S.D. Codified Laws § 6-16-2
The application for organization shall be a petition verified by one or more circulators by affidavit stating that each affiant personally witnessed the signatures on the petition and believe the signatures to be genuine. Except as provided in this section, the petition shall be signed by at least twenty-five percent of the registered voters within the proposed district. If the proposed district is in two or more counties, a petition shall be filed in each county and each petition shall be signed by at least twenty-five percent of the registered voters within the proposed district in that county. The petition shall be accompanied by a deposit covering the estimated costs as determined by the county auditor of the public notices and the conduct of the election for the formation of the district. The county auditor may waive the deposit or payment requirement or may specify other arrangements for payment of the publication and election costs. If the district to be formed is a road district, the petition shall conform to the requirements of § 31-12A-3 and shall be signed by at least twenty-five percent of the eligible voters of the district as defined in § 31-12A-1.2. If the district to be formed is a watershed district, the petition shall be signed by at least twenty-five percent of the eligible voters of the district as defined in § 46A-14-15.1 and as provided in § 46A-14-5. If the district to be formed is a water project district, any petition required by this section shall be signed by qualified voters of the proposed district, as defined in §§ 46A-18-2.1 and 46A-18-2.2, in the appropriate county.
SDCL 6-16-2