Tuesday, September 1, 2015

Snowfences, When and Where

Someone asked how we make decisions about when and where we put snowfences. I should probably start with how snowfences work. Wind blows snow crystals near the snow surface. When those blowing crystals come to a fence, they tend to rise up and over the fence. The fence acts like a wind break with calmer air on the leeward side of the fence. When the snow crystals hit that calmer air, they fall to the ground causing a snow drift. The closer a fence orientation is to being perpendicular to the predominant wind direction, the more snow the fence will catch.

We build fences in places we would like to put a snow drift. This could a wind swept area or a heavily trafficed area. In most, but not all cases, snowfences are built in places that can be accessed by the snowcats. The cats first pack and then sometimes push the snow to its most preferred spot. 

Snowfences are an absolutely critical component of our snow farming, snowfencing, snow grooming, snow making program.

Below is a fence extension under construction at the Long Chute access to West Zuma. This fence in particular is used to put snow in a key hiking area. Very importantly, most of the snow drift caught by this fence is pushed down to the top pitch of Larkspur.