The state trunk highway system includes the following in Union, Lincoln, and Minnehaha counties:
(1) From a point on Franklin Street near Elk Point near Interstate Highway 29 Business Loop, thence northerly via Elk Point to State Highway 50 north of Elk Point;
(2) From a point on State Highway 48 south of Alcester, thence northerly via Alcester to 57th Street in Sioux Falls;
(3) From a point on State Highway 42 east of Sioux Falls, thence northerly and easterly via Brandon and Garretson to the Minnesota state line.