7-13-4205. Determination of rental charge. (1) The total revenue to be collected from all of the above sources in a given year shall be provided for by the council in such a manner as to provide funds for the payment of all bond issues and interest thereon, as well as for all necessary expenses of the operation, maintenance, and repair of any such sewer system.

(2) For the purpose of making such rental charges equitable, property benefited thereby may be classified, taking into consideration the volume and character of sewage or waste and the nature of the use made of such sewage facilities.