Mich. Comp. Laws § 325.1003b

Sec. 3b. (1) The department may do 1 or more of the following: (a) Conduct a capacity assessment at a community supply, a nontransient noncommunity water supply, or a public water supply applying to the department for assistance under part 54 of the natural resources and environmental protection act, 1994 PA 451, MCL 324.5401 to 324.5418. (b) Conduct a source water assessment at a public water supply. (c) Enter the facilities and business offices used in the operation of a public water supply. (2) Public water supplies shall make available to the department records needed to conduct a capacity assessment or source water assessment. The department may request information in writing or during on-site visits to conduct capacity assessments or source water assessments.