21,039 people (2024 Census estimate, +2.1% since 2020)
1,925 square miles of land · 11 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.
30 active community water systems list Adams County in the area they serve, reporting 15,781 people served in all (a system that crosses county lines counts its whole population).
| OTHELLO WATER DEPARTMENT groundwater · local government · WA5364850 | 8,755 served |
| RITZVILLE WATER DEPARTMENT groundwater · local government · WA5372700 | 1,725 served |
| LIND TOWN OF groundwater · local government · WA5347350 | 903 served |
| ADAMS COUNTY WATER DIST #1 buys groundwater · local government · WA5322525 | 870 served |
| OTHELLO MANOR LLC groundwater · private · WA5364845 | 400 served |
| GOLDEN PLAINS MHP #1 groundwater · private · WA5389060 | 360 served |
| WASHTUCNA WATER DEPARTMENT groundwater · local government · WA5393450 | 250 served |
| SUMMERSET WEST WATER ASSOCIATION groundwater · private · WA5385080 | 240 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 23 people were held in Adams County's jail, in Vera's latest figure (2021), or 190 per 100,000 residents ages 15–64. In 2016 it was about 21.
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.
5 school districts have their office in Adams County. School taxes are usually the largest part of a property tax bill.
Spent $80.6 million — $77.3 million to run schools, about $16,260 per student, plus $1.7 million on buildings and equipment. Money in: $6.6 million local (mostly property tax), $64.4 million state, $13.5 million federal. Long-term debt: $13.4 million.
Spent $7.2 million — $6.6 million to run schools, about $18,296 per student, plus $164,000 on buildings and equipment. Money in: $2.6 million local (mostly property tax), $4.8 million state, $667,000 federal. Long-term debt: $8.1 million.
Spent $6.5 million — $6.1 million to run schools, about $27,900 per student, plus $309,000 on buildings and equipment. Money in: $1.4 million local (mostly property tax), $4.8 million state, $614,000 federal. Long-term debt: $1.9 million.
Spent $2.8 million — $2.8 million to run schools, about $38,342 per student, plus $11,000 on buildings and equipment. Money in: $278,000 local (mostly property tax), $2.4 million state, $195,000 federal.
Spent $469,000 — $469,000 to run schools, about $93,800 per student. Money in: $102,000 local (mostly property tax), $425,000 state, $34,000 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 Adams County about $7.4 million a year on average in buildings, crops and lives. Ability to bounce back (community resilience): Very Low; social vulnerability: Relatively Moderate.
Source: FEMA National Risk Index (December 2025), expected annual loss. Ratings compare counties nationwide; they're estimates, not predictions.
187 bridges in Adams County: 65 in good condition, 99 fair, and 23 poor (12.3%). “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.
| I-90 over BNSF RAILROAD · built 1968 | 10,667 vehicles a day |
| I-90 over BNSF RAILROAD · built 1968 | 10,667 vehicles a day |
| I-90 over SR 261 · built 1958 | 8,405 vehicles a day |
| I-90 over DAMON RD · built 1972 | 6,018 vehicles a day |
| I-90 over WAHL RD · built 1972 | 6,000 vehicles a day |
| I-90 over N PAHA PACKARD RD · built 1972 | 5,950 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $36.1 million of work in Adams County in fiscal 2025, about $1,753 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 Adams 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 Adams County built: brayden.ozark@gmail.com.
More of Washington: the state government and every county in Washington.
Nearby counties: Franklin County (38 mi) · Lincoln County (40 mi) · Whitman County (47 mi) · Grant County (47 mi) · Walla Walla County (52 mi) · Columbia County (57 mi).