Section 70 ILCS 535/9 - Bridges(a) In addition to the power and authority heretofore conferred upon the Authority, the Authority, in its own name, shall have full power and authority: to acquire and thereafter operate and maintain any existing vehicular toll bridge across any waters which form a common boundary between any city within the territory of the Authority and any other city either within or without the State and to reconstruct, improve and repair such existing bridge; to construct, maintain and operate an additional vehicular toll bridge and approaches across these waters at a point suitable to the interests of navigation and to reconstruct, repair and improve the same; to construct, maintain and operate a tunnel under these waters and to reconstruct, repair and improve the same; and to issue and sell negotiable revenue bonds of the Authority for such purposes.(b) Such bonds shall be authorized by ordinances as the Authority may determine from time to time, such ordinances to contain such provisions with respect to the form thereof and maturity, interest rate, sinking fund, redemption and refunding as are customary and usual. Such bonds shall be issued under a trust indenture from the Authority to a corporate trustee, which indenture shall contain the usual and customary provisions with respect to the issuance of bonds, the application of the revenues of such bridge or tunnel for the creation of a sinking fund to provide for the payment of such bonds and interest thereon, the holding of the proceeds of the bonds in a special trust for the purpose of acquiring or constructing such bridge or tunnel and a first priority pledge and assignment by the Authority to the trustee under such trust indenture of the revenues of such bridge or tunnel over and above the cost of operation and maintenance thereof as security for the payment of the principal of and interest on such bonds. The Authority shall establish, maintain and collect tolls for transit over such bridge or through such tunnel acquired or constructed hereunder sufficient at all times to pay the cost of the operation and maintenance thereof and to pay the principal of and interest on the bonds issued hereunder. Such bonds and the coupons evidencing interest thereon shall constitute an irrevocable contract between the holders thereof and the Authority that such tolls shall always be sufficient therefor. No bonds issued hereunder shall bear interest at a rate exceeding the market prime rate and all such bonds so issued hereunder shall be sold for not less than par and accrued interest to the date of delivery and payment and may be sold at private sale without prior publication of notice thereof. Such bonds shall be payable solely and only from the revenues of the Authority pledged to the payment thereof.