S.D. Codified Laws § 31-19-26
Current with legislation signed by the governor on or before 3/6/2024
A copy of the declaration of taking filed pursuant to § 31-19-23 and amendments thereto shall be served with the condemnation petition or by mailing a copy thereof to each of the known defendants by registered or certified mail at their last known post office address.
SDCL 31-19-26