Oregon Revised Statutes Protection from Fire § 478.228

The boundaries or proposed boundaries of election subdistricts proposed or established within a district under ORS 478.225 from which directors are to be nominated or elected shall be as nearly equal in population as is feasible according to the latest available federal census data and shall be adjusted by the board to apportion population, to follow wherever practicable existent election precinct boundaries and to reflect boundary changes of the district. The boundaries shall be determined or adjusted by the board prior to submitting the question of election subdistricts to the electors under ORS 478.225.