Snow Fence Installation
How Does a Snow Fence Work?
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By Rebecca Sanderson – What is a snow fence? How does it work, and is it feasible for you to build? A snow fence can be as complicated or as simple as you want it to be. There are a few simple rules to follow, but a lot of choice when it comes to your unique circumstances.
When driving along a highway in winter, you might want to look around (safely, of course) for fences running parallel to the road. If those fences are not normally there in summer, then you may be looking at snow fences. In many places, the highway department uses signature orange plastic fencing with a large mesh pattern, set back quite a bit from the road. In other places, the snow fences are larger and more permanent. These may be made of wood, such as along Highway 80 in Wyoming. Some snow fences are living, made from trees or shrubs. While these may take a few years to be effective, they take less maintenance than most other snow fences.
How Does a Snow Fence Work?
A snow fence is used to help prevent drifts of snow from forming across roadways. This does not happen because the fence stops the snow. Rather, the fence slows down the wind as it passes through, causing it to drop more of the snow on the downwind side of the fence. That is why they are set so far back from the road; so there is room for the snow to fall before reaching the road. While most snow fences are made to prevent snow from building up as much on roadways, they can also be made to direct snow to accumulate in certain areas for water use in warmer weather.
There are so many options when it comes to snow fences on your homesteading land. Your local hardware store is likely to have the supplies for a snow fence, whether you choose plastic mesh or to build a wooden fence. As long as the open space is around 40-50% of the total area of the fence side, it will work as a snow fence. You want a little bit more solid (plastic or wood) than open space in the fence to slow down the wind better. When you secure the fence, remember that it will be placed against the prevailing wind and must be strong enough to withstand that. Metal T-posts are a lot stronger than U-posts and make a good base for plastic mesh fencing. You shouldn’t need much else outside of your basic farm tools and equipment.
Logistics and Installation
When planning a snow fence, there is a little bit of math involved. A higher fence will naturally cause more snow to drop in the drift area. However, a taller fence also extends the area in which the snow will be dropped. A general rule is that a fence must be 35 times its height away from whatever it is protecting. If a fence is one meter high, then it must be 35 meters away from the road. A two-meter-high fence would need to be 70 meters away, and so forth.
The fence must also have a little distance between the bottom of the fence and the ground so it does not simply become buried beneath the snow. A snow fence needs 10-15% of its height to be the space between it and the ground. Terrain that is rougher with rocks, dense grass, or small shrubs needs higher clearance. For example, if you had plastic snow fencing four feet high, you need five to seven inches of clearance beneath.
For the posts of a snow fence, 1∕3 of the post needs to be buried. Your four-foot fence over five inches of clearance would need a seven-foot post, set two-and-a-half- feet into the ground. Posts should also not be too far apart; highway departments recommend eight feet apart using the four-foot fencing. However, the end posts are only placed six feet away from the last post, and they are further secured with wire staked into the ground for added stability.
Be sure that you attach the fencing on the upwind side of the post to prevent tearing, and some wooden slats and zip ties may go a lot further than metal nails or staples. Using hardware too small for the job is a common fencing mistake. Zip ties would also help with taking the fence down each spring to be stored for the next winter. Because plastic degrades so quickly in the sun, storing plastic snow fencing during the warmer months will help it last longer.
A wooden, permanent fence would follow much of these same protocols such as amount of open versus solid space, measurements, and stability. Wooden slats can be horizontal or vertical. Some highway departments use very large triangle-shaped snow fences that are semi-portable, but they may be overkill for your homesteading needs.
When installing fence posts and our snow fence, you will need to know which direction the prevailing wind comes from for your area during winter. While the wind differs with the weather, most areas have a direction from which the wind most commonly comes, although it may change with the seasons. How to tell what direction your prevailing wind comes from? Well, looking at a few young trees that weren’t staked may give a clue. Otherwise, you could ask your local extension office or consult data from weather stations.
Snow fences have been proven to reduce the cost of road maintenance including snow removal. They are also very effective in the prevention of auto accidents and deaths because the roadways are clearer. One study found that the cost of snow removal for highways was 100 times that of the cost of putting up a snow fence. That doesn’t even factor in the wear-and-tear that sanding and salting does to a road let alone the cost, financial, and emotional effects of auto accidents.
While you can make a multi- purpose fence that acts as a snow fence, the most effective snow fence does follow the before-stated guidelines. Whether to protect roadways or to gather extra snow for future water use, a snow fence is a very effective tool in directing the deposit of snowfall.
Resources
Vanhoenacker, M. (2013, August 1). What’s That Thing: Roadside Fence Edition. Retrieved April
14, 2020, from Slate: slate.com/ culture/2013/08/snow-fences-how- do-they-work-what-are-they-where- did-they-come-from-photos.html
Wisniewski, P. (n.d.). Living snow fence . Retrieved April 14, 2020, from State of Wisconsin Department of Transportation: wisconsindot. gov/Pages/doing-bus/local-gov/ hwy-mnt/winter-maintenance/ living-snow-fence.aspx
Do you live in an area where a snow fence is needed? What type do you use? We would love to hear from you in the comments below.
Originally published in the November/December 2020 issue of Countryside and Small Stock Journal.