(a)   The Department of Public Service established by the Charter shall be organized in two divisions:
      (1)   Division of Streets, Sewers, Public Lands and Buildings and Equipment Maintenance;
      (2)   Division of Sewage Treatment.
   (b)   Each division of the Department of Public Service shall be under the immediate supervision of a division superintendent. Nothing in this section shall preclude the assignment of one person to supervise several divisions concurrently.