Clayton County, Iowa

Clayton County is a county located in the U.S. state of Iowa. As of the 2020 census, the population was 17,043, and was estimated to be 16,845 in 2025.

History

The county was formed on December 21, 1837, and was named in honor of John M. Clayton, United States Senator from Delaware and later Secretary of State under President Zachary Taylor.

Geography

thumb|150px|right|Route W68 shield

According to the United States Census Bureau, the county has a total area of , of which is land and (0.4%) is water. It is the 5th largest county in Iowa by total area.

Adjacent counties

Allamakee County (north)
Crawford County, Wisconsin (northeast)
Grant County, Wisconsin (east)
Dubuque County (southeast)
Delaware County (south)
Buchanan County (southwest)
Fayette County (west)
Winneshiek County (northwest)

Major highways

x20px U.S. Highway 18
x20px U.S. Highway 52
x20px Iowa Highway 3
x20px Iowa Highway 13
x20px Iowa Highway 56
x20px Iowa Highway 76
x20px Iowa Highway 128

National protected areas

Driftless Area National Wildlife Refuge (part)
Effigy Mounds National Monument (part)
Upper Mississippi River National Wildlife and Fish Refuge (part)

Geology

Clayton County is part of the Driftless Area, a region that completely missed being ice-covered during the last ice age. Streams have deeply carved valleys, while the Mississippi River has spectacular bluffs.

Demographics

thumb|left|2022 US Census [[population pyramid for Clayton County from ACS 5-year estimates]]

2020 census

thumb|right|Population of Clayton County from US census data

As of the 2020 census, the county had a population of 17,043 and a population density of . The median age was 46.7 years; 21.7% of residents were under the age of 18 and 24.2% were 65 years of age or older. For every 100 females there were 102.8 males, and for every 100 females age 18 and over there were 101.5 males age 18 and over.

The racial makeup of the county was 95.2% White, 0.9% Black or African American, 0.3% American Indian and Alaska Native, 0.3% Asian, <0.1% Native Hawaiian and Pacific Islander, 0.8% from some other race, and 2.5% from two or more races. Hispanic or Latino residents of any race comprised 2.0% of the population.

There were 7,315 households in the county, of which 24.2% had children under the age of 18 living in them. Of all households, 52.5% were married-couple households, 20.1% were households with a male householder and no spouse or partner present, and 20.7% were households with a female householder and no spouse or partner present. About 31.3% of all households were made up of individuals and 15.2% had someone living alone who was 65 years of age or older. There were 8,758 housing units, of which 7,315 were occupied, 16.5% were vacant, 77.2% of the occupied units were owner-occupied, and 22.8% were renter-occupied. The homeowner vacancy rate was 2.1% and the rental vacancy rate was 7.5%.

2010 census

The 2010 census recorded a population of 18,130 in the county, with a population density of . There were 8,999 housing units, of which 7,599 were occupied.

2000 census

As of the census of 2000, there were 18,678 people, about 7,500 households, and 1 family residing in the county. The population density was . There were 8,620 housing units at an average density of . The racial makeup of the county was 98.93% White, 0.14% Black or African American, 0.22% Native American, 0.11% Asian, 0.01% Pacific Islander, 0.19% from other races, and 0.41% from two or more races. 0.76% of the population were Hispanic or Latino of any race.

There were 7,375 households, out of which 30.90% had children under the age of 18 living with them, 59.70% were married couples living together, 6.10% had a female householder with no husband present, and 30.40% were non-families. 26.30% of all households were made up of individuals, and 13.30% had someone living alone who was 65 years of age or older. The average household size was 2.47 and the average family size was 2.98.

In the county, the population was spread out, with 25.40% under the age of 18, 6.50% from 18 to 24, 26.00% from 25 to 44, 23.60% from 45 to 64, and 18.50% who were 65 years of age or older. The median age was 40 years. For every 100 females, there were 97.60 males. For every 100 females age 18 and over, there were 95.50 males.

The median income for a household in the county was $34,068, and the median income for a family was $40,199. Males had a median income of $27,165 versus $19,644 for females. The per capita income for the county was $16,930. About 5.70% of families and 8.60% of the population were below the poverty line, including 9.60% of those under age 18 and 9.40% of those age 65 or over.

Communities

Cities

Clayton
Edgewood
Elkader
Elkport
Farmersburg
Garber
Garnavillo
Guttenberg
Luana
Marquette
McGregor
Monona
North Buena Vista
Osterdock
Postville
St. Olaf
Strawberry Point
Volga

Unincorporated communities

Beulah
Ceres
Clayton Center
Communia
Eckards
Fairview
Froelich
Giard
Gunder
Hardin
Highland
Littleport
McGregor Heights
Mederville
Millville
Motor
Osborne
Saint Sebald
Thomasville
Turkey River
Updegraff
Watson
Wood

Townships

Clayton County is divided into these townships:

Boardman
Buena Vista
Cass
Clayton
Cox Creek
Elk
Farmersburg
Garnavillo
Giard
Grand Meadow
Highland
Jefferson
Lodomillo
Mallory
Marion
Mendon
Millville
Monona
Read
Sperry
Volga
Wagner

Population ranking

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

† county seat

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! Rank

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