Wash. Rev. Code § 53.34.010
In addition to all other powers granted to port districts, any such district may, with the consent of the department of transportation, acquire by condemnation, purchase, lease, or gift, and may construct, reconstruct, maintain, operate, furnish, equip, improve, better, add to, extend, and lease to others in whole or in part and sell in whole or in part any one or more of the following port projects, within or without or partially within and partially without the corporate limits of the district whenever the commission of the district determines that any one or more of such projects are necessary for or convenient to the movement of commercial freight and passenger traffic a part of which traffic moves to, from, or through the territory of the district:
In connection with the acquisition or construction of any one or more of such projects the port districts may, with the consent of the state department of transportation, further acquire or construct, maintain, operate, or improve limited or unlimited access highway approaches of such length as the commission of such district deems advisable to provide means of interconnection of the facilities with public highways and of ingress and egress to any such project, including plazas and toll booths, and to construct and maintain under, along, over, or across any such project telephone, telegraph, or electric transmission wires and cables, fuel lines, gas transmission lines or mains, water transmission lines or mains, and other mechanical equipment not inconsistent with the appropriate use of the project, all for the purpose of obtaining revenues for the payment of the cost of the project.
Consistent with RCW 47.56.850, any toll, including any change in an existing toll rate, proposed under this section must first be reviewed and approved by the tolling authority designated in RCW 47.56.850 if the toll, or change in toll rate, would have a significant impact, as determined by the tolling authority, on the operation of any state facility.
RCW 53.34.010