The bridge on Oak Grove Road just off Helmsburg Road is closed until further notice because of a split in its support structure.
Crews doing ditching in the area on June 2 noticed cracked asphalt and a dip in the bridge, and investigated, which is how the split in the timber was discovered, said Brown County Highway Superintendent Mike Magner.
There is no posted weight limit, he said. Manufactured by American Timber Bridge, the bridge was installed in 1989 and is rated for loads that are legal on county roads, Magner said.
It was last inspected between October and November 2015 during the annual county bridge inspection, he said.
The county is waiting on a representative from the bridge manufacturer to evaluate the damage, Magner said. It will not be possible to estimate how long repairs will take until the evaluation is done, he said.
The county will have to determine how to pay for the unscheduled repair.