Mich. Comp. Laws § 235.7

Sec. 7. On the completion by the highway commissioner of any drain constructed under the provisions of this act, it shall be the duty of said highway commissioner to file in the office of the county drain commissioner a detailed report of the construction of such drain, giving the date of construction, the termini and general course thereof, together with a copy of the deed by which the right of way therefor was secured. Nothing in the provisions of the preceding sections shall be construed as giving to highway commissioners power to lay out and construct drains having any other purpose than the drainage of highways.