(a) A county or municipality that is a member of the district may petition the board for approval to withdraw from the district. The board may approve the petition only if:
(1) the district has no outstanding bonds; or
(2) the district has debt other than bonds and the board finds that the withdrawal of the county or municipality will not materially affect the ability of the district to repay the debt.
(b) If the board approves the petition, the county or municipality that withdrew from the district is not entitled to appoint directors to the board. The remaining counties or municipality by concurrent order or ordinance shall allocate among themselves the authority of the withdrawing county or municipality to appoint directors to the board.