Map of Clark County, Washington

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, first 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-Vancouver-Hillsboro Metropolitan Statistical Area, and is across the Columbia River from Portland, Oregon.

Clark County overview:
Name:	Clark County
FIPS code:	53-011
State:	Washington
Founded:	August 20, 1845 as Vancouver District
Named for:	William Clark on September 3, 1849
Seat:	Vancouver
Largest city:	Vancouver
Total Area:	656 sq mi (1,700 km²)
Land Area:	629 sq mi (1,630 km²)
Total Population:	503,311
Population Density:	770/sq mi (300/km²)

Clark County location map. Where is Clark County?

Clark County location on the U.S. Map. Where is Clark County. — Location of Clark County in the the United States.

Clark County location on the Washington map. Where is Clark County. — Location of Clark County in Washington.

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 for a time.

Clark County Road Map

Clark CountyStreet Map. — Street map of Clark County, Washington. Source: OpenStreetMap (OSM)

Geography

According to the United States Census Bureau, the county has a total area of 656 square miles (1,700 km), of which 629 square miles (1,630 km) is land and 27 square miles (70 km) (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. Eastern and northern Clark County contain forested foothills of the Cascade Mountains, rising to an elevation of 4,000 feet (1,200 m) on the border with Skamania County. Larch Mountain is the county’s highest free-standing peak.

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).

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 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 often swell county waterways, with two of the more destructive floods being those of the Columbia River in June 1894 and May, 1948. The 1948 Memorial Day flood almost topped the Interstate Bridge’s support piers and completely destroyed nearby Vanport, Oregon. Construction of The Dalles Dam and destruction of Celilo Falls are credited with a decrease in 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 70 miles per hour (110 km/h), with other storms including the inauguration day storm of January 20, 1993, the Guadalupe Day storm of December 12, 1995 (with winds up to 95 miles per hour (153 km/h) 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.