S.D. Codified Laws § 43-17-4 (2026)
In all cases where the opposite banks of any streams not navigable belong to different persons, the stream and the bed thereof shall become common to both.
Source: CivC 1877, § 266; CL 1887, § 2782; RCivC 1903, § 289; RC 1919, § 359; SDC 1939, § 51.0703.