Making Snow-Covered Roads Easier to Open
By using improved snow fences, the Alaska Department of Transportation (DOT) is making spring snow clearance faster and easier.
The Challenge
Located among barren, low-rolling hills, Alaska's Nome-Council highway has little natural protection from extreme winter weather. As a result, heavy snow accumulation closes the road from mid October until April, when maintenance crews dig it out.
Developing the Strategy
In 1990, the Alaska DOT decided to test snow fences that had been evaluated as part of the Strategic Highway Research Program (SHRP). They chose a 16-km (10-mi) stretch of the Nome-Council highway. "By reducing snow drifting and accumulation, we hoped to keep the road open later into the fall and reopen it earlier in the spring," says Jim Adams, maintenance and operations supervisor for Alaska DOT. "We also wanted to reduce the cost of opening the road each year."
Putting the Strategy to the Test
In 1993, prior to the onset of winter, Alaska DOT installed 1,500 m (5,000 ft) of the new snow fences along the Nome-Council highway. Each fence panel was 4.8 m (16 ft) long and 4.2 m (14 ft) high.
As the winter progressed, video cameras were used to record the snow accumulation along this stretch of road.
What They Learned
Video recordings taken over the following two winters provided proof of the effectiveness of the snow fences. Snow depth in areas protected by the fencing ranged from nothing to 1 m (3 ft), while the fences held back 2.4 to 4.2 m (8 to 14 ft) of snow. In contrast, sections of the highway without fence protection had a wall of snow about 3 m (10 ft) high.
The unprotected areas required 2 to 4 days to clear in the spring, while those with snow fences could be cleared in 2 hours, saving thousands of dollars in labor.
This performance was better than expected, and Alaska DOT is looking into expanding the use of these new snow fences on the highway.
The Benefits
- The fence-protected road sections stay open longer in the fall and can be cleared faster in the spring.
- Dollar savings are substantial due to reduced staff costs.
- The reduced snow accumulation means a safer working environment for road crews.
- Wear and tear on equipment is reduced.
