As security for the payment of any obligations agreed to in any swap agreement, as defined in subdivision (3) of Section 41-1-41, the department may pledge for payment of the obligations, all or any part of its docks facilities revenues; provided, however, that any pledge of its docks facilities revenues, in the discretion of the department, may be on parity with or subordinate to the pledge securing any of its docks facilities revenue bonds or other obligations.
Ala. Code § 33-2-203 (1975)