1.  Addition to territory.  After initial formation of a district, a municipality may join the district upon vote of the municipality's legislative body and upon a 2/3 vote of the board of directors. The board of directors shall determine the terms and conditions to be met by the joining municipality.  

2.  Withdrawal from district.  By vote of its legislative body, a municipality may elect to withdraw from the district. Withdrawal must take effect at the end of a district fiscal year, after the municipality has given the board of directors at least one year's written notice of its intention to withdraw. The municipality shall pay its proportionate share of the current indebtedness of the district before withdrawal and shall agree by appropriate written document to pay its proportionate share of any long-term indebtedness of the district as that indebtedness becomes due and payable. During the period of notice, the withdrawing municipality does not become liable for any capital expenditures or borrowings that may be made by the district. The proportionate share of the withdrawing municipality in any current and long-term indebtedness of the district must be in accordance with the formula then in effect for payment of the current and long-term indebtedness.