Oregon Revised Statutes Utility Regulation § 772.310

(1) When the United States, the state, or any person, firm or corporation desires to convey water for irrigation, drainage or for any other beneficial purpose, and there is a canal or ditch already constructed that can be enlarged to convey the required quantity of water, then the United States, the state, or any such person, firm or corporation, or the owner or owners of the land through which a new canal or ditch would have to be constructed to convey the quantity of water necessary, may enlarge the canal or ditch already constructed, by compensating the owner of the canal or ditch to be enlarged for the damages, if any, caused by the enlargement.

(2) The enlargement may be made at any time between October 1 and March 1, but not any other times, unless upon agreement in writing with the owner or owners of the canal or ditch.

(3) If a water right permit is required under the applicable provisions of ORS chapter 537 in order to use, store or convey water within the enlargement, a person, firm, cooperative, association or corporation may not acquire an enlargement under this section before obtaining a water right permit or obtaining a final order of the Water Resources Department approving an application for a water right permit.