Pier 22 is shown on the Leo Frigo Bridge on Thursday, Oct. 3, 2013. / H. Marc Larson/Press-Gazette Media
The Leo Frigo Memorial Bridge has dropped another half inch, about a week after a noticeable sag developed because of a 2-foot drop of a support column that officials said was caused by corrosion and buckling.
The additional drop, announced Friday by the state Department of Transportation, is the first movement detected on the bridge since the initial sag was reported early Sept. 25. The bridge was closed that morning. On Friday, officials said that they do not believe the bridge is at risk of collapse.
“It happened sometime between Tuesday and Thursday,” Kim Rudat, the department’s communications manager for the northeast region, said Friday about the additional sinking. “It was very slow.”
Wisconsin Department of Transportation officials said support towers will be built next to the bridge in the area around the sunken pier to stabilize the structure and protect workers.
“That will make sure that if it does sink any more it will isolate this section of the bridge from the rest of the bridge,” Rudat said.
Officials have not finalized a timeline for construction of those supports.
The preliminary estimate to fix the bridge is $50 million, though that number is subject to change, transportation officials said Friday. The department is in the early phases of developing a plan to fix the bridge and no estimate has been given on when the structure may reopen.
Transportation officials said the preliminary investigation indicates the pier sank due to corrosion and buckling of the 100-foot-long steel supports dug deep into the ground under the pier. The corrosion appears to be from a combination of water and the composition of the soil in that area of the bridge.
A number of other piers around the one in question — Pier 22 — also showed signs of corrosion, officials said during a press conference on Thursday.
In other developments Friday, the Federal Highway Administration said the bridge is eligible for emergency funding. Wisconsin Gov. Scott Walker requested those funds by declaring a transportation emergency in Brown County last week.
“The federal funds will cover 100 percent of emergency repairs within 180 days following the bridge's closure,” a press release from the Wisconsin Department of Transportation stated. “After the first 180 days, emergency repairs and all permanent repairs will be at a 90 percent federal share.”
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