S.D. Codified Laws § 32-26-6
Current with legislation signed by the governor on or before 3/6/2024
On a roadway divided into lanes, a vehicle shall be driven as nearly as practicable entirely within a single lane and may not be moved from such lane until the driver has first ascertained that such movement can be made with safety. A violation of this section is a Class 2 misdemeanor.
SDCL 32-26-6