Section 313A.12 - Revenue bonds1. The department is hereby authorized and empowered to issue revenue bonds for the acquisition, purchase, or construction of any interstate bridge. Any and all bonds issued by the department for the acquisition, purchase, or construction of any interstate bridge under the authority of this chapter shall be issued in the name of the department and shall constitute obligations only of the department, shall be identified by some appropriate name, and shall contain a recital on the face thereof that the payment or redemption of said bonds and the payment of the interest thereon are secured by a direct charge and lien upon the tolls and other revenues of any nature whatever received from the operation of the particular bridge for the acquisition, purchase, or construction of which the bonds are issued and of such other bridge or bridges as may have been pledged therefor, and that neither the payment of the principal or any part thereof nor of the interest thereon or any part thereof constitutes a debt, liability, or obligation of the state of Iowa. When it is determined by the department to be in the best public interest, any bonds issued under the provisions of this chapter may be refunded and refinanced at a lower rate, the same rate or a higher rate or rates of interest and from time to time as often as the department shall find it to be advisable and necessary so to do. Bonds issued to refund other bonds theretofore issued by the department under the provisions of this chapter may either be sold in the manner hereinafter provided and the proceeds thereof applied to the payment of the bonds being refunded, or the refunding bonds may be exchanged for and in payment and discharge of the bonds being refunded. The refunding bonds may be sold or exchanged in installments at different times or an entire issue or series may be sold or exchanged at one time. Any issue or series of refunding bonds may be exchanged in part or sold in part in installments at different times or at one time. The refunding bonds may be sold at any time on, before, or after the maturity of any of the outstanding bonds to be refinanced thereby and may be issued for the purpose of refunding a like or greater principal amount of bonds, except that the principal amount of the refunding bonds may exceed the principal amount of the bonds to be refunded to the extent necessary to pay any premium due on the call of the bonds to be refunded or to fund interest in arrears or about to become due. The gross revenues of any toll bridge pledged to the payment of the bonds being refunded, together with the unpledged gross revenues of any other toll bridges located within ten miles of said bridge, may be pledged by the department to pay the principal of and interest on the refunding bonds and to create and maintain reserves therefor.2. The department is empowered to receive and accept funds from the state of Iowa or the federal government or any other state upon a cooperative or other basis for the acquisition, purchase, or construction of any interstate bridge authorized under the provisions of this chapter and is empowered to enter into such agreements with the state of Iowa or any other state or the federal government as may be required for the securing of such funds.3. The department is authorized and empowered to spend from annual primary road fund receipts sufficient moneys to pay the cost of operation, maintenance, insurance, collection of tolls and accounting therefor and all other charges incidental to the operation and maintenance of any toll bridge administered under the provisions of this chapter. However, said annual primary road fund receipts shall be used only to pay such costs and charges with respect to that part of the bridge which is located within the state of Iowa.4. The department may also issue its revenue bonds to pay all or any part of the cost of acquiring two or more existing interstate bridges and any partially constructed interstate bridge, all located within ten miles of each other, of completing the partially constructed bridge and of dismantling the bridge which it is designed to replace, and to impose and collect tolls on all of such bridges and to pledge the revenues derived therefrom to the payment of the bonds issued to finance such project. The department may also issue its revenue bonds to pay all or any part of the cost of reconstructing, completing, improving, repairing, or remodeling any interstate bridge or partially constructed bridge, impose and collect tolls, and pledge the bridge revenues to the payment of said bonds.C71, 73, 75, 77, 79, 81, §313A.12