Sec. 12. (a) This section does not apply to a joint board that includes three (3) or more counties in a drainage basin of more than one hundred thousand (100,000) acres.
(b) Whenever it appears, in any proceeding for the construction, reconstruction, or maintenance of a regulated drain, that a member of the board has an interest in the proceedings because of the member's ownership of real property affected by the drain, that member shall immediately disqualify himself or herself from serving on the board in those proceedings. However, the fact that county highways will be affected by any proceedings does not disqualify a regular member of the board.