Wash. Rev. Code § 87.03.845
This section and RCW 87.03.847 through 87.03.855 provide the procedures by which a minor irrigation district may be merged into a major irrigation district as authorized by RCW 87.03.530(2).
To institute proceedings for such a merger, the board of directors of the minor district shall adopt a resolution requesting the board of directors of the major district to consider the merger, or proceedings for such a merger may be instituted by a petition requesting the board of directors of the major district to consider the merger, signed by ten owners of land within the minor district or five percent of the total number of landowners within the minor district, whichever is greater. However, if there are fewer than twenty owners of land within the minor irrigation district, the petition shall be signed by a majority of the landowners and filed with the board of directors of the major irrigation district.
For the purpose of determining the number of landowners required to initiate merger proceedings under this section, a husband and wife owning property as community property shall be considered a single landowner; two or more persons or entities holding title to property as tenants in common, joint tenants, tenants in partnership, or other form of joint ownership shall be considered a single landowner; and the petition requesting the merger shall be considered by the board of directors of the major irrigation district may be [if the petition is] signed by either the husband or wife and by any one of the co-owners of jointly owned property.
The board of directors of the major irrigation district shall consider the request at the next regularly scheduled meeting of the board of directors of the major district following its receipt of the minor district's request or at a special meeting called for the purpose of considering the request. If the board of the major district denies the request of the minor district, no further action on the request shall be taken.
If the board of the major district does not deny the request, it shall conduct a public hearing on the request and shall give notice regarding the hearing. The notice shall describe the proposed merger and shall be published once a week for two consecutive weeks preceding the date of the hearing and the last publication shall be not more than seven days before the date of the hearing. The notice shall contain a statement that unless the holders of title or evidence of title to at least twenty percent of the assessed lands within the major district file a protest opposing the merger with the board of the major district at or before the hearing, the board is free to approve the request for the merger without an election being conducted in the major district on the request. If the board of the major district is considering requests from more than one minor district, the hearing shall be conducted on all such requests.
RCW 87.03.845