Oregon Revised Statutes Highways, Roads, Bridges and Ferries § 384.330

For the purpose of procuring funds, when necessary, with which to construct, maintain and operate the ferry service, the authority constructing, maintaining and operating the service may issue and sell revenue certificates, which shall not be the general obligation of the authority issuing them but shall be redeemable and payable solely from revenues accruing from the ferry service, over and above the cost of operating and maintaining the service. Such certificates may be purchased by the State of Oregon.