The only significant exception was in northeast South Dakota, where SD 37 originally went westward from Groton to Bath, then north via Columbia to Houghton, where it continued to Hecla.

A seasonal ferry was in place to carry traffic across the river.

The segment between Huron and Mitchell was upgraded to a 4-lane expressway, and was largely completed by 2004.

A minor rerouting around the west end of Mitchell occurred, resulting in a 2-mile (3.2 km) concurrency with Interstate 90.

The route of SD 37 is defined in South Dakota Codified Laws § 31-4-158.