Wash. Rev. Code § 17.04.230
Any interested party may appeal from the decision and order of the board of directors of such district to the superior court of the county in which such district is located, by serving written notice of appeal on the chair of the board of directors and by filing in the office of the clerk of the superior court a copy of said notice of appeal with proof of service attached, together with a good and sufficient cost bond in the sum of two hundred dollars, said cost bond to run to such district and in all respects to comply with the laws relating to cost bonds required of nonresident plaintiffs in the superior court. Said notice must be served and filed within ten days from the date of the decision and order of such board of directors, and said bond must be filed within five days after the filing of such notice of appeal. Whenever notice of appeal and the cost bond as herein provided shall have been filed with the clerk of the superior court, the clerk shall notify the board of directors of such district thereof, and such board shall forthwith certify to said court all notices and records in said matters, together with proof of service, and a true copy of the order and decision pertaining thereto made by such board. If no appeal be perfected within ten days from the decision and order of such board, the same shall be deemed confirmed and the board shall certify the amount of such charges to the county treasurer who shall enter the same on the tax rolls against the land. When an appeal is perfected the matter shall be heard in the superior court de novo and the court's decision shall be conclusive on all persons served under this chapter: PROVIDED, That appellate review of the order or decision of the superior court in the manner provided by existing laws, and upon the conclusion of such review, the amount of charges and costs adjudged to be paid shall be certified by the clerk of the superior court to the county treasurer and said treasurer shall proceed to enter the same on his or her rolls against the lands affected.
RCW 17.04.230
Appeals to supreme court: Rules of court: See Rules of Appellate Procedure.
Severability-1988 c 202: See note following RCW 2.24.050.
Cost bonds, civil procedure: RCW 4.84.210 through 4.84.240.