Oregon Revised Statutes Public Financial Administration § 294.353

Subject to the provisions contained in the charter of any city or county or in any law relating to municipal corporations, when the necessity for maintaining any fund of the municipal corporation has ceased to exist and a balance remains in the fund, the governing body shall so declare by ordinance or other order and upon such declaration such balance shall forthwith be transferred to the general fund of the municipal corporation unless other provisions have been made in the original creation of the fund.