Nearly 11 percent of all bridges in the United States are deemed structurally deficient, according to a recent report by the national advocacy group, Transportation for America.
The report, released June 19, says that of the 607,380 bridges nationwide, roughly 67,000 are substandard by federal guidelines.
But despite the deficiencies, Americans still make roughly 260 billion trips them on a daily basis.
This report came nearly a month after the May 23 collapse of a bridge along Interstate 5 in Mount Vernon, Wash., and the Aug. 1, 2007, collapse of Minneapolis’ Interstate 35W bridge.
The Minneapolis collapse alone resulted in 13 fatalities. No deaths were reported in the Washington collapse.
The estimated federal cost of bridge repair and maintenance currently sits at $121 billion.
While Pennsylvania, and Oklahoma claimed the top spots in structural deficiency, at 24.5 and 22.6 percent, respectively, Nevada and Florida came in the bottom in the report, tying at having just 2.2 percent of deficient bridges.
Though Iowa saw a small drop in deficient bridges, the numbers remain high.
For Iowa Department of Transportation bridge-maintenance and inspection-engineer Scott Neubauer, this comes as no surprise.
“It’s where we’ve been for a while,” he said. “It is a major issue, there’s no question.”
But with counties in charge of ensuring the maintenance of their own bridges, he said, the numbers could only change if the counties do as well.
Though Iowa’s 21.2 percent figure is a 4.6 percent decrease since 2011, more than 5,000 of the state’s nearly 25,000 bridges scored a 4 or below on a scale of 10.
The average annual cost of the state bridges maintained by the Iowa Department of Transportation stands between $1.4 million and $1.6 million.
Because Iowa is sixth in the nation for the most number of bridges, the issue spreads throughout the state.
According to Transportation for America, a national transportation advocacy group, there are 25 deficient bridges within a 10-mile radius of Iowa City.
But, Assistant City Engineer Denny Gannon said, he believes the city’s bridges are in good shape.
With a federal requirement for bridges to be looked at every 24 months, he said, the city construction for these as needed.
“Iowa City’s been keeping up progressively,” he said. “We’re always replacing the bad.”
Gannon said bridges are built with three primary components: the surface to which people and vehicles cross, known as the “deck,” the “superstructure,” which supports the deck, and the “substructure,” which aids the superstructure.
The deficiency of a bridge is determined by rating the bridge based on these three structures, according to data from the Transportation for America. If a bridge receives a grade lower than a 4 out of 10, it is determined as structurally deficient.
Though Gannon was unsure as to the cost of maintenance to local bridges, he said the city handles repairs and construction on a by-need basis.
Des Moines chief design engineer Darwin Larson said of the 73 bridges in the Des Moines metropolitan area, 17 are classified as structurally deficient, or approximately 23 percent.
With comprehensive inspection currently underway, Larson said, he hopes this number will soon drop as the city tries to ensure two bridges get worked on every year. He estimated the cost per bridge to range from $2.4 million to $5.9 million.
Though the Transportation for America report said an average bridge age is 43 years with the designed lifespan of 50, with an estimate of one in four reaching the age of 65 in the next 10 years, Larson believes there are ways to elongate these numbers.
“It’s a pretty major rehabilitation to repair deterioration,” he said. “But it will help them last longer than 50 years.”
As part of the two-year inspection, Larson said they must report their numbers biannually to the National Inspection Program, which works in line with the Department of Transportation and the Federal Highway Association to discover any issues and determine a solution.
In Iowa’s second largest city, however, the situation appears more optimistic.
Cedar Rapids capital improvement project manager Doug Wilson said that of the 49 road bridges in the city, just three are classified as deficient, or roughly 6 percent.
With projects in the works to repair them in the upcoming years, Wilson said the City Council has been consistent with approving the work on bridges.
Ranging from $150,000 to $500,000, the budget for projects varies depending on the structure and its importance.
Despite national and state initiatives such as these programs, James Corless, the director of Transportation for America, is unhappy with the continued high number of dysfunctional bridges.
“We are letting a lot of our existing infrastructure deteriorate and kicking the can down the road in terms of maintenance and funding,” he wrote in an email.
But despite Iowa’s drop in deficient-bridge rating, Iowa City resident K. Lindsay Eaves is not impressed with the state’s numbers.
“Someone has obviously fallen down on the job,” she said. “It’s something that needs more attention.”