If the governing body of the municipality deems it advisable to pay the whole or any part of the cost of a municipal utility by special assessment warrants, it shall create a special assessment district by ordinance. The district shall include, as nearly as may be determined, all of the property in the municipality which will be benefited by the improvement, and may include the entire municipality or a portion thereof. The governing body thereafter shall adopt a     resolution of necessity and hold a hearing thereon, estimate the amount of the cost of the improvement, let a contract or contracts therefor, create a fund for the district, issue and sell the warrants of the municipality drawn on the fund, complete the work of the improvement, and assess the property benefited thereby upon notice and in the form and manner specified by the provisions of chapters 40-22 through 40-26 insofar as such provisions are applicable to an improvement being made under this chapter. The special assessments levied shall be payable in equal annual installments extending over a period of not more than twenty years and shall bear interest at an annual rate of not more than one and one-half percentage points above the average net annual interest rate on any warrants for the payment of which they are pledged on the total amount of the assessments remaining unpaid.