| Rock Island County, Illinois | |
|---|---|
Rock Island County Courthouse
|
|
Location in the U.S. state of Illinois |
|
Illinois's location in the U.S. |
|
| Founded | 1831 |
| Seat | Rock Island |
| Largest city | Moline |
| Area | |
| • Total | 451 sq mi (1,168 km2) |
| • Land | 428 sq mi (1,109 km2) |
| • Water | 24 sq mi (62 km2), 5.2% |
| Population | |
| • (2010) | 147,546 |
| • Density | 345/sq mi (133/km²) |
| Congressional district | 17th |
| Time zone | Central: UTC-6/-5 |
| Website | www |
Rock Island County is a county located in the U.S. state of Illinois, bounded on the west by the Mississippi River. According to the 2010 census, it had a population of 147,546.[1] Its county seat is Rock Island; its largest city is neighboring Moline.[2]
Rock Island County is one of the four counties that make up the Davenport-Moline-Rock Island, IA-IL Metropolitan Statistical Area.[3]
Rock Island County was formed in 1831 out of Jo Daviess County. It was named for Rock Island, an island in the Mississippi River now known as Arsenal Island.[4]
According to the U.S. Census Bureau, the county has a total area of 451 square miles (1,170 km2), of which 428 square miles (1,110 km2) is land and 24 square miles (62 km2) (5.2%) is water.[5]
| Rock Island, Illinois | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Climate chart (explanation) | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
In recent years, average temperatures in the county seat of Rock Island have ranged from a low of 13 °F (−11 °C) in January to a high of 85 °F (29 °C) in July, although a record low of −22 °F (−30 °C) was recorded in February 1996 and a record high of 103 °F (39 °C) was recorded in July 2006. Average monthly precipitation ranged from 1.28 inches (33 mm) in January to 4.75 inches (121 mm) in June.[6]
| Historical population | |||
|---|---|---|---|
| Census | Pop. | %± | |
| 1840 | 2,610 | — | |
| 1850 | 6,937 | 165.8% | |
| 1860 | 21,005 | 202.8% | |
| 1870 | 29,783 | 41.8% | |
| 1880 | 38,302 | 28.6% | |
| 1890 | 41,917 | 9.4% | |
| 1900 | 55,249 | 31.8% | |
| 1910 | 70,404 | 27.4% | |
| 1920 | 92,297 | 31.1% | |
| 1930 | 98,191 | 6.4% | |
| 1940 | 113,323 | 15.4% | |
| 1950 | 133,558 | 17.9% | |
| 1960 | 150,991 | 13.1% | |
| 1970 | 166,734 | 10.4% | |
| 1980 | 165,968 | −0.5% | |
| 1990 | 148,723 | −10.4% | |
| 2000 | 149,374 | 0.4% | |
| 2010 | 147,546 | −1.2% | |
| Est. 2016 | 144,784 | [7] | −1.9% |
| U.S. Decennial Census[8] 1790-1960[9] 1900-1990[10] 1990-2000[11] 2010-2013[1] |
|||
As of the 2010 United States Census, there were 147,546 people, 61,303 households, and 38,384 families residing in the county.[12] The population density was 345.0 inhabitants per square mile (133.2/km2). There were 65,756 housing units at an average density of 153.8 per square mile (59.4/km2).[5] The racial makeup of the county was 81.6% white, 9.0% black or African American, 1.6% Asian, 0.3% American Indian, 4.4% from other races, and 3.0% from two or more races. Those of Hispanic or Latino origin made up 11.6% of the population.[12] In terms of ancestry, 25.9% were German, 14.2% were Irish, 8.7% were English, 6.8% were Swedish, and 5.2% were American.[13]
Of the 61,303 households, 29.0% had children under the age of 18 living with them, 45.3% were married couples living together, 12.7% had a female householder with no husband present, 37.4% were non-families, and 31.6% of all households were made up of individuals. The average household size was 2.34 and the average family size was 2.93. The median age was 40.0 years.[12]
The median income for a household in the county was $46,226 and the median income for a family was $58,962. Males had a median income of $42,548 versus $31,917 for females. The per capita income for the county was $25,071. About 8.7% of families and 12.3% of the population were below the poverty line, including 19.0% of those under age 18 and 7.1% of those age 65 or over.[14]
At one time Mississippi Valley Airlines had its headquarters in Quad City Airport in the county.[15] John Deere is headquartered in Moline.
Rock Island County is divided into eighteen townships:
| Year | Republican | Democratic | Third Parties |
|---|---|---|---|
| 2016 | 42.2% 26,998 | 50.5% 32,298 | 7.3% 4,698 |
| 2012 | 38.2% 24,934 | 60.0% 39,157 | 1.7% 1,126 |
| 2008 | 37.0% 25,364 | 61.5% 42,210 | 1.5% 1,034 |
| 2004 | 42.4% 29,663 | 57.0% 39,880 | 0.6% 429 |
| 2000 | 38.7% 25,194 | 58.3% 37,957 | 3.0% 1,944 |
| 1996 | 33.8% 20,626 | 57.1% 34,822 | 9.0% 5,507 |
| 1992 | 32.2% 23,212 | 51.9% 37,412 | 15.9% 11,415 |
| 1988 | 40.4% 27,412 | 59.2% 40,174 | 0.5% 315 |
| 1984 | 46.4% 35,121 | 53.1% 40,208 | 0.5% 343 |
| 1980 | 48.5% 34,788 | 41.9% 30,045 | 9.7% 6,942 |
| 1976 | 47.7% 34,007 | 50.5% 35,994 | 1.8% 1,260 |
| 1972 | 53.4% 37,548 | 46.3% 32,529 | 0.4% 253 |
| 1968 | 43.4% 30,404 | 49.2% 34,506 | 7.5% 5,230 |
| 1964 | 36.2% 23,714 | 63.8% 41,759 | 0.0% 0 |
| 1960 | 49.0% 32,534 | 50.9% 33,812 | 0.2% 108 |
| 1956 | 51.7% 31,342 | 48.1% 29,145 | 0.2% 118 |
| 1952 | 54.1% 32,933 | 45.8% 27,879 | 0.2% 100 |
| 1948 | 47.0% 22,192 | 52.0% 24,542 | 1.0% 477 |
| 1944 | 44.2% 23,980 | 55.5% 30,102 | 0.3% 180 |
| 1940 | 42.0% 25,629 | 57.7% 35,240 | 0.4% 232 |
| 1936 | 36.8% 19,487 | 61.7% 32,741 | 1.5% 799 |
| 1932 | 45.6% 21,205 | 53.0% 24,676 | 1.4% 668 |
| 1928 | 65.2% 27,246 | 34.3% 14,334 | 0.5% 196 |
| 1924 | 57.7% 20,563 | 10.2% 3,631 | 32.1% 11,453 |
| 1920 | 71.3% 21,908 | 17.0% 5,208 | 11.7% 3,603 |
| 1916 | 53.2% 16,169 | 35.9% 10,914 | 10.9% 3,327 |
| 1912 | 42.6% 6,506 | 26.1% 3,997 | 31.3% 4,786 |
| 1908 | 55.5% 8,196 | 32.1% 4,739 | 12.5% 1,846 |
| 1904 | 61.7% 8,152 | 16.3% 2,156 | 21.9% 2,895 |
| 1900 | 61.2% 8,299 | 35.3% 4,786 | 3.5% 471 |
| 1896 | 60.1% 7,323 | 38.5% 4,692 | 1.4% 176 |
| 1892 | 52.4% 5,052 | 41.8% 4,034 | 5.8% 559 |