A. Once a district has been organized under this act, any one or more public agencies not joining in the original organization agreement may subsequently join the district by becoming a signatory to the interlocal agreement. A public agency, by act of its governing body, may withdraw from a district after it is organized; however, such withdrawal shall not impair the rights of the district or other person in any contract, pledge of revenues or other financial obligation to which the public agency is a party. Such withdrawal may only be permitted by the board if rights of the district, other public agency members and holders of any obligations, contractual or otherwise, can be adequately protected by the authority or any settlement agreed upon with the withdrawing public agency.

B. A district may not provide water, sewage or any other services to an existing public agency or to persons within the geographic boundaries of an existing public agency which provides water or sewage services without the consent of the public agency, which consent shall be given by action of its governing body. In case of annexation of district territory by a municipality which is not a member of the district, the municipality may purchase at the appraised value the district's water and sewage facilities except those facilities necessary for the operation of the remainder of the district.