13,535 people (2024 Census estimate, −1.4% since 2020)
563 square miles of land · 24 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.
12 active community water systems list Washington County in the area they serve, reporting 21,073 people served in all (a system that crosses county lines counts its whole population).
| WASHINGTON COUNTY WATER COMPANY buys surface water · private · IL1895600 | 12,040 served |
| NASHVILLE surface water · local government · IL1890300 | 3,230 served |
| OKAWVILLE buys surface water · local government · IL1890400 | 1,457 served |
| IRVINGTON buys surface water · local government · IL1890250 | 1,081 served |
| HOYLETON RWC buys surface water · private · IL1895400 | 1,020 served |
| HOYLETON buys surface water · local government · IL1890200 | 658 served |
| ASHLEY buys surface water · local government · IL1890100 | 565 served |
| NEW MINDEN buys surface water · local government · IL1890350 | 343 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 12 people were held in Washington County's jail, in Vera's latest figure (2023), or 145 per 100,000 residents ages 15–64. In 2018 it was about 25.
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.
6 school districts have their office in Washington County. School taxes are usually the largest part of a property tax bill.
Spent $8.8 million — $7.4 million to run schools, about $12,613 per student, plus $481,000 on buildings and equipment. Money in: $4.6 million local (mostly property tax), $4.4 million state, $1.1 million federal. Long-term debt: $1.2 million.
Spent $8.3 million — $7.2 million to run schools, about $13,645 per student, plus $331,000 on buildings and equipment. Money in: $5.8 million local (mostly property tax), $4.9 million state, $1 million federal. Long-term debt: $11.5 million.
Spent $8.9 million — $6.3 million to run schools, about $15,214 per student, plus $378,000 on buildings and equipment. Money in: $3.7 million local (mostly property tax), $5.9 million state, $370,000 federal. Long-term debt: $395,000.
Spent $2.2 million — $1.9 million to run schools, about $15,983 per student, plus $168,000 on buildings and equipment. Money in: $841,000 local (mostly property tax), $1.3 million state, $419,000 federal. Long-term debt: $80,000.
Spent $1.2 million — $1.1 million to run schools, about $15,778 per student, plus $11,000 on buildings and equipment. Money in: $450,000 local (mostly property tax), $586,000 state, $310,000 federal. Long-term debt: $30,000.
Spent $1.1 million — $929,000 to run schools, about $15,483 per student, plus $137,000 on buildings and equipment. Money in: $423,000 local (mostly property tax), $685,000 state, $87,000 federal. Long-term debt: $6,000.
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: Relatively Low compared with other U.S. counties. FEMA estimates natural hazards cost Washington County about $18.4 million a year on average in buildings, crops and lives. Ability to bounce back (community resilience): Very High; social vulnerability: Relatively Moderate.
Source: FEMA National Risk Index (December 2025), expected annual loss. Ratings compare counties nationwide; they're estimates, not predictions.
234 bridges in Washington County: 116 in good condition, 104 fair, and 14 poor (6.0%). “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-64 EB over Prairie Rd Abandoned UPR · built 1972 | 14,000 vehicles a day |
| I-64 WB over Prairie Rd Abandoned UPR · built 1972 | 14,000 vehicles a day |
| ILL 127 over FAI-64 · built 1971 | 10,100 vehicles a day |
| CH 27 over WILLOW CREEK · built 1960 | 625 vehicles a day |
| TR 279 over SOUTH FORK MUD CREEK · built 1925 | 350 vehicles a day |
| CH 7 over BEAUCOUP CREEK · built 1977 | 275 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $4.6 million of work in Washington County in fiscal 2025, about $334 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 Illinois 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 Washington 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 Washington County built: brayden.ozark@gmail.com.
More of Illinois: the state government and every county in Illinois.
Nearby counties: Clinton County (17 mi) · Perry County (19 mi) · Jefferson County (27 mi) · St. Clair County (29 mi) · Randolph County (30 mi) · Marion County (34 mi).