Wash. Rev. Code § 36.32.020
The board of county commissioners of each county shall divide their county into three commissioner districts so that each district shall comprise as nearly as possible one-third of the population of the county: PROVIDED, That the territory comprised in any voting precincts of such districts shall remain compact, and shall not be divided by the lines of said districts.
However, the commissioners of any county composed entirely of islands and with a population of less than thirty-five thousand may divide their county into three commissioner districts without regard to population, except that if any single island is included in more than one district, the districts on such island shall comprise, as nearly as possible, equal populations.
The commissioners of any county may authorize a change to their electoral system pursuant to RCW 29A.92.040. Except where necessary to comply with a court order issued pursuant to RCW 29A.92.110, and except in the case of an intervening census, the lines of the districts shall not be changed more often than once in four years and only when a full board of commissioners is present. Except when authorized under RCW 29A.92.115, the districts shall be designated as districts numbered one, two, and three.
RCW 36.32.020
Effective date- 2023 c 56: See note following RCW 29A.92.720.
Findings-Intent-Short title- 2018 c 113: See RCW 29A.92.005 and 29A.92.900.
Effective date-1982 c 226: See note following RCW 35.21.180.