Wash. Rev. Code § 79.125.530
Immediately after establishing the harbor area provided for in RCW 79.125.520, it is the duty of the department to make a plat designating all first and second-class shorelands, not sold by the state of Washington, and to select for the use of the public out of the shorelands, or out of harbor areas, sites for slips, docks, wharves, warehouses, streets, avenues, parkways, boulevards, alleys, commercial waterways, and other public purposes, insofar as the shorelands may be available for any or all public purposes.
Upon the filing of the plat of shorelands with the reservations and selections in the department's Olympia office, the title to all selections for streets, avenues, and alleys shall vest in any city or town within the corporate limits of which they are situated, otherwise in the county in which they are situated. The title to and control of any land so selected and designated upon the plat for parkway and boulevard purposes shall, if the lands lie outside the corporate limits of any city or town, and if the lands form a part of the general parkway and boulevard system of the first-class city, be in the city. The title to all selections for commercial waterway purposes shall vest in the commercial waterway district in which they are situated, or for which selected, and the title to all selections for slips, docks, wharves, warehouses, and other purposes shall vest in the port district if they are situated in a port district, otherwise in the county in which they are situated, and any sales of the shorelands when otherwise permitted by law shall be made subject to the selection and reservation for public use.
RCW 79.125.530