To make sure they do the job right without creating more problems, they must be properly placed. Snow fences are just one of the ways to control drifting snow. Most snow blows through a good snow fence. Downwind of the fence, the wind slows and drops the snow. The better the snow fence, the more snow it takes from the blizzard.
Research shows that the best snow fences are about half solid and half openings.
We say that's 50 percent porous, it lets the blizzard through, but still slows the wind. Wyoming research shows that fences with 50 percent openings form drift lengths up to 25 to 30 times the fence height. If the distance between the fence and road to be protected is less than 30 times the fence height, then the snow drift may reach the road. That can make a drift problem worse, instead of eliminating it. For best results, keep a 4 ft. snow fence back at least 75 ft. and preferably 120 ft. from the road or driveway you want to protect.