Iowa Code § 384.71: Costs paid from applicable funds.

The whole or any part of the cost of construction or repair of a public improvement may be paid from the proceeds of the issuance of general obligation bonds under the provisions of section 384.25 or 384.26, as applicable, or from the fund or funds of the city authorized to be used for the particular type of improvement, and the council shall provide that the tax authorized for purposes of the fund or funds must be annually levied to the full extent necessary to reimburse the fund or funds for the amount paid for the construction or repair of the improvement.