Washington State Sheriffs' Association
Home Page Contact WSSA WSSA Officers County Information Links of Interest

Columbia County

Founded: November 11, 1875

Columbia County
Sheriff's Office

341 East Main Street
Dayton, WA 99328

Phone: 509.382.1100
Web Site
Send Email

Columbia County is named after the Columbia River. It is part of the Palouse, a wide and rolling prairie-like region of the middle Columbia basin. The county seat is at Dayton, which is also the county's largest city. As of 2017, the estimated population was 4,047.

Columbia County was created out of Walla Walla County on November 11, 1875.

According to the U.S. Census Bureau, the county has a total area of 874 square miles, of which, 869 square miles of it is land and 5 square miles of it (0.54%) is water. The population density is 5 per square mile.

Principal Communities:
  • Dayton (County Seat)
  • Starbuck

Previous Page


Sheriff Joe Helm
Took Office: January 1, 2019

Employees: 15
Budget: $986 thousand

Columbia County Courthouse
County Seat: