S.D. Codified Laws § 32-20A-4 (2026)
The Department of Transportation may restrict or prohibit the use of snowmobiles on highways as defined in subdivision 31-1-5(1) under its jurisdiction upon its conspicuously posting of such highway or portion thereof by signs adopted by the transportation commission. A violation of this section is a Class 2 misdemeanor.
Source: SL 1971, ch 182 , § 4; SL 1973, ch 2 , § 232; SL 1979, ch 355 , §§ 17, 18; SL 1983, ch 391 , § 17; SL 1984, ch 207 , § 1; SL 1989, ch 255 , § 117.