620 ILCS 45/18
The tax rate for the payment of the principal of and interest on such bonds shall be in addition to the maximum rate now or hereafter authorized to be levied and extended for general county purposes or the general corporate purposes of the respective taxing district, and shall be in addition to the rates extended for any and all taxes now or hereafter authorized or permitted to be levied or extended for county purposes or corporate purposes of the respective taxing districts, in excess of the maximum rate for general county purposes now or hereafter permitted by law; and in excess of the maximum rate for general corporate purposes for the respective taxing districts now or hereafter permitted by law. Such tax shall not be subject to any limitation as to amount or rate except the constitutional limitation.
620 ILCS 45/18