S.D. Codified Laws § 31-4-228 (2026)
The state trunk highway system includes the following in Lyman County: From a point on Interstate Highway 90 south of Kennebec north of the southeast corner of section eighteen, township one hundred five north, range seventy-five west, thence north via Kennebec to State Highway 1806 near the northeast corner of section eighteen, township one hundred seven north, range seventy-five west.
Source: SL 1984, ch 209 , § 101.