Mich. Comp. Laws § 254.101

Sec. 1. The bridge across Portage lake extending from Dakotah street in the village of Houghton to Front street in the city of Hancock, Houghton county, is declared a part of the state trunk line highway system, and the improvement, repair and maintenance thereof shall be under the supervision and control of the state highway commissioner. The county of Houghton is hereby relieved of all duties, powers and obligations with respect to the future repair, maintenance and improvement of said bridge.