Clark County is the southernmost county in the U.S. state of Washington. As of the 2020 census, the population was 503,311, making it Washington's fifth-most populous county. Its county seat and largest city is Vancouver. It was the first county in Washington, originally named Vancouver County in 1845 before being renamed for William Clark of the Lewis and Clark Expedition in 1849. It was created by the Provisional Government of Oregon in Oregon Country on August 20, 1845, and at that time covered the entire present-day state. Clark County is the third-most-populous county in the Portland metropolitan area, and is across the Columbia River from Portland, Oregon.
History Clark County was created on August 20, 1845, as Vancouver District, named for its town, following the removal of the area from three other districts on July 27, 1844. It included all the land north of the Columbia River, west of the Rocky Mountains, and south of Alaska. On December 21, 1845, the provisional government changed its name to Vancouver County. At that time it stretched from the Columbia River to 54 degrees 40 minutes North Latitude in what is now British Columbia, Canada. On June 15, 1846, the United States Senate approved the present boundary between the U.S. and Canada at the 49th parallel.
On August 13, 1848, President James K. Polk signed an act creating the entire region as the Oregon Territory. On September 3, 1849, the Oregon Territorial Legislature modified the borders again and changed its name to Clarke County in honor of explorer William Clark. At this time it included all of present-day Washington and continued to be divided and subdivided until reaching its present area in 1880. It was not until 1925 that the spelling was corrected to its present form.
In September 1902 the Yacolt Burn, the largest fire in state history, began in neighboring Skamania County and swept west along a 12-mile front to Yacolt, nearly engulfing the town. Salvaging the remaining timber was a lucrative industry until 1924.
Geography
According to the United States Census Bureau, the county has a total area of , of which is land and (4.1%) is water. It is the fifth-smallest county in Washington by land area.
Clark County is surrounded on two sides by the Columbia River and on the north by the North Fork of the Lewis River. The East Fork of the Lewis River and the Washougal River cut across the county. The largest stream arising solely within the county is Salmon Creek, which terminates at Vancouver Lake before eventually flowing into the Columbia River.
Like most of Oregon and Washington south of Puget Sound into the Willamette Valley the landscape and climate of Clark County are determined by its placement between the volcanic Pacific Coast and Cascade Ranges, where glaciation helped form a U-shaped valley which meets the river valley of the Columbia River as it leaves the Columbia River Gorge. Volcanic andisol soils are common, with fertile mollisols in the lower areas. The central and southwest areas of the county are generally flat floodplains, sculpted by torrents of prehistoric Lake Missoula. A series of dramatic floods known as the Missoula Floods took place 15,000–13,000 years ago, as several ice dams melted, forming a series of low steps such as the "Heights", "Mill Plain", "Fourth Plain" and "Fifth Plain". Clark County's Köppen climate classification is "Csb".
Many lakes border the river in the lowlands near Ridgefield, including Vancouver Lake. The eastern and northern parts of Clark County contain forested foothills of the Cascade Mountains, rising to an elevation of 4,000 feet (1,200 m) along the border with Skamania County. Larch Mountain is the county’s highest freestanding peak.
Mount Hood, Mount St. Helens and Mount Adams are all visible from Clark County, and cold winter winds through the Columbia River Gorge often bring freezing rain and a coating of glaze ice or clear ice is sometimes known locally as a "silver thaw", especially in southeastern areas of the county closest to the gorge. The counterpart to this are warm winds from the southwest known locally as the "Pineapple Express".
Climate
Spring thaws can swell county waterways, and two of the most destructive floods were those of the Columbia River in June 1894 and May 1948. The 1948 Memorial Day flood nearly reached the Interstate Bridge’s support piers and completely destroyed nearby Vanport, Oregon. Construction of The Dalles Dam and the destruction of Celilo Falls are credited with reducing the severity of such floods.
Significant windstorms in Clark County include the Columbus Day windstorm of October 12, 1962, and an April 6, 1972, tornado which rated F3 on the Fujita scale, striking a local school. A "Friday the 13th" storm in November 1981 brought winds up to , with other storms including the inauguration day storm of January 20, 1993, the Guadalupe Day storm of December 12, 1995 (with winds up to at Washougal, Washington) and small tornado on January 10, 2008, which destroyed a boathouse at Vancouver Lake and caused damage to buildings in Hazel Dell before dissolving near Hockinson."Region has long history of damaging windstorms," by Don Hamilton, The Columbian, January 11, 2008, p. A5.
Ecology Flora and fauna of the region include the normal ecological succession from lowland big leaf maple and western red cedar through Garry oak on up through fire-dependent species such as lodgepole pine and Douglas fir, as well as grand fir, silver fir and other species common to Gifford Pinchot National Forest. In addition to a wide variety of birds including great blue heron, raptors such as barred owl, osprey, red-tailed hawk and bald eagle, corvids (raven, crow, California scrub and Steller's jay) and others, the native streams are home to various species of salmon and the Vancouver Trout Hatchery. Larger mammals include black-tailed deer, coyote, raccoon, skunk and invasive opossum; with sightings of lynx, bobcat, black bear, cougar and elk not uncommon, especially in the northern parts of the county. Common foods used by the indigenous people such as the Klickitat tribe and Chinook included salmon, huckleberry and Camassia quamash (after which the city of Camas, Washington is named).
