Inspectors this week are completing an annual examination of the Interstate 80 bridges that state officials say is done to assure they are safe to drive on, despite the need for repairs.
The bridges – one eastbound and one westbound – over the Des Plaines River have been described as a poster child for the state’s infrastructure problems, and their replacement is a priority in Gov. J.B. Pritzker’s $41.5 million “Rebuild Illinois” plan.
The Illinois Department of Transportation plans to replace the bridges, but does not yet have the funding.
Bridge inspection reports from spring 2018 deem them, in a structural evaluation of both the eastbound and westbound bridges, as "intolerable," while listing the westbound bridge as "high priority for replacement" and the eastbound bridge as "high priority for correction."
"When these terms show up, it doesn't necessarily mean the bridge is unsafe," said Carl Puzey, bureau chief for bridges and structures at IDOT, adding "it's understandable these terms get attention."
Puzey said they get attention at IDOT, too.
“But the first step is to assure that the bridge can carry traffic,” he said.
The bridges are safe, IDOT said. No weight limits have been placed on the bridges.
Illinois bridges basically have three levels of operation, IDOT officials said: Open without restrictions, open with weight limits and closed.
Crews this week have been inspecting the westbound bridge, a project scheduled earlier this month but delayed by rain. The eastbound bridge was inspected from May 5 to 11.
The state returns every three months to inspect and monitor the bridges. However, the spring inspection is the major review that leads to a report on bridge conditions posted on the IDOT website.
“So far, we haven’t identified anything in these bridges that requires immediate repair,” said Sarah Wilson, bridge maintenance engineer for IDOT.
IDOT, however, has begun a $5 million repair project that is likely to continue into the 2020 construction season. Replacement expansion bearings
are being manufactured now, and crews will be at the bridges in coming weeks to replace 1,000 expansion bearings.
A fraction of the bearings were found to have been bad, Wilson said. But because of the age of the bridges, the decision was made to replace all the expansion bearings.
The pair was built in 1965.
The age of the bridges contributed to their poor ratings and the need for replacement.
The westbound bridge had a sufficiency rating of 6 out of 100. The eastbound bridge had a sufficiency rating of 7.4.
“Sufficiency rating is a much larger look at the bridge,” Wilson said, adding that it’s not a prediction of the chances that the bridges will stay standing.
She said the bridges have no shoulders, a result of the 1965 construction design and not one that would be used today.
“That also affects that 1 to 100 rating.” Wilson said.
It is unclear whether funding will be available for replacement of the bridges by the time the state Legislature goes into its final day of the spring session on Friday.
No capital plan, including the governor’s, had been presented to the legislature for a vote as of Thursday afternoon.
The Pritzker “Rebuild Illinois” plan calls for replacement of the bridges as part of improvements on a stretch of I-80 between Route 30 in New Lenox and Ridge Road in Minooka.