S.D. Codified Laws § 46A-14-64
If a bond issue or other authorized long-term financing arrangement is authorized by the voters of the district, the managers shall immediately cause a written notice to be mailed to the owner or owners of each tract of land assessed of the amount of the assessment. The notice shall state that if the amount is not paid in full within thirty days after the date of the notice, bonds will be issued or payment contracts negotiated and that an assessment will be levied annually against the tract of ground for a period of not to exceed fifty years in an amount sufficient to pay the total assessment plus the interest due on the bonds. No suit to set aside the assessment may be brought after the expiration of thirty days from the date of the notice. The amount levied against each tract of land to pay for the bonds, or contract commitments, falling due each year and the interest on the bonds or contract commitments, shall be levied, certified to the proper county auditor, and collected the same as other taxes.
SDCL 46A-14-64