Sioux County, North Dakota

Sioux County is a county located along the southern border of the U.S. state of North Dakota. As of the 2020 census, the population was 3,898, and was estimated to be 3,667 in 2025.

History

The county was created by proclamation of Governor Louis B. Hanna on September 3, 1914. It was named for the Native American Lakota, whose historic territory included this area. The county government organization was completed on September 12 of that year. The county lies entirely within the Standing Rock Sioux Reservation, forming the northernmost 30 percent of the reservation; the balance of the reservation is in South Dakota. It is the only county in North Dakota that is entirely within an Indian reservation. From 2013 to 2018, Sioux County was included in the Bismarck, ND Metropolitan Statistical Area.

Geography

Sioux County lies on the south line of North Dakota. Its south boundary line abuts the north boundary line of the state of South Dakota. Its north boundary line is formed by the east-northeastward-flowing Cedar Creek, which discharges into the Missouri River at the county's northeast corner, and its east boundary line is formed by the south-southeast-flowing Missouri River, which also forms Lake Oahe along the county boundary line. Porcupine Creek flows southeastward into the Missouri River, draining the northeastern part of the county. The county terrain consists of low rolling hills etched with gullies and drainages; the area is mostly devoted to agriculture. The terrain slopes to the east and south; its highest point is on the west line, near the southwestern corner of the county, at ASL.

According to the United States Census Bureau, the county has a total area of , of which is land and (3.03%) is water. It is the 34th largest county in North Dakota by total area.

The southwest corner counties of North Dakota (Adams, Billings, Bowman, Golden Valley, Grant, Hettinger, Slope, and Stark) observe Mountain Time. The counties of McKenzie, Dunn, and Sioux are split, observing Mountain Time in their western portions.

Major highways

25px North Dakota Highway 6
25px North Dakota Highway 24
25px North Dakota Highway 31
25px North Dakota Highway 49
25px North Dakota Highway 1806

Adjacent counties

Morton County - north (observes Central Time)
Emmons County - east (observes Central Time)
Corson County, South Dakota - south (observes Mountain Time)
Adams County - west (observes Mountain Time)
Grant County - northwest (observes Mountain Time)

Protected areas

Source:

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|footnote=U.S. Decennial Census 1790–1960 1900–1990 1990–2000 2010–2020

As of the 2023 American Community Survey, there are 1,067 estimated households in Sioux County with an average of 3.50 persons per household. The county has a median household income of $41,676. Approximately 34.9% of the county's population lives at or below the poverty line. Sioux County has an estimated 50.9% employment rate, with 11.2% of the population holding a bachelor's degree or higher and 86.9% holding a high school diploma.

The top five reported ancestries (people were allowed to report up to two ancestries, thus the figures will generally add to more than 100%) were English (92.7%), Spanish (0.3%), Indo-European (0.2%), Asian and Pacific Islander (0.0%), and Other (6.7%). !! Pop. 1990 !! Pop. 2000 !! Pop. 2010 !!

| White alone (NH)

| 1,265 (34.94%) || 905 (24.06%) || 577 (14.27%) || 517 (12.45%) || style='background: #ffffe6; |401 (10.29%)

| Black or African American alone (NH)

| 0 (0.00%) || 3 (0.08%) || 1 (0.02%) || 6 (0.14%) || style='background: #ffffe6; |3 (0.08%)

|- style='background: #F4A460;

| Native American or Alaska Native alone (NH)

| 2,329 (64.34%) || 2,812 (74.77%) || 3,365 (83.21%) || 3,433 (82.66%) || 3,281 (84.17%)

| Asian alone (NH)

| 5 (0.14%) || 12 (0.32%) || 1 (0.02%) || 4 (0.10%) || style='background: #ffffe6; |2 (0.05%)

| Pacific Islander alone (NH)

| — || — || 2 (0.05%) || 0 (0.00%) || style='background: #ffffe6; |0 (0.00%)

| Other race alone (NH)

| 0 (0.00%) || 0 (0.00%) || 0 (0.00%) || 0 (0.00%) || style='background: #ffffe6; |0 (0.00%)

| Mixed race or multiracial (NH)

| — || — || 33 (0.82%) || 111 (2.67%) || style='background: #ffffe6; |148 (3.80%)

| Hispanic or Latino (any race)

| 21 (0.58%) || 29 (0.77%) || 65 (1.61%) || 82 (1.97%) || style='background: #ffffe6; |63 (1.62%)

| Total

| 3,620 (100.00%) || 3,761 (100.00%) || 4,044 (100.00%) || 4,153 (100.00%) || style='background: #ffffe6; |3,898 (100.00%)

2020 census

As of the 2020 census, there were 3,898 people, 1,103 households, and 791 families residing in the county. The population density was . There were 1,277 housing units at an average density of .

There were 1,103 households in the county, of which 47.0% had children under the age of 18 living with them and 35.1% had a female householder with no spouse or partner present. About 21.4% of all households were made up of individuals and 6.5% had someone living alone who was 65 years of age or older. Of the 1,277 housing units, 13.6% were vacant; of the occupied units, 46.7% were owner-occupied and 53.3% were renter-occupied. The homeowner vacancy rate was 0.4% and the rental vacancy rate was 6.9%.

Education

School districts include:

Fort Yates Public School District 4 (in cooperation with the Standing Rock Bureau of Indian Education (BIE) grant school)
Selfridge Public School District 8
Solen Public School District 3

References

External links

Sioux County maps, Sheet 1 (eastern) and Sheet 2 (western), North Dakota DOT