6/20/2012
Reed Hollinshead
ITD Communication
208-334-8881
reed.hollinshead@itd.idaho.gov
Green "living snow fence" on U.S. 20 provides snow break, safety
ELMORE COUNTY - Drivers on U.S. 20 from Mountain Home to Fairfield will be seeing a brand new structure soon in this flat landscape dominated for years by sagebrush, barbwire fences, and, in the winter, snow drifts that create havoc with travelers.
In mid-May, crews from the Idaho Transportation Department's Mountain Home maintenance shed installed a 1,600-foot “living snow fence” along the highway, between mileposts 109 and 110, about 19 miles northeast of Mountain Home. The fence is actually a double row of trees planted on the north side of the road to provide a natural barrier to the snow that routinely drifted across the highway.
Click here for a picture of the fence being "built."
In the past five years, all but two of the 16 crashes recorded at that location were influenced by road surface conditions of snow, ice or slush, or by animals (wild and domestic) on the roadway.
Over the years, ITD found that this stretch of U.S. 20 required above-average expenditures in snow and ice removal and overall winter maintenance.
“Something had to be done because there were places like Sun Valley, a local community with a high volume of tourists in the winter months, that used U.S. 20 as the major travel route to their destination,” explained Dave Labar, Mountain Home maintenance foreman. This relatively flat and unprotected area allowed drifts to easily form on the raised roadway, increasing travel time and negatively impacting commerce within local communities.
In addition to high maintenance costs, the section of highway was chosen based on low visibility for drivers in winter and large right-of-way access.
“Because of terrain and cost effectiveness, a living snow fence was selected as the best solution to the problem," said District Maintenance Engineer Tom Points. “The fence uses trees or shrubs to catch or trap snow to keep it from depositing on the roadway. It is much cheaper to do this than it is to plow that same snow. It is also less visually intrusive than a standard plastic snow fence. “
The legwork began in earnest in November 2011, as the Mountain Home Air Force Base donated 155 cubic yards of organic natural compost to prep the living snow fence project site. The organic compost material will ensure the survival of the newly planted trees. The base also committed more than 200 yards of wood-chip mulch to aid in weed and moisture control for the project.
ITD’s crews, with assistance from an Idaho Department of Corrections (IDOC) inmate labor crew, planted 400 Rocky Mountain Juniper seedlings, chosen based on their hardiness, resistance to drought and insects, and adaptability to local soil conditions.
"According to Natural Resources Conservation Service who selected this species for us, they are of a moderate growth rate," said ITD Hammett maintenance foreman Carl Vaughn. "They have an average 20-year height of 12-15 feet and do well in the soil conditions we have on U.S. 20. The trees have a life span of 30-35 years baring bugs or fire damage."
“Living snow fences are more cost-effective than structural or temporary barriers,” said Points. The fence also provides other benefits beyond just snow control - like a a potential habitat for a variety of wildlife species.
Though the efforts and full impacts of this living snow fence will not be known for several years, it has the potential to affect commerce and safety, two of ITD's main goals, for generations. The economic impact of this project also aligns with the goals of the Idaho Governor's Office Project 60 initiatives.
The fence could not have been built without the combined efforts of ITD, IDOC, USDA Natural Resource Conservation Service, University of Idaho, Mountain Home Air Force Base and Idaho Fish and Game.
“In a time of shrinking budgets and resources, demanding that we do more with less, finding frugal solutions is a necessity,” said District Engineer Dave Jones.
“Projects like these could not be accomplished without the assistance of outside organizations,” said Jones. “It is good to know that cooperative ventures exist that provide the public with a low-cost solution that still delivers a safe public highway.”