(a) In this section, 'individual sewerage system' means a privately owned system of sewers, piping and treatment tanks or other facilities that: (1) Serves only a single lot for the disposal of sewage; and (2) Discharges to the surface waters of the State. (b) Except as provided in subsection (c) of this section, a person may not install an individual sewerage system in the State. (c) Subject to the Department’s approval, a person may install an individual sewerage system in the State for residential use if an existing on–site sewage disposal system fails and cannot be repaired or replaced by any means.
Maryland Legal Code