Building effective Snow Fences Better than a good idea

on 04 January 2016

The outpouring of snow in that last ten years in various part of United States have been recording setting in certain places. These often come with loss of properties and life at times. Snow and ice removal and control costs over $2 billion annually in the US. Blowing and drifting snow causes impaired road conditions, reduced visibility, increased number of accidents and injuries, reduced road width, and increased need for plowing and deicing materials.

Although the idea of snow fencing is not necessarily a new one, but it’s not something as rampant as security fencing or other form of fencing. In actual sense, snow fences can save lives and reduce maintenance costs. Studies published by Strategic Highway Research Program (SHRP) of National Research Council in 1991 showed that Mechanical snow removal costs about 100 times more than trapping snow with fences.

On the other hand, to be effective, snow fences need to be designed and placed properly. Many studies have shown the old-fashioned fence of 4-ft. (1.4-m) picket fence to be an ineffective snow collector. These old fashioned designed are often placed in contact with the ground.

According to SHRP, to be very effective and economical, modern snow fence need only have a single row of tall fences instead of the multiple rows of shorter fences common with the old fashioned designs. Properly designed and placed, taller fences are dramatically more effective than the traditional low picket fence. New lightweight plastics now allow the construction of portable fences up to 8 ft. (2.4 m) tall. In terms of porosity, a modern snow fence with a porosity of 40% to 50% will likely be better.

Most of the effectiveness of snow fencing are in the designing. There is tendency for a snow fence projects to fail if the fences are improperly designed or placed. One common mistake identified in the SHRP report is the failure to design the fence for the capacity of snow it needs to hold over the season.

It is also important not to place the fence too close to the road as this could actually make snowdrift problems worse. Fences should be set back at least 35H from the road shoulder. The snow fences should be extended beyond protection limits to an angle of 300 on either side of the prevailing wind direction.

One of the most important work that has been done in encouraging the use of snow fencing is the Snow Fence Guide developed by SHRP. This guide cover everything maintenance personnel need to know in order to design and locate snow fences correctly. A free copy of the guide is available in the link below.