S.D. Codified Laws § 31-12-5
Current with legislation signed by the governor on or before 3/6/2024
The construction, improvement, maintenance, and repair of the county highway system, except as provided for state trunk highways shall be under the supervision of the county superintendent of highways in organized counties, who shall formulate and direct the policy of the county for the construction, improvement, maintenance, and repair of the county highway system.
SDCL 31-12-5