(70 ILCS 3010/19a) (from Ch. 42, par. 319.19a)
    Sec. 19a. Sufficient revenue derived from the operation of such a sewerage system, improvement, or extension shall be set aside as collected, and deposited in a special fund of the sanitary district. It shall be used only for the purpose of paying the cost of operating and maintaining the sewerage system, improvement, or extension, providing an adequate depreciation fund, and paying the principal and interest on the bonds issued by the sanitary district under Sections 13 to 19a, inclusive, for the purpose of constructing or acquiring the system, improvement, or extension.
(Source: P.A. 83-333.)