(2) A road assessment district formed under subsection (1) of this section shall continue in existence under the provisions of ORS 371.405 to 371.535 notwithstanding a growth in population exceeding 25,000, as shown by a subsequent decennial federal census, in the county where the road district was formed. [Amended by 1955 c.227 §2; 1971 c.727 §104; 1981 c.69 §1]