Officials say the bridge that carries Interstate 43 over the Fox River in Green Bay will remain closed indefinitely after a concrete support pier settled by more than 2 feet.
The Leo Frigo Memorial Bridge was closed early Wednesday when a long, deep dip was discovered in the pavement about 5 a.m.
Gov. Scott Walker says the state will fix the bridge, emphasizing its importance to northeastern Wisconsin's economy.
State Transportation Secretary Mark Gottlieb said the bridge is not in danger of collapsing.
"We believe that the sag in the bridge duct was caused by the settlement of one of the bridge piers that's on land, obviously on the east approach of the bridge. The pier settled a little over 2 feet," said Gottlieb.
But Kim Rudat, the DOT's Northeast Region spokesman, said the closure could last months or even a year.
Press-Gazette Media report the bridge, built in 1981, carries about 40,000 vehicles a day.