605 ILCS 5/6-515
The highway commissioner and the road district clerk of any road district, without submitting the question to the electors thereof for approval, may authorize by resolution the issuance of refunding bonds (1) to refund its bonds prior to their maturity; (2) to refund its unpaid matured bonds; (3) to refund matured coupons evidencing interest upon its unpaid bonds; (4) to refund interest at the coupon rate upon its unpaid matured bonds that has accrued since the maturity of those bonds; and (5) to refund its bonds which by their terms are subject to redemption before maturity.
The refunding bonds may be made registerable as to principal and may bear interest at a rate not to exceed the maximum rate authorized by the Bond Authorization Act, as amended at the time of the making of the contract, payable at such time and place as may be provided in the bond resolution.
With respect to instruments for the payment of money issued under this Section either before, on, or after the effective date of this amendatory Act of 1989, it is and always has been the intention of the General Assembly (i) that the Omnibus Bond Acts are and always have been supplementary grants of power to issue instruments in accordance with the Omnibus Bond Acts, regardless of any provision of this Act that may appear to be or to have been more restrictive than those Acts, (ii) that the provisions of this Section are not a limitation on the supplementary authority granted by the Omnibus Bond Acts, and (iii) that instruments issued under this Section within the supplementary authority granted by the Omnibus Bond Acts are not invalid because of any provision of this Act that may appear to be or to have been more restrictive than those Acts.
605 ILCS 5/6-515