4,025 people (2024 Census estimate, +1.8% since 2020)
869 square miles of land · 5 people per square mile
“Highest” and “lowest” are just order, not grades: a high rank for poverty or hazard losses means more of it. Each figure's source is in its section below.
2 active community water systems list Columbia County in the area they serve, reporting 3,521 people served in all (a system that crosses county lines counts its whole population).
| DAYTON WATER DEPARTMENT groundwater · local government · WA5318250 | 3,374 served |
| STARBUCK CITY OF groundwater · local government · WA5383750 | 147 served |
Source: U.S. EPA Safe Drinking Water Information System (SDWIS), active community systems, . Look up any system's violations and test results with EPA's search using its ID.
About 3 people were held in Columbia County's jail, in Vera's latest figure (2021), or 131 per 100,000 residents ages 15–64. In 2016 it was about 6.
Source: Vera Institute of Justice, Incarceration Trends (built from federal Bureau of Justice Statistics jail surveys). Counties without their own jail, or that share one, may show no figure.
2 school districts have their office in Columbia County. School taxes are usually the largest part of a property tax bill.
Spent $9.1 million — $7.7 million to run schools, about $19,595 per student, plus $701,000 on buildings and equipment. Money in: $1.8 million local (mostly property tax), $5.6 million state, $1.4 million federal.
Spent $5.6 million — $5.6 million to run schools, about $30,086 per student, plus $21,000 on buildings and equipment. Money in: $51,000 local (mostly property tax), $5.7 million state, $250,000 federal.
Source: U.S. Census Bureau, 2023 Annual Survey of School System Finances. Districts are listed by the county of their main office; some serve neighboring counties too.
Source: County Health Rankings & Roadmaps 2025 (University of Wisconsin Population Health Institute), which gathers federal data (CDC, Census, and others); measures cover different recent years. Blank lines aren't reported for small counties.
Overall risk: Very Low compared with other U.S. counties. FEMA estimates natural hazards cost Columbia County about $3.9 million a year on average in buildings, crops and lives. Ability to bounce back (community resilience): Relatively Moderate; social vulnerability: Relatively Moderate.
Source: FEMA National Risk Index (December 2025), expected annual loss. Ratings compare counties nationwide; they're estimates, not predictions.
86 bridges in Columbia County: 38 in good condition, 39 fair, and 9 poor (10.5%). “Poor” means a main part — the deck, the beams, or the supports — is rated 4 or lower on the federal 0–9 scale. It doesn't mean unsafe to drive; unsafe bridges are closed.
| US 12 over WAREHOUSE YARD · built 1933 | 2,442 vehicles a day |
| US 12 over TUCANNON RIVER · built 1967 | 1,884 vehicles a day |
| SR 261 over SNAKE RIVER · built 1927 | 485 vehicles a day |
| KELLOG HOLLOW RD. over TUCANNON RIVER · built 1962 | 350 vehicles a day |
| TUCANNON ROAD over TUCANNON RIVER · built 1968 | 200 vehicles a day |
| ROSE GULCH ROAD over TOUCHET RIVER · built 1963 | 150 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $3.2 million of work in Columbia County in fiscal 2025, about $799 per resident — to the county, cities, schools, hospitals, nonprofits and others.
Source: USAspending.gov, grants by place of performance, fiscal 2025 (Oct. 2024 to Sept. 2025). Search it by county to see each award.
From Grants.gov: posted grants listing county governments as eligible, soonest deadline first; research-only and overseas programs left out; list updated 2026-10-13, refreshed weekly. 62 are open in all. Cities, towns, school districts and nonprofits have their own lists there.
Registration deadlines, early voting and polling places for Washington are on the federal site vote.gov, which links to the state's official election office.
The budget, property tax rates, audits, local officials and offices for Columbia County come from the county's own records, which we haven't gathered — not gathered, never hidden. See what a full county site looks like, or ask to have Columbia County built: brayden.ozark@gmail.com.
More of Washington: the state government and every county in Washington.
Nearby counties: Garfield County (20 mi) · Walla Walla County (27 mi) · Asotin County (33 mi) · Whitman County (46 mi) · Franklin County (50 mi) · Nez Perce County, ID (55 mi).