When a sidewalk or sidewalks has or have been constructed or reconstructed and where special assessments must be levied for the expense thereof, the governing body shall, as soon as the cost is ascertained, levy an assessment against the lot or piece of land chargeable therefor, by ordinance, and the property owner shall have thirty days after the publication of the ordinance within which to make full payment of the assessment. The city clerk shall mail a notice not less than fifteen days prior to the end of the thirty days to the owner of the property as shown on the records of the office of the register of deeds, but failure of the owner to receive the notice shall not affect the validity of the assessment. Any suit challenging the validity of the proceedings or the amount of the assessment must be filed within thirty days after the publication of the assessment ordinance.