Wash. Rev. Code § 53.04.080
At any general election or at any special election which may be called for that purpose the county legislative authority of any county in this state in which there exists a port district which is not coextensive with the limits of the county, shall on petition of the commissioners of such port district, by resolution, submit to the voters residing within the limits of any territory which the existing port district desires to annex or include in its enlarged port district, the proposition of enlarging the limits of such existing port districts so as to include therein the whole of the territory embraced within the boundaries of such county, or such territory as may be described in the petition by legal subdivisions. Such petition shall be filed with the county auditor, who shall forthwith transmit the same to the county legislative authority, who shall submit such proposition at the next general election, or, if such petition so request, the county legislative authority, shall at their first meeting after the date of filing such petition, by resolution, call a special election to be held in accordance with RCW 29A.04.321 and 29A.04.330. The notice of election shall state the boundaries of the proposed enlarged port district and the object of the special election. In submitting the question to the voters of the territory proposed to be annexed or included for their approval or rejection, the proposition shall be expressed on the ballots substantially in the following terms:
"Enlargement of the port of . . . . . ., yes." (Giving the name of the port district which it is proposed to enlarge);
"Enlargement of the port of . . . . . ., no." (Giving the name of the port district which it is proposed to enlarge).
Such election, whether general or special, shall be held in each precinct wholly or partially embraced within the limits of the territory proposed to be annexed or included and shall be conducted and the votes cast thereat counted, canvassed, and the returns thereof made in the manner provided by law for holding general or special county elections.
RCW 53.04.080
Elections: Title 29A RCW.