The revenues derived from the city's furnishing of water, light, electric, gas or other similar utility service shall be applied as follows:
(1) to the purposes of the respective departments under the direction of which the utility service is provided;
(2) for the reduction of debt related to the provision of the service provided under paragraph (1); and
(3) to another city department that provides labor or materials for the maintenance and repair of property or facilities relating to the city's provision of a utility service.