The board is composed of:
(1) one member appointed by the governing body of each founding municipality;
(2) two members appointed by the commissioners court who reside in:
(A) an unincorporated area of the county; or
(B) a municipality in the authority that is not authorized to appoint a member to the board under Subdivision (1) or Section 460.254;
(3) each member appointed under Section 460.254, if applicable; and
(4) each nonvoting member appointed under Section 460.255.