(a) A county that has outstanding bonds payable from the revenue of a toll bridge or bridges may issue additional bonds to the extent and under the conditions prescribed by the provisions of the outstanding bonds and the proceedings related to those bonds, including any trust indenture securing those bonds. The additional bonds may be secured by a pledge of and a lien on the net revenues of the bridge or bridges on a parity with the outstanding bonds under the conditions set out in the proceedings or trust indenture securing and authorizing the outstanding bonds.
(b) A county that has acquired a toll bridge or bridges under this chapter may, in the manner provided by this chapter for the issuance of original bonds, issue and deliver subsequent bonds to repair, improve, reconstruct, or replace a toll bridge. The issuance of bonds under this subsection is subject to the restrictions contained in the resolution or order of the commissioners court authorizing the original bonds and in the deed of indenture, if any, securing the issuance of the original issue of bonds.