2010 South Dakota Code
Title 31 - HIGHWAYS AND BRIDGES
Chapter 04 - State Trunk Highway System
Section 31-4-146 - State Highway 21 from State Highway 28 to U.S. Highway 81.

31-4-146. State Highway 21 from State Highway 28 to U.S. Highway 81. The state trunk highway system includes the following in Hamlin County:
From a point on State Highway 28 at Lake Norden near the south line of section seventeen, township one hundred thirteen north, range fifty-three west, thence northerly and east via Hayti to U.S. Highway 81 east of Hayti near the northeast corner of section twenty-five, township one hundred fourteen north, range fifty-three west.

Source: SL 1984, ch 209, § 19.