Snow fence

From Wikipedia, the free encyclopedia
Large snow fence at Loveland Basin

A snow fence, similar to a sand fence, is a type of fence that forces windblown, drifting snow to accumulate in a desired place. They are primarily employed to minimize the amount of snowdrift on roadways and railways. Farmers and ranchers may use temporary snow fences to create large drifts in basins for a ready supply of water in the spring. In the ski industry snow fences are used to catch snow to increase snow depth in specified areas; a practice which may also be considered snow farming. Snow fences are also used in avalanche control.[1]

Temporary snow fences in North America are usually one of two varieties: perforated orange plastic sheeting attached to stakes at regular intervals (the type usually used for construction site fencing or temporary sports field fencing),[2] or a cedar or other lightweight wood strip and wire fence, also attached to metal stakes.[3] A permanent snow fence generally consists of poles set deeply into the ground with planks running across them,[4] or a line of closely spaced shrubs or conifer trees.[5] A permanent snow fence may be installed where a roadway or railway is subject to predictable snow and wind patterns each winter, such as mountain passes.

Snow fences work by making the wind speed on the downwind side and near upwind side less than that on the far windward side, causing blown snow to settle to the ground, mostly downwind from the fence. Thus, snow fences actually cause snow drifts, rather than preventing them. The fences are placed to cause a snow drift where it is not harmful so that the snow does not drift onto undesired areas, such as roadways.

See also

  • Snow shed, which is designed so that snow collects on top
  • Snow guard, a device attached to roofs to prevent snow from falling on people below

References

  1. ↑ http://geography.about.com/od/physicalgeography/a/avalanches.htm
  2. ↑ Plastic Snow Fencing
  3. ↑ Wooden Snow Fence
  4. ↑ Tabler 1991
  5. ↑ Living Snow Fences
  • Campbell, E. (March 1975). Snowdrift Structures. Avalanche Protection in Switzerland (pp. 103–116). Fort Collins CO: General Technical Report RM-9, USDA-Forest Service.
  • Mears, A.I. (1992). Avalanche Structural Protection in: Snow - Avalanche Hazard Analysis for Land - Use Planning and Engineering. Denver CO: Colorado Geological Survey, Department of Natural Resources, Bulletin 49.
  • Tabler, Ronald D. (1991) Snow fence guide, Strategic Highway Research Program, National Research Council

USACE has developed guidelines and requirements for standing metal seam roofing and the Corps’ Engineer Research and Development Center has recently conducted research in areas of wind/noise mitigation techniques and techniques for constructing snow fences to reduce

External links

Wikimedia Commons has media related to Snow fences.
This article is issued from Wikipedia. The text is available under the Creative Commons Attribution/Share Alike; additional terms may apply for the media files.