Whenever any county has been authorized by the commissioner of natural resources to divert the channel of a navigable stream for the purpose of improving a county road and the board of commissioners of such county has by resolution ordered diversion of the navigable stream across private property so that the stream and the channel thereof when so diverted deprives the owner of the private property of access to the county road, the owner of the private property may grant to the county a perpetual easement for road purposes across that private property commencing at a point 50 feet distant from the relocated or diversion channel, thence crossing the relocated or diversion channel and intersecting the county road so to be improved; and the road easement shall extend for a distance of two rods on each side of the centerline thereof and be and remain a public road. The county shall forthwith establish and construct a highway upon the strip of land pursuant to law, build a suitable bridge, including approaches thereto, across the channel, and at public expense thenceforth maintain the road and bridge so established in a safe condition so as to afford the owner of the private property access to the improved county road.