Wash. Rev. Code § 87.03.720
The board of directors of an irrigation district shall, after being notified by the legislative authority of the county or counties within which the irrigation district lies of the filing of the petition therefor, have the power to assent to the proposed merger with the irrigation district of that portion of a drainage improvement district, joint drainage improvement district, consolidated drainage improvement district, or water-sewer district within its boundaries at a hearing duly called by the board to consider the proposed merger if sufficient objections thereto have not been presented, as hereinafter provided.
RCW 87.03.720
Part headings not law-1999 c 153: See note following RCW 57.04.050.
Merger of drainage improvement district with irrigation district: RCW 85.08.830 through 85.08.890.