RCW 90.38.902: Existing rights not impaired.

(1) Nothing in this chapter shall authorize the impairment of, or operate to impair, any existing water rights.

(2) Nothing in this chapter may be construed to limit, impair, waive, abrogate, or diminish:

(a) Any treaty or other rights of the Yakama Nation;

(b) Any powers, rights, or authorities conferred upon irrigation districts under existing law;

(c) Any rights or jurisdictions of the United States, the state of Washington, or other person or entity over waters in the Yakima river basin.