #1, west of Arapahoe Basin Ski Area
- Primary Activity: Sidecountry Rider
- Summary Description: 1 snowboarder caught, partially buried, and killed
- Number Caught: 1
- Number Partially Buried, Non-Critical: 1
- Number Partially Buried, Critical: 0
- Number Fully Buried: 0
- Number Injured: 0
- Number Killed: 1
Events Leading to the Avalanche
- Location Setting: Sidecountry
- Site Elevation: 11600 ft
- Slope Angle: unknown
- Slope Aspect: NW
- Slope Characteristic: unknown
- Avalanche Type: unknown
- Avalanche Trigger: AR - Snowboarder
- Avalanche Trigger (subcode): u - An unintentional release
- Avalanche Size - Relative to Path: unknown
- Avalanche Size - Destructive Force: D3
- Sliding Surface: G - At Ground/Ice/Firm
- Crown Depth: 12 in
- Crown Width: 150 ft
- Vertical Run: unknown
Party consisted of 3 snowboarders, all male in their 20s. None carried avalanche gear.
There is a convex knob in the middle of the starting zone for Steep Gully #1. The first rider triggered the avalanche as he rode over the knob. The avalanche broke to the ground along the convexity. The snowpack was very shallow, and rescuers estimated the average crown depth about 12 inches, and around 24 inches at the deepest. The avalanche was the full width of the gully, but left large areas of hangfire.
The rider was caught and carried for most of the avalanche's run. He was stopped by trees in the upper portion of the runout, and partially buried. His partners descended the path and used their snowboards to excavate him before organized rescue arrived. The avalanche broke trees approximately 6 inches in diameter.
The Steep Gullies are numbered from east to west. The morning of the accident, there was a remotely triggered avalanche in Gully #4 (2' deep, 30' wide, ran about 800 vertical feet). Monday, two days prior to the accident, there was a skier triggered avalanche in Gully #2. The most recent fatality in the area occurred on January 25, 2000.