Wash. Rev. Code § 8.04.010
Whenever any officer, board, commission, or other body representing the state is authorized by the legislature to acquire any land, real estate, premises, or other property, deemed necessary for the public uses of the state, or any department or institution thereof, the attorney general shall present to the superior court of the county in which the land, real estate, premises, or other property so sought to be acquired or appropriated is situated, a petition in which the land, real estate, premises, or other property sought to be appropriated shall be described with reasonable certainty, and setting forth the name of each and every owner, encumbrancer, or other person or party interested therein, or any part thereof, insofar as can be ascertained from the public records, the object for which the property is sought to be appropriated, and praying that a jury be impanelled to ascertain and determine the compensation to be made in money to such owner or owners, respectively, and to all tenants, encumbrancers, and others interested, for taking such land, real estate, premises, or other property, or in case a jury is waived, as in other civil cases in courts of record, in the manner prescribed by law, then that the compensation to be made as aforesaid be ascertained and determined by the court.
RCW 8.04.010