Tree Well Safety in Whistler

Whistler is an amazing playground for snowboarders but there are risks to this amazing adventure sport. The obvious ones are falling and breaking a bone or getting stuck in an avalanche however a tree well or SIS incident is potentially more dangerous.

Here’s some useful tree well safety tips to keep you safe while riding the mountain this season.

What is a tree well and why can it be dangerous?

A tree well is a void or depression that forms around a tree when snow accumulates around the base, but not under the lower branches or around the tree trunk. These voids are hidden from view by the tree’s low hanging branches and can get progressively deeper as the snowpack height increases. Tree wells are dangerous due to snow-immersion suffocation (SIS)

A rider or skier can fall head first in the tree well and if there is snow on the branches, a fall and contact with the tree will often cause the snow to fall down on top of the person burying them. Like an avalanche, a person can be trapped without fresh air to breathe, leading to suffocation (snow-immersion suffocation - SIS). The majority of SIS accidents happen during or just after big snow storms or storm cycles, the more fresh snow, the higher the risk.

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What should you do if you fall in a tree well?

  • Use a whistle or yell to get your buddy’s attention
  • If you can reach a cell phone call for help (ski patrol or the resort's emergency number)
  • Try to keep your head above the surface of the snow but grabbing tree branches or the tree trunk and avoid becoming inverted. Do anything that will help you sink further into the hole.
  • Stay Calm and conserve air. If you are stuck the more you struggle the further down the hole you can fall. Try to make a space around your face for air. Most people think of an avalanche as the main safety concern in Whistler but with a highly qualified team of avalanche safety crew monitoring the mountain each day, the biggest danger during a big snow season are tree wells.

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What do you do if your buddy falls in a tree well?

With SIS, time is crucial.

  • If you can’t locate your missing buddy, call ski patrol and identify your partners last seen location and start searching for them while you wait for patrol to arrive.
  • If you are wearing beacons, switch to search mode and locate them using the same techniques you would as if in a slide.
  • Try listening for whistling or shouting. If you can visually see your partner’s tracks, follow them.
  • If you find your buddy in a tree well do not try to pull your partner out the way they fell in. Instead, determine where their head is and tunnel in from the side being careful not to knock more snow into the hole.

How can you avoid a tree well incident (SIS)?

  • Always Ride with a buddy. 90% of people that find themselves trapped in a tree well are not able to get out without the help of someone else so having someone ride with you in the trees is a golden rule. Always maintain visual and verbal contact with your buddy while riding and if you do lose contact stop and wait for your buddy. If you can’t find them assume they need your help. You can also make check points for example at a cat track or at the end of each section of the tree run.
  • Carry a Whistler with you and make sure to attach it to a part of your jacket that you can easily reach and get to your mouth.
  • Be aware of the recent snowfall and the depth and avoid tree runs when the risk is high.
  • Assume all trees have tree wells under them, even small ones.
  • Make sure to look at the spaces between the trees not the trees and wherever possible give a wide berth when riding between trees.
  • Ride on groomed areas and avoid deep snow and tree well areas.

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