Section 536.340 - Classification of water as to highest and best use and quantity of use; enforcement of laws concerning loss of water rights; prescribing preferences for future uses(1) Subject at all times to existing rights and priorities to use waters of this state, the Water Resources Commission: (a) May, by a water resources statement referred to in ORS 536.300(2), classify and reclassify the lakes, streams, underground reservoirs or other sources of water supply in this state as to the highest and best use and quantities of use thereof for the future in aid of an integrated and balanced program for the benefit of the state as a whole. The commission may so classify and reclassify portions of any such sources of water supply separately. Classification or reclassification of sources of water supply as provided in this subsection has the effect of restricting the use and quantities of use thereof to the uses and quantities of uses specified in the classification or reclassification, and no other uses or quantities of uses except as approved by the commission under ORS 536.370 to 536.390 or as accepted by the commission under ORS 536.295. Restrictions on use and quantities of use of a source of water supply resulting from a classification or reclassification under this subsection shall apply to the use of all waters of this state affected by the classification or reclassification, and shall apply to uses listed in ORS 537.545 that are initiated after the classification or reclassification that imposes the restriction.(b) Shall diligently enforce laws concerning cancellation, release and discharge of excessive unused claims to waters of this state to the end that such excessive and unused amounts may be made available for appropriation and beneficial use by the public.(c) May, by a water resources statement referred to in ORS 536.300(2) and subject to the preferential uses named in ORS 536.310(12), prescribe preferences for the future for particular uses and quantities of uses of the waters of any lake, stream or other source of water supply in this state in aid of the highest and best beneficial use and quantities of use thereof. In prescribing such preferences the commission shall give effect and due regard to the natural characteristics of such sources of water supply, the adjacent topography, the economy of such sources of water supply, the economy of the affected area, seasonal requirements of various users of such waters, the type of proposed use as between consumptive and nonconsumptive uses and other pertinent data.(2) In classifying or reclassifying a source of water supply or prescribing preferences for the future uses of a source of water supply under subsection (1) of this section, the commission shall: (a) Comply with the requirements set forth in the Water Resources Department coordination program developed pursuant to ORS 197.180; and(b) Cause notice of the hearing held under ORS 536.300(3) to be published in a newspaper of general circulation once each week for two successive weeks in each county: (A) In which waters affected by the action of the commission under subsection (1) of this section are located; or(B) That is located within the basin under consideration.(3) Before beginning any action under subsection (2) of this section that would limit new ground water uses that are exempt under ORS 537.545 from the requirement to obtain a water right, the commission shall: (a) Review the proposed action to determine whether the proposal is consistent with ORS 537.780;(b) Provide an opportunity for review by: (A) Any member of the Legislative Assembly who represents a district where the proposed action would apply; and(B) Any interim committee of the Legislative Assembly responsible for water-related issues; and(c) Receive and consider a recommendation on the proposal from the ground water advisory committee appointed under ORS 536.090.1955 c.707 §10(6); 1963 c.414 §1; 1989 c.9 §2; 1989 c.833 §54; 1997 c.510 §1; 2011 c. 52, § 1