(1)(a) The state may acquire all or portions of existing surface water or groundwater rights, by purchase, gift, or other appropriate means other than by condemnation, from any person or entity or combination of persons or entities. Once acquired, such rights are trust water rights. A water right acquired by the state that is expressly conditioned to limit its use to instream purposes shall be administered as a trust water right in compliance with that condition.

(b) If the holder of a right to surface water or groundwater chooses to donate all or a portion of the person's water right to the trust water system to assist in providing instream flows or to preserve surface water or groundwater resources on a temporary or permanent basis, the department shall accept the donation on such terms as the person may prescribe as long as the donation satisfies the requirements of subsection (4) of this section and the other applicable requirements of this chapter and the terms prescribed are relevant and material to protecting any interest in the water right retained by the donor. Once accepted, such rights are trust water rights within the conditions prescribed by the donor.

(2) The department may enter into leases, contracts, or such other arrangements with other persons or entities as appropriate, to ensure that trust water rights acquired in accordance with this chapter may be exercised to the fullest possible extent.

(3) Trust water rights may be acquired by the state on a temporary or permanent basis.

(4) Except as provided in subsections (10), (11), and (12) of this section, a water right donated under subsection (1)(b) of this section shall not exceed the extent to which the water right was exercised during the five years before the donation nor may the total of any portion of the water right remaining with the donor plus the donated portion of the water right exceed the extent to which the water right was exercised during the five years before the donation. A water right holder who believes his or her water right has been impaired by a trust water right donated under subsection (1)(b) of this section may request that the department review the impairment claim. If the department determines that a trust water right resulting from a donation under subsection (1)(b) of this section is impairing existing water rights in violation of RCW 90.42.070, the trust water right shall be altered by the department to eliminate the impairment. Any decision of the department to alter or not to alter a trust water right donated under subsection (1)(b) of this section is appealable to the pollution control hearings board under RCW 43.21B.230. A donated water right's status as a trust water right under this subsection is not evidence of the validity or quantity of the water right.

(5) The provisions of RCW 90.03.380 and 90.03.390 do not apply to donations for instream flows described in subsection (1)(b) of this section, but do apply to other transfers of water rights under this section except that the consumptive quantity of a trust water right acquired by the state and held or authorized for use by the department is equal to the consumptive quantity of the right prior to transfer into the trust water rights program.

(6) No funds may be expended for the purchase of water rights by the state pursuant to this section unless specifically appropriated for this purpose by the legislature.

(7) Any water right conveyed to the trust water right system as a gift that is expressly conditioned to limit its use to instream purposes shall be managed by the department for public purposes to ensure that it qualifies as a gift that is deductible for federal income taxation purposes for the person or entity conveying the water right.

(8) Except as provided in subsections (10) and (11) of this section, if the department acquires a trust water right by lease, the amount of the trust water right shall not exceed the extent to which the water right was exercised during the five years before the acquisition was made nor may the total of any portion of the water right remaining with the original water right holder plus the portion of the water right leased by the department exceed the extent to which the water right was exercised during the five years before the acquisition. A water right holder who believes his or her water right has been impaired by a trust water right leased under this subsection may request that the department review the impairment claim. If the department determines that a trust water right resulting from the leasing of that trust water right leased under this subsection is impairing existing water rights in violation of RCW 90.42.070, the trust water right shall be altered by the department to eliminate the impairment. Any decision of the department to alter or not to alter a trust water right leased under this subsection is appealable to the pollution control hearings board under RCW 43.21B.230. The department's leasing of a trust water right under this subsection is not evidence of the validity or quantity of the water right.

(9) For a water right donated to or acquired by the trust water rights program on a temporary basis, the full quantity of water diverted or withdrawn to exercise the right before the donation or acquisition shall be placed in the trust water rights program and shall revert to the donor or person from whom it was acquired when the trust period ends. For a trust water right acquired by the state and held or authorized for use by the department, the consumptive quantity of the right when it reverts to the donor or person from whom it was acquired is equal to the consumptive quantity of the right prior to transfer into the trust water rights program.

(10) For water rights donated or leased under subsection (4) or (8) of this section where nonuse of the water right is excused under RCW 90.14.140(1):

(a) The department shall calculate the amount of water eligible to be acquired by looking at the extent to which the right was exercised during the most recent five-year period preceding the date where nonuse of the water right was excused under RCW 90.14.140(1); and

(b) The total of the donated or leased portion of the water right and the portion of the water right remaining with the water right holder shall not exceed the extent to which the water right was exercised during the most recent five-year period preceding the date nonuse of the water right was excused under RCW 90.14.140(1).

(11) For water rights donated or leased under subsection (4) or (8) of this section where nonuse of the water right is exempt under RCW 90.14.140(2) (a) or (d):

(a) The amount of water eligible to be acquired shall be based on historical beneficial use; and

(b) The total of the donated or leased portion of the water right and the portion of the water right the water right holder continues to use shall not exceed the historical beneficial use of that right during the duration of the trust.

(12) Upon a request made by a water right holder to the department on or before June 30, 2021, a water right banked pursuant to *RCW 90.92.070, as that section existed on April 15, 2021, must be accepted by the department as a temporary trust water right donation for a period of up to two years, in the same quantity that the water right was banked pursuant to *RCW 90.92.070.

*Reviser's note: RCW 90.92.070 expired June 30, 2021, pursuant to 2009 c 183 s 20 and 2019 c 78 s 4.

Effective date—2021 c 110: "This act is necessary for the immediate preservation of the public peace, health, or safety, or support of the state government and its existing public institutions, and takes effect immediately [April 21, 2021]." [ 2021 c 110 s 2.]

Findings—Intent—2009 c 283: See note following RCW 90.42.100.

Finding—Intent—Severability—Effective date—2001 c 237: See notes following RCW 90.82.040.

Intent—2001 c 237: See note following RCW 90.66.065.

Purposes—1991 c 347: See note following RCW 90.42.005.