Oregon Revised Statutes Cities § 224.400

(1) Each municipality financing the cost of a sewerage system under authority of ORS 224.310 to 224.420 shall submit to the State Treasurer for approval a schedule of its rates and proposed method of collection of its sewerage charges. The rates shall be such as, in the judgment of the State Treasurer, shall provide sufficient funds with other revenues, if any, and ad valorem property taxes to liquidate, during the period approved by the State Treasurer, the indebtedness incurred by the municipality to defray the cost of the sewerage system and its appurtenances. Should the rates prove to be insufficient for such purpose, the State Treasurer may direct the municipality to increase the rates to the point at which the sewerage project becomes self-liquidating, and the municipality shall establish forthwith the rates prescribed by the State Treasurer.

(2) If the municipality does not have the ability to collect sewerage charges in connection with or as part of the charge for another service or utility that can be curtailed to secure collection, and if the State Treasurer so directs, delinquent assessments for sewerage charges shall be certified to the assessor of the county in which the municipality is located and shall be entered upon the tax rolls of the county and be collected and accounted for in the same manner in which city taxes are collected and accounted for. The charges shall constitute liens against the real property of the person against whom they are assessed.

(3) If required by the State Treasurer, the municipality shall obtain from the State Treasurer approval of the annual budgets and tax levies of the municipality, before they are certified to the clerk and assessor of the county in which the municipality is located, for extension upon the county tax rolls.