Polk County, Iowa

Coordinates: 41°41′06″N 93°34′13″W / 41.68500°N 93.57028°W / 41.68500; -93.57028
From Wikipedia, the free encyclopedia

Polk County
Polk County Courthouse
Polk County Courthouse
Flag of Polk County
Official seal of Polk County
Map of Iowa highlighting Polk County
Location within the U.S. state of Iowa
Map of the United States highlighting Iowa
Iowa's location within the U.S.
Coordinates: 41°41′06″N 93°34′13″W / 41.685°N 93.5703°W / 41.685; -93.5703
Country United States
State Iowa
FoundedJanuary 13, 1846
Named forJames K. Polk
SeatDes Moines
Largest cityDes Moines
Area
 • Total592 sq mi (1,530 km2)
 • Land574 sq mi (1,490 km2)
 • Water18 sq mi (50 km2)  3.0%
Population
 (2020)
 • Total492,401
 • Estimate 
(2022)
501,089 Increase
 • Density830/sq mi (320/km2)
Time zoneUTC−6 (Central)
 • Summer (DST)UTC−5 (CDT)
Congressional district3rd
Websitewww.polkcountyiowa.gov

Polk County is located in the U.S. state of Iowa. As of the 2020 census, the population was 492,401.[1] It is Iowa's most populous county, and home to over 15% of the state's residents. The county seat is Des Moines,[2] which is also the capital city of Iowa. Polk County is included in the Des Moines–West Des Moines, IA Metropolitan Statistical Area.[3]

History[edit]

On January 13, 1846, the legislative body of the Iowa Territory authorized the creation of twelve counties in the Territory,[4] with general descriptions of their boundaries. On January 17 they further enacted a resolution setting the effective date of the county government for Jasper and Polk Counties as March 1, 1846.[5] Polk County's name referred to United States President James K. Polk, who served from 1845 to 1849.

The first courthouse, a two-story structure, was built in Des Moines in 1846. Rapid settlement and commercial growth in the county soon rendered this building insufficient, so construction of a larger building was initiated in 1858. Due to construction delays and the onset of the Civil War, the structure was not completed until 1866. The present courthouse was erected in 1906, and in 1962 it was extensively renovated and enlarged.[6]

Geography[edit]

According to the United States Census Bureau, the county has a total area of 592 square miles (1,530 km2), of which 574 square miles (1,490 km2) is land and 18 square miles (47 km2) (3.0%) is water.[7] The county is bisected by the Des Moines River.

Major highways[edit]

Transit[edit]

Adjacent counties[edit]

Communities[edit]

Cities[edit]

Census-designated place[edit]

Unincorporated communities[edit]

Townships[edit]

Demographics[edit]

Historical population
CensusPop.Note
18504,513
186011,625157.6%
187027,857139.6%
188042,39552.2%
189065,41054.3%
190082,62426.3%
1910110,43833.7%
1920154,02939.5%
1930172,83712.2%
1940195,83513.3%
1950226,01015.4%
1960266,31517.8%
1970286,1017.4%
1980303,1706.0%
1990327,1407.9%
2000374,60114.5%
2010430,64015.0%
2020492,40114.3%
2022 (est.)501,089[8]1.8%
U.S. Decennial Census[9]
1790–1960[10] 1900–1990[11]
1990–2000[12] 2010–2020[1]
Population of Polk County from US census data

2020 census[edit]

As of the census of 2020, there were 492,401 people and 207,290 households in the county, with a population density of 833.5383/sq mi (321.8310/km2). 92.55% of the population reported being of one race. 66.18% were non-Hispanic White, 7.23% were Black, 9.76% were Hispanic, 0.46% were Native American, 4.98% were Asian, 0.06% were Native Hawaiian or Pacific Islander and 11.33% were some other race or more than one race. There were 210,184 housing units, of which 196,891 were occupied.

2010 census[edit]

As of the census of 2010, there were 430,640 people and 170,197 households in the county, with a population density of 756.371/sq mi (292.037/km2). There were 182,262 housing units, of which 170,197 were occupied.

