CHEYENNE — Nearly 900,000 people travel over Wyoming’s 3,101 bridges every day. They are probably unaware that those bridges may be structurally deficient.
A new report says more than 13 percent of Wyoming bridges are in that category.
Yet the rating doesn’t mean any bridge in the state is in imminent danger of collapse, state and local bridge officials say.
Transportation for America, a coalition of government, business and union officials that analyzes Federal Highway Administration data, ranked Wyoming’s bridges 12th worst in the nation in its 2013 survey.
Pennsylvania has the worst bridges while Florida was ranked as having the best.
More than half the Wyoming bridges labeled as deficient are state-owned while the rest are owned by local governments.
Most of the subpar bridges have problems with their decks, according to a report from the Wyoming Department of Transportation.
Keith Fulton, director of the department’s bridge division, said the decks develop “spall” or mini potholes.
“A lot of these have had a concrete overlay in the past and it becomes loose,” he said.
Overall, Fulton said, the state is holding steady on bridge repairs.
Carbon County has a few bridges with a low 2 rating.
Leo Chapman, chairman of the Carbon County commissioners, said the counties’ share of money from the new 10-cent fuel tax increase is earmarked to help take care of infrastructure problems like bridges as well as roads.
Two of the bridges with a low rating are on the Medicine Bow River and will be replaced, he said.
The county also has replaced bridges at Battle Creek and Savery.
“So we’ve been busily replacing them as time goes along. But money is always an issue,” Chapman said Wednesday.
The county also replaced a lot of bridges with box culverts and those bridges are no longer on the list.
The problem with the box culverts, he said, is that the beavers keep building their dams near a culvert where the stream narrows.
“The beaver dams load up the water against the side of the road, which is very dangerous to wash out a road,” he said.
“We go in with an excavator and pull them out and make the beaver mad. And the beaver is back again the next day.”
Mike Haigler, superintendent of the Natrona County Road and Bridge Department, said Wednesday that none of the Natrona County bridges on the list are near failure.
If the bridges were near collapse, they would be closed, he said.
“We’re replacing three bridges, one below Alcova Dam, one in Powder River and one on Bates Creek,” he said.
WYDOT policy is to inspect every bridge in the state at least once every two years and more frequently if needed.
The National Bridge Inspection Standards define the structurally deficient classification as “a reminder that the bridge may need further analysis that may result in load posting, recommended maintenance or rehabilitation strategies, structure replacement or closure.”
“The fact that a bridge is structurally deficient does not imply that it is likely to collapse or that it is unsafe,” the national standards say. “Rather, maintenance and rehabilitation of various components are necessary to restore its condition.”
To remain open to traffic, structurally deficient bridges are often posted with reduced weight limits that restrict the gross weight of vehicles using the bridges, according to the national standards.