Md. Code, Public Utilities § 25–203

(a) To impose a benefit charge for the construction of a water supply or sewer system, the Commission shall classify each property that abuts on a street, road, lane, alley, right–of–way, or easement in which a water main or sewer line is to be laid as:

(1) agricultural;

(2) industrial or business;

(3) institutional;

(4) multi–unit business;

(5) multi–unit residential;

(6) residential subdivision; or

(7) small acreage.

(b) The classification of a property by the Commission is final, subject only to revision:

(1) at a hearing under § 25–204(a) of this subtitle; or

(2) by the Commission if the use of the property changes.