Wash. Rev. Code § 85.32.170
The decision of the board upon any objection made within the time and in the manner prescribed in this chapter may be reviewed by the superior court of the county wherein the property in question is located. Any person aggrieved must file his or her petition for writ of review with the clerk of the superior court wherein the property is located within ten days after the roll affecting such aggrieved party was adopted by resolution, and he or she shall serve a copy thereof upon the board. The petition shall describe the property in question, set forth the written objections which were made to the decision, give the date of filing of such objections, and shall be signed by such party or someone in his or her behalf. The court shall forthwith grant such petition if correct as to form and filed in accordance with this section.
RCW 85.32.170