Wash. Rev. Code § 91.08.030
The plan of such proposed waterway shall be presented to the board by a written petition of owners of lands which it is represented will be improved by the construction, deepening or widening of such waterway; and such petition shall be signed by the owners of thirty-five percent or more of the area of lands in the district, and shall be verified by one or more of the petitioners to the effect that the signatures attached are the genuine signature of the persons or corporations signing the same. Each petitioner shall add a description of the lands he or she owns. If petitioners are unmarried persons they shall so state. If lands are owned by married persons, husband and wife shall join in the petition. If a petitioner is a corporation, the signature shall be accompanied by a certified copy of a resolution of the board of directors or trustees of the corporation authorizing the person signing the petition for the corporation to execute it. If lands included in the petition are owned by minors, insane persons, or other persons under guardianship in this state, the petition may be signed by the guardians of such persons: PROVIDED, That the signature be accompanied by a certified copy of an order of the superior court having the guardianship of such person in charge, authorizing the guardian to sign the petition. A petition may consist of one or more separate papers or sheets which are identified with the subject matter.
The petitioners shall file with the board, with their petition, a map of the lands in the district and a statement showing each separate ownership of lands as shown by the public records of the county, and their location in the county, with the names of the owners as shown by such records, and the location of the proposed waterway if a new waterway is to be constructed. If an existing waterway is to be deepened the map shall show its location, and if it is to be widened the map shall show its location and the extent to which it is to be widened. With the petition there shall also be presented satisfactory evidence from the real property records of the county that the petitioners are severally the owners in fee simple of their respective tracts of land, and that all taxes and assessments due thereon are paid. If it is proposed that any lands in the district shall be filled with the material dug or dredged from such waterway, the petition shall so state, and the map of the district and plan of the improvement shall show the location, depth, and yardage of such fill. The petition may also fix the price per cubic yard at which such fill shall be charged to the land filled, which charge shall be added to the assessment for the improvement to be made upon such lands and be paid as a part thereof. If the price of filling is not fixed by the petition it may be fixed by the board.
At any time after the filing of such petition one or more of the petitioners may file and record in the office of the auditor of the county, notice of the pendency of the proceeding, describing the boundaries of the proposed district, and from the time of such filing all persons shall be deemed to have notice of the pendency of the proceeding and be bound thereby. Upon the hearing upon such petition, hereinafter provided, if the same be denied any person interested may file in the office of said county auditor a certified copy of the order denying the same, whereupon the auditor shall enter the discharge of the notice of the pendency of the proceeding on the margin of the record thereof. And the like discharge may be filed whenever the proceeding is terminated for any other reason.
RCW 91.08.030