Pierce County | |
|---|---|
 Old City Hall in Tacoma. | |
 Flag  Seal | |
 Location within the U.S. state of Washington | |
 Washington's location within the U.S. | |
| Coordinates: 47°03′N 122°07′W / 47.05°N 122.11°W | |
| Country |  United States |
| State |  Washington |
| Founded | December 22, 1852 |
| Named for | Franklin Pierce |
| Seat | Tacoma |
| Largest city | Tacoma |
| Area | |
• Total | 1,806 sq mi (4,680 km2) |
| • Land | 1,670 sq mi (4,300 km2) |
| • Water | 137 sq mi (350 km2) 7.6% |
| Population (2020) | |
• Total | 921,130 |
• Estimate (2023) | 928,696  |
| • Density | 510/sq mi (200/km2) |
| Time zone | UTC−8 (Pacific) |
| • Summer (DST) | UTC−7 (PDT) |
| Congressional districts | 6th, 8th, 10th |
| Website | piercecountywa |
Pierce County is a county in the U.S. state of Washington. As of the 2020 census, the population was 921,130,[1] up from 795,225 in 2010, making it the second-most populous county in Washington, behind King County, and the 59th-most populous in the United States. The county seat and largest city is Tacoma.[2] Formed out of Thurston County on December 22, 1852, by the legislature of Oregon Territory,[3][4] it was named for U.S. President Franklin Pierce. Pierce County is in the Seattle metropolitan area (formally the Seattle-Tacoma-Bellevue, WA, metropolitan statistical area).
Pierce County is home to the volcano Mount Rainier, the tallest mountain in the Cascade Range. Its most recent recorded eruption was between 1820 and 1854. There is no imminent risk of eruption, but geologists expect that the volcano will erupt again. If this should happen, parts of Pierce County and the Puyallup Valley would be at risk from lahars, lava, or pyroclastic flows. The Mount Rainier Volcano Lahar Warning System was established in 1998 to assist in the evacuation of the Puyallup River valley in case of eruption.
- ^ "State & County QuickFacts". United States Census Bureau. Retrieved March 20, 2024.
- ^ "Find a County". National Association of Counties. Retrieved June 7, 2011.
- ^ Reinartz, Kay. "History of King County Government 1853–2002" (PDF). Archived from the original (PDF) on December 1, 2007. Retrieved December 29, 2007.
- ^ "Milestones for Washington State History — Part 2: 1851 to 1900". HistoryLink.org. March 6, 2003.