ORS § 225.490
Any city of this state participating in common facilities under ORS 225.450 to 225.490 may furnish money and provide property, both real and personal, and to the extent and in the manner provided by its charter issue and notwithstanding any other provision of law, sell, either at public or privately negotiated sale, revenue bonds pledging revenues of its electric system and its interest or share of the revenues derived from the common facilities and any additions or betterments thereto, in order to pay its respective share of the cost of the planning, financing, acquisition and construction thereof. All moneys paid or property supplied by any such city for the purpose of carrying out the powers conferred by ORS 225.450 to 225.490 are declared to be for a public purpose.
ORS 225.490