Oregon Revised Statutes Public Organizations for Community Service § 264.480

(1) Notwithstanding ORS 198.910 and 198.915, when, at an election on consolidation or merger, a majority of the votes cast in each affected district is in favor of merger or consolidation or when merger or consolidation of districts is approved by a final order of a local government boundary commission, if all but one of the affected districts together contain fewer than 20 percent of the electors or owners of land within the successor or surviving district, the district board of the district containing the largest number of electors or owners of land shall serve as the district board of the surviving or successor district. The terms of office of members of the district board of the surviving or successor district chosen under this subsection shall not be affected by the merger or consolidation.

(2) The board selected under subsection (1) of this section or ORS 198.912 shall immediately meet as required by ORS 198.910, organize as provided by this chapter and, by resolution, declare the districts merged or consolidated. In areas outside the jurisdiction of a local government boundary commission, the merger or consolidation is complete from the date of adoption of the resolution. Within the jurisdiction of a local government boundary commission, the merger or consolidation takes effect as provided in ORS 199.480 (1)(c).

(3) For purposes of ad valorem taxation, a boundary change must be filed in final approved form with the county assessor and the Department of Revenue as provided in ORS 308.225.