Oregon Revised Statutes Public Health and Safety § 454.310

(1) When a certified copy of the findings and order approving the proposal is filed with the governing body, the governing body shall order construction of the treatment works and proceed with the financing plan as specified in the order. As part of the construction of the treatment works, the governing body may require property owners in the affected area to connect to the treatment works. The governing body shall establish by ordinance the method the governing body will use to enforce a mandatory connection requirement.

(2) Within 12 months after receiving the Environmental Quality Commission's order the municipality shall prepare final plans and specifications for the treatment works and proceed in accordance with the time schedule to construct the facility.