S.D. Codified Laws § 5-2-17
No lands belonging to the state within areas to be irrigated from works constructed or controlled by the United States, or its duly authorized agencies, shall be sold except in conformity with the classification of farm units by the United States, and the title to such lands shall not pass from the state until the applicant therefor shall have fully complied with the provisions of the laws of the United States and the regulations thereunder concerning the acquisition of the right to use water from such works, and shall produce the evidence thereof duly issued. After the withdrawal of lands by the United States for any irrigation project, no application for the purchase of state lands within the limits of such withdrawal shall be accepted except upon the conditions prescribed in this section.
SDCL 5-2-17