Oregon Revised Statutes Water Resources: Irrigation, Drainage, Flood Control, Reclamation § 547.475

The board of supervisors shall prepare a list or record of assessments and apportionments, giving the description of the ownership or holdings of each person therein assessed, which shall be certified by the board in the manner provided in ORS 310.060 not later than June 15 of each year to the county assessor of each county in which lands of the district are situated. The county assessor shall enter the assessment upon the county assessor's roll against the property therein described, in the same manner as other municipal taxes are entered by the county assessor.