Mich. Comp. Laws § 333.12752
Public sanitary sewer systems are essential to the health, safety, and welfare of the people of the state. Septic tank disposal systems are subject to failure due to soil conditions or other reasons. Failure or potential failure of septic tank disposal systems poses a threat to the public health, safety, and welfare; presents a potential for ill health, transmission of disease, mortality, and economic blight; and constitutes a threat to the quality of surface and subsurface waters of this state. The connection to available public sanitary sewer systems at the earliest, reasonable date is a matter for the protection of the public health, safety, and welfare and necessary in the public interest which is declared as a matter of legislative determination.
MCL 333.12752