Md. Code, Public Utilities § 24–101

(a) (1) A person shall obtain a permit from the Commission before the person may engage in plumbing, waterworks, or sewer construction in a building or on private property in the sanitary district or areas of Prince George’s County that are not in the sanitary district.

(2) The person shall pay to the Commission a reasonable permit fee set by the Commission.

(b) Work performed under a permit authorized by this section shall:

(1) conform to the Commission’s regulations; and

(2) be subject to any inspection that the Commission considers necessary.