(Lander, Wyo.) – New variable speed limit signs are now in operation on Wyoming Highway 28 over South Pass between Lander and Farson, according to the Wyoming Department of Transportation. The signs will allow WYDOT to drop the speed limit in 5 mph increments to as low as 30 mph when weather and road conditions make it necessary on a 34-mile section of the highway known for severe wind and surface conditions as well as heavy truck traffic.
The signs’ advanced technology allows WYDOT’s Transportation Management Center in Cheyenne to tailor the speed limit to match road conditions on highway sections as short as two miles in length.
The posted speed limit can be changed almost immediately after a reduction is recommended by WYDOT maintenance personnel or Highway Patrol troopers in the South Pass area.
“This is really going to help the traveling public and our maintenance guys up there,” said Don Detimore, WYDOT’s area maintenance supervisor in Lander. “Reducing speeds will help tremendously in preventing road closures due to crashes that can be avoided if drivers just slow down for conditions.”
The South Pass section is the fifth Wyoming highway section now served by variable speed limit technology. The other four sections are on I-80, where 128 miles are equipped with variable signs.
The first signs were activated along the Elk Mountain-Arlington section of I-80 during the winter of 2008-09. The additional sections were added after statistics from the first two winters using the variable signs showed they provided a positive return on investment in terms of fewer crashes and road closures.
The number of wintertime crashes on the Elk Mountain-Arlington section decreased two consecutive years, with half as many crashes occurring during the 2009-10 winter season, compared to same period of 2007-08, the winter before the signs were installed. The number of highway closures on the section dropped 36 percent.
“I know on I-80 people do slow down when the signs tell them to,” Detimore said. “The results there have been fantastic, and I think we’ll see the same improvements up here.”
Long-term statistics show unsafe speed is a factor in more than 70 percent of wintertime crashes in Wyoming. WYDOT is using the variable speed limits and its “Ice and snow? – Take it slow!” information campaign to counter that problem.
Decisions about where to install variable speed limit signs are based on traffic volumes, crash histories and frequency of severe weather on particular highway sections.