Iowa Code § 357C.7
When a preliminary plat has been approved by the board of supervisors, an election shall be held within the district within sixty days to approve or disapprove the levy of a tax of not more than fifty-four cents per thousand dollars of assessed value on all the taxable property within the district, and to choose candidates for the offices of trustees of the district. Notice of the election, including the time and place of holding the same, shall be given in the same manner as for the original public hearing as provided herein. The vote shall be by ballot which shall state clearly the proposition to be voted upon, and any registered voter residing within the district at the time of the election shall be entitled to vote. It shall not be mandatory for the county commissioner of elections to conduct elections held pursuant to this chapter, but they shall be conducted in accordance with the provisions of chapter 49 where not in conflict with this chapter. Judges shall be appointed to serve without pay by the board of supervisors from among the registered voters of the district who will have charge of the election. The proposition shall be deemed to have carried if sixty percent of those voting thereon vote in favor of same.
Iowa Code § 357C.7
94 Acts, ch 1169, §64