Va. Code Ann. § 15.2-634

The department of public utilities, if and when established, shall be under the supervision of a director of public utilities appointed by the county manager. The department shall be in charge of the construction, operation, maintenance and administration of public utilities, owned, operated and controlled by the county or any sanitary district of the county, including but not limited to water systems, sewer systems, sewage disposal systems, solid waste management, street lights and any other related functions not assigned to or administered by other departments. If the county has a division of fire and a fire chief under the provisions of § 15.2-633, then the division of fire shall not be under the department of public utilities.