Suamico - A quarter-mile of a southbound lane of U.S. 41 in northern Brown County was closed for 9½ hours Tuesday after a 5-foot by 3-foot sinkhole in the road developed in the morning.

The sinkhole opened about a half-mile south of Brown Road when soil infiltrated a concrete culvert pipe and the pavement above the pipe sank, according to the state Wisconsin Department of Transportation.

"It doesn't happen very often, but it obviously happens," said Kim Rudat, a DOT spokesperson.

The sinkhole opened at 8:30 a.m. and shut down the affected southbound lane until about 6 p.m.

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