Mich. Comp. Laws § 462.227

Sec. 227. (1) Any street railway, or any railroad company, organized under the laws of this state, may own and operate, in connection with its railway lines, such number of steamboats, barges, or vessels, within or without this state, as its traffic of passengers or freight shall render necessary to make complete its different routes. (2) A railroad company shall operate such steamboats, barges, or vessels subject to such restrictions as are now imposed on other corporations and private individuals owning and operating steamboats, barges, and vessels.