2000 census[edit]

2000 Census Age Pyramid for Polk County

As of the census of 2000, there were 374,601 people, 149,112 households, and 96,624 families in the county. The population density was 658 inhabitants per square mile (254/km2). There were 156,447 housing units at an average density of 275 per square mile (106/km2). The racial makeup of the county was 88.34% White, 4.84% Black or African American, 0.27% Native American, 2.63% Asian, 0.06% Pacific Islander, 2.22% from other races, and 1.66% from two or more races. 4.40% of the population were Hispanic or Latino of any race. 25.9% were of German, 10.6% Irish, 9.0% English and 8.4% American ancestry.

Of the 149,112 households 32.20% had children under the age of 18 living with them, 51.00% were married couples living together, 10.30% had a female householder with no husband present, and 35.20% were non-families. 28.10% of households were one person and 8.60% were one person aged 65 or older. The average household size was 2.45 and the average family size was 3.04.

Age spread: 25.70% under the age of 18, 9.40% from 18 to 24, 32.20% from 25 to 44, 21.50% from 45 to 64, and 11.10% 65 or older. The median age was 34 years. For every 100 females, there were 94.20 males. For every 100 females age 18 and over, there were 90.70 males.

The median household income was $46,116 and the median family income was $56,560. Males had a median income of $37,182 versus $28,000 for females. The per capita income for the county was $23,654. About 5.30% of families and 7.90% of the population were below the poverty line, including 9.70% of those under age 18 and 6.40% of those age 65 or over.

Government and infrastructure[edit]

The Iowa Department of Corrections Iowa Correctional Institution for Women is in Mitchellville and in Polk County.[13]

In the first third of the 20th century, Polk County was primarily Republican, backing its candidates in all presidential elections from 1896 to 1932 except for 1912 & 1916. From 1936 to 1980, the county was a swing county, only failing to back the national winner during that period in 1960 & 1968. Starting with the 1984 election, the county has become consistently Democratic like many midsize urban counties, backing the party's candidate in every presidential election from that point forward. Following national trends, suburbs of Des Moines such as Urbandale and Ankeny have changed from Republican strongholds into moderate areas; as Iowa shifted dramatically from competitive to firmly Republican during the Donald Trump era in the mid-to-late 2010s, this is one of the state's few remaining Democratic strongholds.

United States presidential election results for Polk County, Iowa[14]
Year Republican Democratic Third party
No.  % No.  % No.  %
2020 106,800 41.27% 146,250 56.52% 5,705 2.20%
2016 93,492 40.38% 119,804 51.74% 18,259 7.89%
2012 96,096 41.98% 128,465 56.13% 4,321 1.89%
2008 89,668 41.82% 120,984 56.43% 3,757 1.75%
2004 95,828 47.29% 105,218 51.93% 1,572 0.78%
2000 79,927 45.89% 89,715 51.51% 4,525 2.60%
1996 60,884 39.00% 83,877 53.73% 11,345 7.27%
1992 63,708 38.09% 78,585 46.98% 24,965 14.93%
1988 57,854 40.42% 84,476 59.01% 814 0.57%
1984 71,413 48.30% 75,413 51.01% 1,022 0.69%
1980 64,156 44.63% 61,984 43.12% 17,618 12.26%
1976 62,316 45.23% 71,917 52.20% 3,530 2.56%
1972 70,245 52.95% 59,169 44.60% 3,245 2.45%
1968 51,814 45.14% 52,731 45.94% 10,239 8.92%
1964 37,280 33.30% 74,194 66.27% 479 0.43%
1960 64,077 53.74% 55,091 46.20% 66 0.06%
1956 62,392 54.02% 53,025 45.91% 74 0.06%
1952 60,934 54.03% 50,867 45.10% 982 0.87%
1948 33,742 41.46% 45,289 55.65% 2,348 2.89%
1944 36,629 44.07% 46,072 55.43% 417 0.50%
1940 41,245 44.26% 51,647 55.42% 301 0.32%
1936 33,819 42.56% 44,274 55.72% 1,367 1.72%
1932 34,023 49.54% 31,517 45.89% 3,132 4.56%
1928 42,290 67.65% 19,725 31.55% 498 0.80%
1924 37,491 62.21% 6,665 11.06% 16,114 26.74%
1920 36,073 66.82% 16,281 30.16% 1,632 3.02%
1916 11,295 45.81% 12,327 50.00% 1,034 4.19%
1912 4,665 20.66% 7,239 32.07% 10,671 47.27%
1908 12,555 58.02% 7,924 36.62% 1,161 5.37%
1904 14,113 72.53% 3,086 15.86% 2,259 11.61%
1900 12,628 64.72% 6,180 31.67% 703 3.60%
1896 11,127 60.24% 7,087 38.37% 257 1.39%
1892 7,757 53.76% 5,538 38.38% 1,133 7.85%
1888 7,049 57.48% 4,966 40.50% 248 2.02%
1884 6,122 56.06% 4,768 43.66% 30 0.27%
1880 4,781 58.50% 2,161 26.44% 1,230 15.05%

