S.D. Codified Laws § 31-4-14.5
The Transportation Commission may designate, by rules promulgated pursuant to chapter 1-26, a segment of the state trunk highway system as a minimum maintenance road if the commission determines that the segment is used only occasionally or intermittently for passenger or commercial travel. The commission shall publish a list of the state highway segments proposed to be designated as minimum maintenance segments each year and provide an opportunity for public input pursuant to chapter 1-26 before making the final designations. The commission shall identify the beginning and end points of the segment designated as minimum maintenance. A minimum maintenance segment may be maintained at a level less than the minimum standards for full maintenance roads, but shall be maintained at the level required to serve the occasional or intermittent traffic.
SDCL 31-4-14.5