Wash. Rev. Code § 36.96.040
After such hearings, the county legislative authority shall make written findings whether each of the special purpose districts that was a subject of the hearings meets each of the criteria of being "inactive." Whenever a special purpose district other than a public utility district has been found to meet a criterion of being inactive, or a public utility district has been found to meet both criteria of being inactive, the county legislative authority shall adopt an ordinance dissolving the special purpose district if it also makes additional written findings detailing why it is in the public interest that the special purpose district be dissolved, and shall provide a copy of the ordinance to the county treasurer. Except for the purpose of winding up its affairs as provided by this chapter, a special purpose district that is so dissolved shall cease to exist and the authority and obligation to carry out the purposes for which it was created shall cease thirty-one days after adoption of the dissolution ordinance.
RCW 36.96.040