RCW 90.14.170

Any person entitled to divert or withdraw waters of the state by virtue of his or her ownership of land abutting a stream, lake, or watercourse, who abandons the same, or who voluntarily fails, without sufficient cause, to beneficially use all or any part of said right to withdraw or divert said water for any period of five successive years after July 1, 1967, shall relinquish such right or portion thereof, and such right or portion thereof shall revert to the state, and the waters affected by said right shall become available for appropriation in accordance with the provisions of RCW 90.03.250.