Wash. Rev. Code § 35A.63.080
From the date of approval by the legislative body the comprehensive plan, its parts and modifications thereof, shall serve as a basic source of reference for future legislative and administrative action: PROVIDED, That the comprehensive plan shall not be construed as a regulation of property rights or land uses: PROVIDED, FURTHER, That no procedural irregularity or informality in the consideration, hearing, and development of the comprehensive plan or a part thereof, or any of its elements, shall affect the validity of any zoning ordinance or amendment thereto enacted by the code city after the approval of the comprehensive plan.
The comprehensive plan shall be consulted as a preliminary to the establishment, improvement, abandonment, or vacation of any street, park, public way, public building, or public structure, and no dedication of any street or other area for public use shall be accepted by the legislative body until the location, character, extent, and effect thereof shall have been considered by the planning agency with reference to the comprehensive plan. The legislative body shall specify the time within which the planning agency shall report and make a recommendation with respect thereto. Recommendations of the planning agency shall be advisory only.
RCW 35A.63.080