S.D. Codified Laws § 38-32-3.1
An election shall be held in each district in which a director's term is to expire. The election date and time shall be determined by the council but shall be between January first to February fifteenth, inclusive, closest to the pending vacancy's expiration date. The election shall be by official ballot, which shall be made available at the polling location. The council shall designate at least one polling location in each county within the district. The principal polling location in the county shall be at the county office of the Cooperative Extension Service of South Dakota State University, if available, or at a place specified by the council. If only one candidate is nominated in a district, no election is required in the district, and the council shall declare the nominee as elected and shall provide the nominee with a certificate of election pursuant to § 38-32-8.
SDCL 38-32-3.1