2010 South Dakota Code
Title 31 - HIGHWAYS AND BRIDGES
Chapter 04 - State Trunk Highway System
Section 31-4-152 - Interstate Highway 29 from Iowa to North Dakota.

31-4-152. Interstate Highway 29 from Iowa to North Dakota. The state trunk highway system includes the following in Union, Lincoln, Minnehaha, Moody, Brookings, Deuel, Hamlin, Codington, Grant, and Roberts counties:
From a point on the Iowa state line near the center of section twenty-six, township eighty-nine north, range forty-eight west, thence northerly via North Sioux City, Sioux Falls, Brookings, and Watertown to the North Dakota state line on the north line of section thirty, township one hundred twenty-nine north, range forty-nine west.

Source: SL 1984, ch 209, § 25.