Iowa Code § 357B.18
The trustees of a township, after notice and a public hearing, may withdraw the township or part of the township from a benefited fire district. Notice of the time, date and place of the hearing shall be published at least two weeks before the hearing in a newspaper having general circulation within the township. The notice shall also identify the area to be withdrawn. After the hearing on the proposed withdrawal, the township trustees, by majority vote, may withdraw the township or a part of the township from the benefited fire district. If the township trustees take final action to withdraw on or before March 1 of a fiscal year, the effective date of the withdrawal is the following July 1. However, if final action to withdraw is taken after March 1, the withdrawal is not effective until July 1 of the following calendar year. If bonds issued under section 357B.4 are outstanding at the time of withdrawal, the board of supervisors shall continue to levy an annual tax against the taxable property being withdrawn to pay its share of the outstanding obligation of the district relating to those bonds.
Iowa Code § 357B.18