Effects of Snow Fences on Crashes and Road Closures: A 34-Year Study on Wyoming Interstate-80

This study evaluates the effectiveness of snow fences in reducing crashes and road closures on an 80.4 km remote rural section of Interstate Highway 80 (I-80) in southeastern Wyoming, and summarizes results from a detailed study to identify the need for additional safety improvements on this highway (Tabler 2006). No snow fences were in place when this section of I-80 was first opened to traffic in 1970, but serious snow drifting problems necessitated a large-scale snow fencing program from 1971 to 1990. The proportion of road protected by snow fences has increased to a present level of 73%, consisting of 69.7 kilometers of snow fence ranging in height from 1.8- to 4.3 m and constructed at a cost of $1,910,000. Total crash rates for October through April have declined in proportion to the percent of road protected by snow fences at the rate of approximately 18 crashes for every 10 % increase in snow fence protection. This decline is equivalent to a 70% reduction in areas protected by snow fences, and is attributable to the elimination of snowdrifts, improved visibility in blowing snow, and reduced road ice. At the 2003