Geographic features
Cascade Mountains Columbia River Vancouver Lake East Fork Lewis River Lacamas Creek Lacamas Lake Battle Ground Lake Moulton Falls Lucia Falls Larch Mountain Silver Star Mountain Green Mountain Lewisville Park Daybreak Park Vancouver Lake Park Klineline Park
Major highways Interstate 5 Interstate 205 State Route 14 State Route 500 State Route 501 State Route 502 State Route 503
Former major highway U.S. Route 99 U.S. Route 830 State Route 120 State Route 140
Adjacent counties Cowlitz County - north Skamania County - east Multnomah County, Oregon - south Columbia County, Oregon - southwest
National protected areas Fort Vancouver National Historic Site (part) Gifford Pinchot National Forest (part) Ridgefield National Wildlife Refuge Steigerwald Lake National Wildlife Refuge
Economy
Clark County's largest industries include health care, professional and business services, and retail. In 2019, approximately 65,000 Clark County residents commuted to work in Portland, Oregon; approximately 17,000 residents from Oregon commuted to work in Clark County. Although Washington does not have a state income tax, residents who worked in Oregon were required to pay income tax to that state for earnings in Oregon. Clark County residents also cross the Columbia River to shop without sales taxes, which Oregon also lacks; this phenomenon caused up to $5.9 million in estimated lost sales tax revenue for the county government in 2022. Data collected by the Oregon Office of Economic Analysis indicated that nearly 14,000 residents moved to Clark County from Portland in 2022.
Demographics
Racial and ethnic composition +Clark County, Washington – Racial and ethnic compositionRace / Ethnicity (NH = Non-Hispanic)Pop 1980Pop 1990Pop 2000Pop 2010 Pop 2020% 1980% 1990% 2000% 2010% 2020White alone (NH)182,923221,552299,134347,793366,72795.16%93.07%86.65%81.76%72.86%Black or African American alone (NH)1,6702,8735,6288,02510,8500.87%1.21%1.63%1.89%2.16%Native American or Alaska Native alone (NH)1,5212,1292,5752,9703,0510.79%0.89%0.75%0.70%0.61%Asian alone (NH)2,2945,47810,99317,27623,9101.19%2.30%3.18%4.06%4.75%Native Hawaiian or Pacific Islander alone (NH)x included in the Asian category in the 1980 Censusx included in the Asian category in the 1990 Census1,2252,5895,127xx0.35%0.61%1.02%Other race alone (NH)7601494756392,5360.40%0.06%0.14%0.15%0.50%Mixed race or Multiracial (NH)x not an option in the 1980 Censusx not an option in the 1990 Census8,96013,90532,320xx2.60%3.27%6.42%Hispanic or Latino (any race)3,0595,87216,24832,16658,7901.59%2.47%4.71%7.56%11.68%Total192,227238,053345,238425,363503,311 100.00%100.00%100.00%100.00%100.00%
2020 census As of the 2020 census, there were 503,311 people, 187,188 households, and 195,036 housing units in the county.
The population density was .
The racial makeup (including Hispanics in the racial counts) of the county was 75.5% White, 2.3% Black or African American, 1.0% American Indian and Alaska Native, 4.8% Asian, 5.0% from some other race, and 10.4% from two or more races. Hispanic or Latino residents of any race comprised 11.7% of the population.
Of the residents, 23.3% were under the age of 18, 5.6% were under 5, and 16.4% were 65 years of age or older; the median age was 38.8 years. For every 100 females there were 97.6 males, and for every 100 females age 18 and over there were 95.6 males. 86.5% of residents lived in urban areas and 13.5% lived in rural areas.
The average household size was 2.67 people per household. Of the 187,188 households, 32.4% had children under the age of 18 living with them and 23.5% had a female householder with no spouse or partner present. About 23.1% of all households were made up of individuals and 10.0% had someone living alone who was 65 years of age or older.
There were 195,036 housing units, of which 4.0% were vacant. Among occupied housing units, 64.8% were owner-occupied and 35.2% were renter-occupied. The homeowner vacancy rate was 0.9% and the rental vacancy rate was 5.1%. Reports indicate that approximately 8,200 individuals experiences homelessness in the county in 2025.
2010 census As of the 2010 census, there were 425,363 people, 158,099 households, and 110,672 families residing in the county. The population density was . There were 167,413 housing units at an average density of . The racial makeup of the county was 85.4% white, 4.1% Asian, 2.0% black or African American, 0.9% American Indian, 0.6% Pacific islander, 2.9% from other races, and 4.0% from two or more races. Those of Hispanic or Latino origin made up 7.6% of the population. In terms of ancestry, 24.4% were German, 13.1% were Irish, 13.1% were English, 5.7% were Norwegian, and 4.3% were American.
Of the 158,099 households, 36.3% had children under the age of 18 living with them, 53.6% were married couples living together, 11.3% had a female householder with no husband present, 30.0% were non-families, and 23.1% of all households were made up of individuals. The average household size was 2.67 and the average family size was 3.15. The median age was 36.7 years.
The median income for a household in the county was $58,262 and the median income for a family was $67,352. Males had a median income of $52,160 versus $38,167 for females. The per capita income for the county was $27,828. About 7.8% of families and 10.9% of the population were below the poverty line, including 14.9% of those under age 18 and 7.2% of those age 65 or over.
2000 census