It shall be the duty of any person, firm or corporation who are the owners and proprietors of any canal, ditch or other conduit constructed for the conveyance of water, or other opening through or across a public highway or street, which are used principally for power purposes, to restore such highway to passable condition, and to build, rebuild, maintain and keep in repair at such proprietor’s or owner’s expense, a good and sufficient bridge or viaduct over and across the same, of the size and kind required by law of the highway authorities in charge of such highway or bridge. If such bridge be located within the corporate limits of a city of the first, second or third class it shall be built, rebuilt, constructed and repaired under the supervision of the city council or board of commissioners of said city, and when required to be rebuilt shall be built according to plans and specifications prepared under their supervision.

If located upon a county road or on a township road if the county engineer’s estimated cost exceeds $600, such building or rebuilding shall be according to plans and specifications approved by the board of county commissioners and the county engineer. If located upon a township road, and the county engineer’s estimated cost does not exceed $600, then such bridge shall be built, rebuilt, maintained and repaired according to plans and specifications approved by the township board of highway commissioners, and by the county engineer.