Oregon Revised Statutes Water Resources: Irrigation, Drainage, Flood Control, Reclamation § 537.585

Except as otherwise provided in ORS 537.545 or 537.575 or 537.595 and subject to determination under ORS 537.670 to 537.695, actual and lawful application of ground water to beneficial use prior to August 3, 1955, by or under the authority of any person or public agency or by or under the authority of a predecessor in interest of such person or public agency, when registered under ORS 537.605 and 537.610, is recognized as a right to appropriate ground water to the extent of the maximum beneficial use thereof at any time within two years prior to August 3, 1955.