Wash. Rev. Code § 70.44.047
If, as the result of redrawing the boundaries of commissioner districts as permitted or required under the provisions of this chapter, chapter 29A.76 RCW, or any other statute, more than the correct number of commissioners who are associated with commissioner districts reside in the same commissioner district, a commissioner or commissioners residing in that redrawn commissioner district equal in number to the number of commissioners in excess of the correct number shall be assigned to the drawn commissioner district or districts in which less than the correct number of commissioners associated with commissioner districts reside. The commissioner or commissioners who are so assigned shall be those with the shortest unexpired term or terms of office, but if the number of such commissioners with the same terms of office exceeds the number that are to be assigned, the board of commissioners shall select by lot from those commissioners which one or ones are assigned. A commissioner who is so assigned shall be deemed to be a resident of the commissioner district to which he or she is assigned for purposes of determining whether a position is vacant.
RCW 70.44.047
Effective date-1997 c 99: See note following RCW 70.44.040.