S.D. Codified Laws § 8-1-22
At the time and place so appointed such board of county commissioners shall proceed to the consideration of such petition, and shall at the same time afford opportunity to any resident of the civil township to be affected thereby to be heard in opposition thereto, and if upon such hearing it shall appear to such board that such petition is signed by and is in accordance with the wishes of sixty percent of the legal voters of the portion of said civil township outside the area of the village, such board shall proceed at once to divide such original civil township into separate civil townships, determine and fix the boundaries of such civil townships resulting from such division. All proceedings thereupon shall be as provided in §§ 8-1-7 to 8-1-9, inclusive, for the division and reorganization of townships.
SDCL 8-1-22