GREEN BAY, Wis. (WFRV) - The investigation into the cause of the sagging roadway on the Leo Frigo Memorial Bridge in Green Bay is ongoing. However, Wisconsin Department of Transportation officials revealed Wednesday, it appears one of the concrete support piers settled - causing the issue.
On a normal day, the Leo Frigo Bridge on I-43 carries 40,000 vehicles across the Fox River. Right now, the highway is completely empty - closed after a flurry of 9-1-1 calls from drivers just before 5 a.m. - who discovered a 400-foot long section of road had sunk some 20 inches.
"About halfway up on the eastbound side that bridge is sagging in the center," one man reported when calling Brown County's 9-1-1 center.
"We believe the sagging in the bridge deck was caused by the settling of one of the bridge piers," said Mark Gottlieb, secretary of the Wisconsin Department of Transportation.
At a news conference Wednesday afternoon, with Governor Walker looking on, transportation officials explained their investigation so far shows, one concrete support pier shifted quickly.
"We're thinking between 9 last night and 4:45 a.m. when it was reported," said Dale Weber, bridge supervisor for WisDOT's Northeast Region.
As this picture shows, it settled roughly 2 feet. The shifting caused the bridge deck across all four lanes to dip. Now the question engineers are trying to answer is what caused the movement in the first place.
"We're taking soil information near the piers to see what's going on below so we can determine what happened there," Weber said.
Engineers plan to monitor this pier for future movement and check other piers for potential problems. However, this work will take time:
"This is a significant incident, going to take us some time to investigate and ultimately solve," said Sec. Gottlieb.
In addition, the bridge still needs to be repaired. And at this early stage in the investigation, no one is able to be to give a firm timeline on when it could possibly reopen.
"Could be a month, could be a year," said Kim Rudat, Northeast Region communications manager. "Folks this is brand new - it just happened this morning - we're trying to be careful."
Thursday the DOT plans to hold another briefing in the afternoon to update the media on the progress of their investigation.