U.S. Route 12 in South Dakota

This article is about the section of U.S. Route 12 in South Dakota. For the entire route, see U.S. Route 12.

U.S. Highway 12 (US 12) is a part of the United States Numbered Highway System that travels from Aberdeen, Washington, to Detroit, Michigan. In the state of South Dakota, US 12 extends from the North Dakota border east to the Minnesota border.

U.S. Highway 12
US 12 highlighted in red
Route information
Maintained by SDDOT
Length	319.24 mi[1] (513.77 km)
Existed	1926–present
Major junctions
West end	US 12 at the North Dakota state line
Major intersections	US 83 in Selby US 281 in Aberdeen I-29 / US 81 near Summit
East end	US 12 at the Minnesota state line
Location
Country	United States
State	South Dakota
Counties	Perkins, Corson, Walworth, Edmunds, Brown, Day, Roberts, Grant
Highway system
United States Numbered Highway System List Special Divided South Dakota State Trunk Highway System Interstate US State
← SD 11 → SD 12

Route description

US 12 enters South Dakota from North Dakota as a rural two-lane highway about 10 miles (16 km) west-northwest of Lemmon before entering the Standing Rock Indian Reservation. For approximately the next 70 miles (110 km), US 12 runs parallel to the border of North Dakota, sometimes within less than a mile (1.6 km). At Walker, US 12 heads southeast for 37 miles (60 km), where it crosses the Missouri River at Mobridge, exiting the reservation. From there, it continues east for 18 miles (29 km), until it meets with US 83 near Selby. It overlaps US 83 for seven miles (11 km). After leaving US 83, it turns due east and spends about 80 miles (130 km) as a rural two-lane highway again. A few miles before reaching Aberdeen, it becomes an at-grade expressway. After the junction with US 281, it goes back to being two lanes for a few miles through Aberdeen and past Aberdeen Regional Airport, before once again becoming a four-lane expressway, until two miles (3.2 km) before Waubay. East of Waubay it becomes again an at-grade expressway until it meets with I-29 near Summit. The speed limit from Aberdeen to I-29 is 70 mph (110 km/h) except through the communities of Groton, Webster, and Waubay. From there, it heads southeast 22 miles (35 km) until Milbank. At Milbank, it continues east for 12 miles (19 km), until it crosses into Minnesota at Big Stone City, just south of Big Stone Lake.^[2]

The South Dakota section of US 12 is legally defined at South Dakota Codified Laws § 31-4-132.^[3]

History

Major intersections

County	Location	mi[1]	km	Destinations	Notes
Perkins	White Butte Township	80.50	129.55	US 12 west – Hettinger	Continuation into North Dakota
	Lincoln Township	91.08	146.58	SD 73 south – Faith	Western end of SD 73 concurrency
Corson	Lemmon No. 2	101.68	163.64	SD 73 north to ND 49 north – New Leipzig	Eastern end of SD 73 concurrency
	Lake Township	132.11	212.61	SD 65 north to ND 31 north – Raleigh	Western end of SD 65 concurrency
		132.64	213.46	SD 65 south – Isabel	Eastern end of SD 65 concurrency
	Module:Jctint/USA warning: Unused argument(s): ctdab
	McLaughlin	159.32	256.40	SD 63 – Fort Yates, Little Eagle
	Mission Township	181.52	292.13	SD 20 west / Lewis and Clark Trail / Native American Scenic Byway south – Timber Lake	Western end of SD 20 concurrency
		184.58	297.05	SD 1806 south – Sitting Bull Monument	Western end of SD 1806 concurrency
Module:Jctint/USA warning: Unused argument(s): ctdab
185.69	298.84	SD 1806 north / Lewis and Clark Trail / Native American Scenic Byway north – Wakpala, Indian Memorial Recreation Area	Eastern end of SD 1806 concurrency
Module:Jctint/USA warning: Unused argument(s): ctdab
Missouri River (Lake Oahe)		186.18	299.63	US 12 Missouri River Bridge
Walworth	Mobridge Township	189.92	305.65	SD 1804 north (4th Avenue East) / Lewis and Clark Trail – Pollock	Western end of SD 1804 concurrency
	West Walworth	193.79	311.87	SD 1804 south – Akaska	Eastern end of SD 1804 concurrency
	West Walworth–East Walworth line	207.38	333.75	US 83 north – Mound City	Western end of US 83 concurrency
	Selby	209.96	337.90	SD 130 east (Scranton Street) – Java, Lake Hiddenwood Recreation Area	Western terminus of SD 130
	West Walworth–East Walworth line	214.08	344.53	US 83 south / SD 20 east / Lewis and Clark Trail to US 212	Eastern end of US 83/SD 20 concurrency
	East Walworth	220.94	355.57	SD 271 north – Java, Lake Hiddenwood Recreation Area
		226.06	363.81	SD 47 south – Hoven	Western end of SD 47 concurrency
Module:Jctint/USA warning: Unused argument(s): ctdab
Edmunds	Bowdle	233.07	375.09	SD 47 north – Eureka	Eastern end of SD 47 concurrency
	Cottonwood Lake–Glen township line	242.07	389.57	SD 253 north – Hosmer	Southern terminus of SD 253
	Roscoe	248.04	399.18	SD 247 north (Mitchell Street)	Southern terminus of SD 247
	Ipswich	263.10	423.42	SD 45 south (4th Street)	Western end of SD 45 concurrency
	Fountain Township	268.13	431.51	SD 45 north – Leola	Eastern end of SD 45 concurrency
Brown	Aberdeen	288.94	465.00	US 281 (19th Street) to SD 10 – Redfield
	Groton	309.02	497.32	SD 37 (Broadway Street) to SD 10 – Doland
Day	Bristol Township	326.37	525.24	SD 27 – Britton	Southern terminus of SD 27
	Webster	343.04	552.07	SD 25 (Main Street) to US 212 / SD 10 – Fort Sisseton State ParkModule:Jct error: Invalid "to" argument
Roberts	Summit Township	366.36	589.60	I-29 / US 81 – Watertown, Sisseton
Grant	Osceola–Kilborn township line	376.68	606.21	SD 123 – Wilmot	Southern terminus of SD 123
Grant	Milbank	389.06	626.13	SD 15 (Dakota Street) to US 212 – Hartford Beach State Park	Southern terminus of SD 123
	Big Stone City	399.02	642.16	SD 109 – Hartford Beach State Park	Southern terminus of SD 109
		399.74	643.32	US 12 east – Ortonville	Continuation into Minnesota
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus

See also

• U.S. roads portal