S.D. Codified Laws § 9-6-12
If a majority of all the votes cast at an election under § 9-6-10 shall be for dissolution and such vote shall have been given by two-fifths of all the legal voters in such municipality, as shown by the vote cast at the last preceding annual election therein, a statement of the vote signed by the mayor or president of the Board of Trustees and attested by the auditor or clerk shall be filed in the office of the register of deeds of the proper county; and such municipality shall, at the expiration of six months from the time of holding such election, cease to be a municipality, and the property belonging to it after the payment of its debts and liabilities shall be disposed of in such manner as the governing body may direct.
Such dissolution shall not affect the rights of any person under any contract with such municipality.
SDCL 9-6-12