An average of 26,300 vehicles per day drive across the small bridge on Main Street in East Peoria that crosses over Farm Creek. Those six lanes of traffic cross one of 166 bridges in the Tri-County Area that are “structurally deficient,” according to the Illinois Department of Transportation.
A bridge is considered structurally deficient if one of its main components is in poor condition and repairs are needed. Components include the deck, the part of the bridge people drive on; the superstructure, which supports the deck; or the substructure, the foundation of the bridge.
Even if a bridge is classified as structurally deficient, it does not mean it is unsafe, said Jessie Decker, an IDOT spokeswoman.
“IDOT has a thorough inspection program and verifies all bridges have the necessary strength to safely carry traffic,” she said in an email. “Although uncommon, a bridge will be closed if necessary to ensure the safety of the traveling public.”
Typical issues that come up during inspections of bridges can include the corrosion of steel and cracking and deterioration of concrete, according to Decker.
Omer Osman, acting secretary for IDOT, told the House Appropriations-Capital Committee at a recent hearing that $13 billion to $15 billion is needed for maintenance on the state’s roads and bridges. Of this money, $5 billion to $6 billion would go to bridges.
“Our infrastructure continues to deteriorate faster than we can keep up with it,” Osman said at the hearing.
About 8.6 percent of the bridges in Illinois are classified as structurally deficient. In Peoria County it's nearly 25 percent. Tazewell County has about 15 percent of bridges with the label, and it's 11 percent in Woodford County.
The number of structurally deficient bridges in Illinois spurred U.S. Sens. Dick Durbin and Tammy Duckworth, both Illinois Democrats, to write a letter urging the Federal Highway Administration to release $475 million in new federal funding for risk-based bridge repair and replacement. Some $24.3 million of that was released for Illinois bridges last week.
Illinois identified 2,642 bridges that need repairs. According to the senators’ press release, the state estimates the fixes will cost almost $10 billion.
Both chambers in the Illinois General Assembly have been holding hearings on what to include in a proposed capital bill that would provide billions of dollars for construction and repair projects throughout the state. Illinois has not had a capital bill in 10 years.
State Rep. Tim Butler, R-Springfield, said money for bridges are a vital part of the discussions.
“The bridge stock that we have in Illinois is aging rapidly,” said Butler, who also represents a portion of Tazewell County including the southeast part of Pekin. “A lot of bridges are reaching their useful lifespan. ... I do think we’re going to put a big emphasis on replacing bridges and repairing bridges to make sure they’re safe.”
That said, the wide-ranging list of improvement projects needed in Illinois means a capital bill won’t get anywhere close to funding everything, Butler said.
“We have to continue to prioritize and do the best we can to come up with a funding model that’s sustainable,” he said.
Of the nearly 27,000 bridges in Illinois, IDOT inspects about 7,800 of them. The rest are owned, maintained and inspected by local governments and agencies.
Decker said the amount of traffic on the bridge, the age of the structures, and varying amounts of money local agencies have to make repairs all contribute to bridge conditions. The type of inspection and how often they happen depend on the type of bridge and its condition, she said.
Illinois has the fifth-highest number of structurally deficient bridges in the country, according to the American Society of Civil Engineers.
The Murray Baker Bridge carries Interstate 74 over the Illinois River, and, at 66,200 vehicles a day on average, represents the structure carrying the most traffic each day. It's slated for deck replacement beginning in 2020.
That's at the high end. A host of other bridges carry 1,000 vehicles or fewer a day, some as few as 50, according to IDOT estimates.
The term “structurally deficient” itself sounds bad, but it represents an official federal designation that helps define whether it's eligible for funding. Lives aren't necessarily in danger when crossing it, said Brian Davis, an engineer with the Sangamon County Highway Department.
If that were the case, a bridge would be closed or its weight limit reduced until repairs could be made. The former happened last summer with the bridge on Illinois Route 8 that crossed over the BNSF railroad tracks along a common route to Wildlife Prairie Park. It was closed to the average 2,600 vehicles a day until temporary repairs could be made.