ORS § 540.631
Whenever it appears to the satisfaction of the Water Resources Commission upon the commission's own determination or upon evidence submitted to the commission by any person that a perfected and developed water right has been forfeited as provided in ORS 540.610(1), and would not be rebutted under ORS 540.610(2), the commission shall initiate proceedings for the cancellation of such water right by causing written notice of such initiation of proceedings to be given by registered or certified mail, return receipt requested, to the legal owner of the lands to which the water right is appurtenant and to the occupant of such lands. The notice to the legal owner shall be addressed to the legal owner at the owner's last address of record in the office of the county assessor of the county in which the lands are located. The notice shall contain a complete description of the water right and of the lands to which the water right is appurtenant. The notice shall state that the legal owner or the occupant has a period of 60 days from the date of the mailing of the notice within which to protest the proposed cancellation of the water right.
ORS 540.631