Wash. Rev. Code § 35.61.365
(1) As provided in this section, a city, town, or county may withdraw that portion of the city, town, or county from a metropolitan park district that was formed under this chapter when:
(2)
(6)
(a) An area that has been withdrawn from the boundaries of a metropolitan park district under this section may be reannexed into the metropolitan park district upon:
[ 2019 c 138 s 4.]