65 ILCS 5/8-7-4
All money received from the issuance of bonds as authorized in Section 8-7-2, or from any tax levied pursuant to the authority granted by Section 8-7-3, shall be set apart in the working cash fund by the municipal treasurer and shall be used only for the purposes and in the manner provided in this section. The fund and the money therein shall not be regarded as current assets available for appropriation and shall not be appropriated by the corporate authorities in the annual appropriation ordinance.
The corporate authorities may appropriate moneys to the working cash fund up to the maximum amount allowable in the fund, and the working cash fund may receive such appropriations and any other contributions.
In order to provide money with which to meet ordinary and necessary disbursements for salaries and other general and special corporate purposes, the fund may be transferred in whole or in part to the general or special corporate funds of the municipality, and so disbursed therefrom in anticipation of the collection of any taxes lawfully levied for general or special corporate purposes or, in anticipation of such taxes, as by law now or hereafter enacted or amended, imposed by the General Assembly of the State of Illinois to replace revenue lost by units of local government and school districts as a result of the abolition of ad valorem personal property taxes, pursuant to Article IX, Section 5(c) of the Constitution of the State of Illinois. Money so transferred to the general or special corporate funds shall be deemed to have been transferred in anticipation of the collection of that part of the taxes so levied or to be received which is in excess of the amount required to pay any tax anticipation warrants, and the interest thereon.
Taxes levied for general or special corporate purposes, when collected shall be applied first to the payment of tax anticipation warrants or notes and the interest thereon, and then to the reimbursement of the working cash fund.
Upon the receipt by the municipal treasurer of any taxes, in anticipation of the collection of which money in the working cash fund has been so transferred for disbursement, the fund shall be immediately reimbursed therefrom until the full amount so transferred has been retransferred to the fund. Unless the taxes so received and applied to the reimbursement of the working cash fund, prior to the first day of the eighth month following the month in which due and unpaid real property taxes by law begin to bear interest, are sufficient to effect a complete reimbursement of the fund for any money transferred therefrom in anticipation of the collection of taxes, the working cash fund shall be reimbursed for the amount of the deficiency therein from any other revenues accruing to the general corporate fund, and the corporate authorities shall provide for the immediate reimbursement of the amount of such a deficiency in its next annual appropriation ordinance.
Any municipality holding in its working cash fund money not immediately necessary for the purposes set forth in this Section may, by ordinance, use such money to invest in its own bonds issued by the municipality which represent the obligation of such municipality, or, may use such money to invest in bonds and other interest bearing obligations of the State of Illinois, or securities authorized for investment in "An Act relating to certain investments of public funds by public agencies," approved July 23, 1943, as heretofore or hereafter amended; provided, however, that no investment authorized by this Section 8-7-4 shall be made in bonds or interest bearing obligations which are in default or in bonds or interest bearing obligations for which accrued interest is due. All money realized by the municipality from the sale or redemption of the securities authorized for investment under this Section shall be placed in the working cash fund. Interest on the investments may also be placed in such fund, or, if so provided in the ordinance authorizing such investments, may be transferred in whole or in part to the general or special corporate funds of the municipality.
65 ILCS 5/8-7-4