Wash. Rev. Code § 90.16.020
Any person or persons, or company now incorporated, or that may hereafter become incorporated under the laws of this state, for the purpose of mining or manufacturing, shall have the right to purchase or appropriate and take possession of and divert from its natural channel, and use and hold the waters of any river, creek or stream in this state that may be required for the mining and manufacturing purposes of any such person or persons, corporation or corporations, and to construct all dams, canals, reservoirs, ditches, pipes, flumes and aqueducts, suitable and necessary for the controlling, directing and running such waters to their mines or manufacturing establishments of any such person or persons, corporation or corporations, where the same may be intended to be utilized for such purposes: PROVIDED, That no such appropriation or diversion of the waters of any such river, creek, or stream, from its natural channel; nor shall any such dam, canal, reservoir, ditch, pipe, flume or aqueduct, be constructed to the detriment of any person or persons, corporation or corporations, occupying the lands or being located below the point or place of such appropriation or diversion on any such stream or its tributaries, or above or below such dam, canal, reservoir, ditch, pipe, flume or aqueduct, or of the owners of the lands, through which the waters run in the natural course for the deprivation of the same, or the owners of the land through or upon which such dam, canal, reservoirs, ditch, pipe, flume or aqueduct, may pass through or over, or be situated upon, unless just and adequate compensation be previously ascertained and paid therefor.
RCW 90.16.020