(a) To serve unincorporated areas in the county; and
(b) For a service district established under ORS 451.410 to 451.600 and for which the county court serves as governing body, to serve all areas within or served by the district.
(2) Master plans adopted under this section shall be coordinated with the comprehensive plans of the affected cities and counties. [1955 c.509 §2; 1961 c.576 §1; 1963 c.515 §4; 1973 c.785 §3; 1989 c.429 §1]