(1) Within the unincorporated territory of any county, the governing body of such county is hereby vested with jurisdiction, power, and authority to establish districts for the acquisition, construction, installation, operation, or maintenance of improvements or the provision of services authorized by this part 5. The governing body of a county may establish a district wholly or partially within the boundaries of any municipality or partially within the unincorporated territory of another county if such municipality or county consents by resolution to the establishment of such district.

(2) If a municipality annexes or incorporates any territory within an established district, such territory shall remain in the district unless the municipality notifies the district's board of the municipality's intent to exclude the territory annexed or incorporated from the district. If the municipality notifies the board of its intent to exclude such territory, such exclusion shall take effect January 1 of the year following such notice. Any property excluded from the district under this subsection (2) shall remain subject to payment of its share of any indebtedness or bonds that are outstanding on the date of such exclusion.

(3) At such time as all of the territory included within an existing district that has no outstanding indebtedness or bonds is annexed or incorporated into a municipality, the governing body of the municipality shall exercise all duties of the governing body of the district but continue to act under this section as if it were the board of county commissioners. The presiding officer of the governing body of the municipality shall be ex officio the presiding officer of the board, the clerk of the municipality shall be ex officio the secretary of the board, and the treasurer of the municipality shall be ex officio the treasurer of the board and district.