A certified copy of the ordinance defining the reduced city or town limits together with a map showing the corporate limits as altered shall be filed in accordance with RCW 29A.76.020 and recorded in the office of the county auditor of the county in which the city or town is situated, upon the effective date of the ordinance. The new boundaries of the city or town shall take effect immediately after they are filed and recorded with the county auditor.
RCW 35.16.050