20 ILCS 3805/23a
The Authority may create and establish one or more special funds (herein referred to as "debt service reserve funds"), and shall pay into each such debt service reserve fund (a) any moneys appropriated and made available by the State for the purpose of such fund (except that no such State moneys shall be so paid with respect to such fund for notes or bonds a major portion of the proceeds of which are used to provide housing related commercial facilities), (b) any proceeds of sale of notes or bonds to the extent provided in the resolution or resolutions of the Authority authorizing the issuance thereof, and (c) any other moneys which may be available to the Authority for the purpose of such fund from any other source or sources. All moneys held in any debt service reserve fund, except as hereinafter provided, shall be used, as required, solely for the payment of the principal of bonds or notes secured in whole or in part by such fund or of the sinking fund payments with respect to such bonds or notes, the purchase or redemption of such bonds or notes, the payment of interest on such bonds or notes or the payment of any redemption premium required to be paid when such bonds or notes are redeemed prior to maturity. Moneys in such fund shall not be withdrawn therefrom at any time in such amount as would reduce the amount of such fund to less than the minimum debt service reserve requirement established for such fund by resolution of the Authority, except for the purpose of making, with respect to bonds or notes secured in whole or in part by such fund, payment when due, of principal, interest, redemption premiums and the sinking fund payments with respect to such bonds or notes for the payment of which other moneys of the Authority are not available. Any income or interest earned by, or increment to, any debt service reserve fund due to the investment thereof may be transferred by the Authority to other funds or accounts of the Authority to the extent it does not reduce the amount of the debt service reserve fund below the minimum debt service reserve fund requirement for such fund, as may be allowed by the resolution of the Authority authorizing the issuance of its bonds and notes.
The Authority shall not at any time issue bonds or notes, secured in whole or in part by a debt service reserve fund, if upon the issuance of such bonds or notes, the amount in such debt service reserve fund will be less than any minimum debt service reserve fund requirement for such fund, unless the Authority, at the time of issuance of such bonds or notes shall deposit in such fund from the proceeds of the bonds or notes to be issued, or from other sources an amount which together with the amount then in such fund will not be less than any minimum debt service reserve fund requirement for such fund.
In computing the amount of any debt service reserve fund for the purpose of this Section, securities in which all or a portion of such fund shall be invested shall be valued either (i) at par, or if purchased at less than par, at their cost to the Authority or (ii) as provided in the resolution authorizing the issuance of the bonds or notes which are to be secured by the fund.
20 ILCS 3805/23a