ORS § 225.300
Any filing made by any city upon the unappropriated waters of this state for use in the future development of a hydroelectric plant by such city shall be reserved to such city and shall not be subject to appropriation by any other person, municipality or corporation unless it is judicially determined that the filing exceeds the reasonable present and future requirements of such city. In that event the surplus or excess may, by judgment of a court of competent jurisdiction, be released and discharged from the filing. Proceedings in court for the determination of whether or not the filing by any city exceeds its reasonable present and future requirements may be instituted by the State of Oregon, by the Water Resources Commission in the name of and for the State of Oregon, or by any other applicant for the right to use the waters involved.
ORS 225.300