Oregon Revised Statutes Water Resources: Irrigation, Drainage, Flood Control, Reclamation § 541.310

In any suit wherein the state is a party, for determination of a right to the use of the waters of any stream system, all who claim the right to use the waters shall be made parties. When any such suit has been filed the court shall call upon the Water Resources Commission to make or furnish a complete hydrographic survey of the stream system as provided in ORS 541.220, in order to obtain all data necessary to the determination of the rights involved. The disbursements made in litigating the rights involved in the suit shall be taxed by the court as in other equity suits.