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Snowfall not all bad for county roads
Apr 10, 2013 - By Eric Blom, Staff Writer
Snowfall Monday and Tuesday brought a lot of work for Fremont County's Transportation Department, but the moisture will help local roads as well.
"This moisture is a real good thing," transportation superintendent Dave Pendleton said. "It's kind of a pain for people to get around, but it sure helps the countryside out. This moisture represents moisture we couldn't haul out to every road, so we're real hesitant about taking the snow off of gravel or dirt roads."
He made clear that roads crews will plow those roads if the snow is too deep for drivers to travel on, but he said the moisture helps dirt and gravel in unpaved roads stick together.
A lack of moisture causes cohesive materials in roads to turn to powder and no longer work, Pendleton said. In turn, the vehicles that pound the road turn it soft.
The lack of rain in the spring and summer of 2012 brought about several such "blow outs," Pendleton said.
A notable one was on Shoshone Lake Road, about six miles west of Lander.
"That red dirt turns into powder," Pendleton said. "You may be driving into 6 inches or a foot of powder."
Moisture prevents blow outs and allows treatments like magnesium chloride to soak deep into the road. The compound suppresses dust and stabilizes the road.
"You have to have moisture in the materials or else it's a surface treatment and it comes apart in short order," Pendleton said. "It breaks the surface tension and allows the magnesium chloride to be drawn down into the material."
The transportation superintendent said moisture also helps repair "frost heaves."
Frost heaves occur when underground water encounters the frozen layer of ground near the surface of the earth during winter. The groundwater freezes as it encounters the cold dirt and expands.
More water migrates up because of the capillary action and freezes, growing the pocket of ice. The frozen water creates a lens that grows upward and can weaken a road above it.
"You end up with soft spots in a gravel road," Pendleton said. "After we get some moisture, it tends to help and go away."
The snow did make a lot of work for road crews for a few days at least.
Pendleton said every piece of equipment his department has was out plowing and sanding Monday and Tuesday.
"If we think there's going to be a snow storm we put the plows on (the department's trucks) and load the sanders up with sand and stick them in the barn," he said.
Pendleton said four trucks in the Riverton area and the four stationed in Lander were plowing and sanding by noon Monday, and the department's 10 motor graders joined them to clear snow.
They were back out at 3 a.m. or 4 a.m. Tuesday to clear roads for morning traffic and worked through the afternoon to plow them again for people going home.
County transportation is responsible for 950 miles of roadways and additional miles of bus routes over roads the county does not maintain.
"I think our guys do a very good job of getting the roads cleared off and getting them cleared off sooner," Pendleton said.