Population ranking[edit]

The population ranking of the following table is based on the 2020 census of Polk County.

county seat

Rank City/Town/etc. Municipal type Population (2020 Census) Population (2022 Estimate)
1 Des Moines (partially in Warren County) City 214,133 211,034
2 Ankeny City 67,887 72,222
3 West Des Moines (partially in Dallas, Warren and Madison Counties) City 68,723 70,741
4 Urbandale (partially in Dallas County) City 45,580 46,648
5 Johnston City 24,064 24,390
6 Altoona City 19,565 21,503
7 Clive (partially in Dallas County) City 18,601 18,908
8 Grimes (partially in Dallas County) City 15,392 16,295
9 Norwalk (mostly in Warren County) City 12,799 14,177
10 Pleasant Hill City 10,147 11,186
11 Bondurant City 7,365 8,710
12 Polk City City 5,543 6,046
13 Windsor Heights City 5,252 5,109
14 Carlisle (partially in Warren County) City 4,160 4,283
15 Saylorville CDP 3,584
16 Mitchellville (partially in Jasper County) City 2,485 2,493
17 Granger (mostly in Dallas County) City 1,654 1,951
18 Elkhart City 882 993
19 Runnells City 457 448
20 Alleman City 423 433
21 Sheldahl (partially in Boone and Story Counties) City 297 301

Education[edit]

School districts include:[15]

Attractions[edit]

See also[edit]

References[edit]

  1. ^ a b "State & County QuickFacts". United States Census Bureau. Retrieved December 9, 2023.
  2. ^ "Find a County". National Association of Counties. Archived from the original on March 2, 2011. Retrieved June 7, 2011.
  3. ^ United States Office of Management and Budget. "Update of Statistical Area Definitions and Guidance on Their Uses" (PDF). pp. 5, 36. Archived from the original (PDF) on May 14, 2006. Retrieved July 21, 2006.
  4. ^ The counties were Boone, Clarke, Dallas, Decatur, Jasper, Lucas, Madison, Marshall, Polk, Story, Warren, and Wayne.
  5. ^ The History of Polk County, Iowa: Containing a History of the County, Its Cities, Towns, &c. Union Historical Co. 1880. pp. 419, 425.
  6. ^ Polk County[permanent dead link]
  7. ^ "US Gazetteer files: 2010, 2000, and 1990". United States Census Bureau. February 12, 2011. Retrieved April 23, 2011.
  8. ^ "Annual Estimates of the Resident Population for Counties: April 1, 2020 to July 1, 2022". Retrieved December 9, 2023.
  9. ^ "U.S. Decennial Census". United States Census Bureau. Retrieved July 20, 2014.
  10. ^ "Historical Census Browser". University of Virginia Library. Retrieved July 20, 2014.
  11. ^ "Population of Counties by Decennial Census: 1900 to 1990". United States Census Bureau. Retrieved July 20, 2014.
  12. ^ "Census 2000 PHC-T-4. Ranking Tables for Counties: 1990 and 2000" (PDF). United States Census Bureau. Archived (PDF) from the original on March 27, 2010. Retrieved July 20, 2014.
  13. ^ Iowa Correctional Institution for Women Archived July 22, 2011, at the Wayback Machine. Iowa Department of Corrections. Retrieved November 29, 2010.
  14. ^ Leip, David. "Dave Leip's Atlas of U.S. Presidential Elections". uselectionatlas.org. Retrieved December 8, 2020.
  15. ^ "2020 CENSUS - SCHOOL DISTRICT REFERENCE MAP: Polk County, IA" (PDF). United States Census Bureau. Archived (PDF) from the original on July 20, 2022. Retrieved July 20, 2022. - Text list

External links[edit]

41°41′06″N 93°34′13″W / 41.68500°N 93.57028°W / 41.68500; -93.57028