Michigan Compiled Laws, Chapter 280. Drain Code of 1956 § 280.485

Sec. 485. When 2 or more public corporations, constituting as a whole contiguous territory, are served by 1 or more county drains, and it shall become necessary for the public health to supplement such existing drain or drains by constructing 1 or more relief drains, which may consist of new drains and branches and connections thereto or extensions, enlargements, branches, connections or improvements described in section 482  1 to existing drains, or any combination thereof, then the entire project may be constructed and financed as a whole under the provisions of this chapter and the word “drain” shall be deemed to include such a project.