Md. Code, Natural Resources § 3-127

(a) Except as otherwise provided by this subtitle, the Service may adopt, formulate, revise, and enforce rules and regulations necessary for the regulation of its internal affairs and for the use and operation of its projects, and of any other laws the administration of which is vested in the Service. A rule or regulation concerning the use or operation of a project may not conflict with any rule, regulation, permit, or hauler certificate of the Department of the Environment. The Service may limit or regulate water supply or liquid waste service, refuse collection, disposal service, and storm and surface water drainage service, in any area or to any premises served by Service projects, as the exigencies of the occasion and the protection of its systems require. The Service may adopt lawful and reasonable regulations it considers necessary for the public’s health and safety, comfort, and convenience in the construction, operation, maintenance, expansion, relocation, replacement, renovation, and repair of its water supply, wastewater purification, solid waste disposal, and energy projects.

(b) Rules and regulations shall be approved by the Board and adopted under the provisions of the Administrative Procedure Act, except when necessary for the immediate preservation of the public health and safety and except for emergency provisions required to protect Service projects.

(c) Any regulation adopted by the Service under this section has the effect of law.