The governing body of a municipality may levy a tax on all taxable property within the district in an amount necessary to finance the cost of the improvement, including maintenance and to pay the principal and interest on obligations issued pursuant to section 444.19. The tax shall be collected and paid over as other taxes, but shall be spread only upon the property described in the ordinance. The tax shall be disbursed by the governing body only for the benefit of district as established by the ordinance.