Mich. Comp. Laws § 125.472

Sec. 72. Water supply. Every dwelling not exempted in section 7 of this act shall have within each apartment or family unit at least 1 approved sink with running water furnished in sufficient quantity at all times. The owner shall provide proper and suitable tanks, pumps or other appliances to receive and to distribute an adequate and sufficient supply of such water at each floor in the said dwelling at all times of the year, during all hours of the day and night. But a failure in the general supply of city water shall not be construed to be a failure on the part of such owner, provided proper and suitable appliances to receive and distribute such water have been provided in said dwelling.