Mich. Comp. Laws § 247.651f

Sec. 1f. The obligation of any city under 30,000 population which prior to July 1, 1957 entered into a contract with the state highway department pursuant to the provisions of Act No. 19 of the Public Acts of 1919, as amended, for the construction of state trunkline highways, which highways have been taken over as part of the interstate and defense highway system, is hereby canceled and the city is relieved of any obligation remaining under the contract. The state highway department shall assume the obligation still outstanding under the terms of such a contract upon the effective date of this amendatory act.