56,343 people (2024 Census estimate, +7.1% since 2020)
570 square miles of land · 99 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.
14 active community water systems list Warren County in the area they serve, reporting 57,488 people served in all (a system that crosses county lines counts its whole population).
| WARREN WATER DISTRICT buys surface water · private · IA9133701 | 20,095 served |
| INDIANOLA WATER SUPPLY groundwater · local government · IA9133075 | 15,833 served |
| NORWALK WATER SUPPLY buys surface water · local government · IA9164078 | 14,334 served |
| CARLISLE WATER SUPPLY groundwater · local government · IA9113071 | 4,170 served |
| MILO PUBLIC WATER SUPPLY buys surface water · local government · IA9155083 | 788 served |
| NEW VIRGINIA WATER SUPPLY buys surface water · local government · IA9159067 | 498 served |
| MARTENSDALE WATER SUPPLY buys surface water · local government · IA9147047 | 421 served |
| LACONA WATER SUPPLY buys groundwater · local government · IA9138041 | 361 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 5 people were held in Warren County's jail, in Vera's latest figure (2018), or 15 per 100,000 residents ages 15–64. In 2013 it was about 22.
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 Warren County. School taxes are usually the largest part of a property tax bill.
Spent $52.3 million — $43.3 million to run schools, about $11,822 per student, plus $6.1 million on buildings and equipment. Money in: $26.4 million local (mostly property tax), $31.6 million state, $4.2 million federal. Long-term debt: $36.4 million.
Spent $52.7 million — $40.3 million to run schools, about $11,287 per student, plus $9.3 million on buildings and equipment. Money in: $21 million local (mostly property tax), $32.3 million state, $2.4 million federal. Long-term debt: $73.5 million.
Spent $29.7 million — $26.6 million to run schools, about $11,218 per student, plus $1.8 million on buildings and equipment. Money in: $12.3 million local (mostly property tax), $19.3 million state, $1.9 million federal. Long-term debt: $23.9 million.
Spent $8.2 million — $6.8 million to run schools, about $11,752 per student, plus $282,000 on buildings and equipment. Money in: $5 million local (mostly property tax), $4 million state, $418,000 federal. Long-term debt: $2 million.
Spent $9.6 million — $7.2 million to run schools, about $15,912 per student, plus $1.3 million on buildings and equipment. Money in: $3.7 million local (mostly property tax), $5 million state, $567,000 federal. Long-term debt: $611,000.
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: Very Low compared with other U.S. counties. FEMA estimates natural hazards cost Warren County about $18.7 million a year on average in buildings, crops and lives. Ability to bounce back (community resilience): Very High; social vulnerability: Very Low.
Source: FEMA National Risk Index (December 2025), expected annual loss. Ratings compare counties nationwide; they're estimates, not predictions.
238 bridges in Warren County: 102 in good condition, 88 fair, and 48 poor (20.2%). “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.
| FM over NORTH RIVER · built 1960 | 1,714 vehicles a day |
| G-58 over OTTER CREEK · built 1951 | 996 vehicles a day |
| FM over BUTCHER CREEK · built 1952 | 830 vehicles a day |
| FM over S RIVER · built 1949 | 807 vehicles a day |
| FM over SHORT CREEK · built 1968 | 717 vehicles a day |
| W MAIN ST over SMALL NATURAL STREAM · built 1959 | 643 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $14 million of work in Warren County in fiscal 2025, about $267 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 Iowa 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 Warren 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 Warren County built: brayden.ozark@gmail.com.
More of Iowa: the state government and every county in Iowa.
Nearby counties: Madison County (23 mi) · Clarke County (24 mi) · Lucas County (24 mi) · Polk County (24 mi) · Marion County (25 mi) · Dallas County (35 mi).