20,407 people (2024 Census estimate, −1.6% since 2020)
569 square miles of land · 36 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.
13 active community water systems list Carroll County in the area they serve, reporting 19,877 people served in all (a system that crosses county lines counts its whole population).
| CARROLL MUNICIPAL WATER SUPPLY groundwater · local government · IA1415072 | 10,321 served |
| WEST CENTRAL RWA - NISH SYSTEM groundwater · private · IA1400902 | 3,573 served |
| MANNING WATER SUPPLY groundwater · local government · IA1457025 | 1,392 served |
| COON RAPIDS MUNICIPAL UTILITIES groundwater · local government · IA1427070 | 1,242 served |
| GLIDDEN WATER SUPPLY groundwater · local government · IA1438091 | 1,140 served |
| ARCADIA WATER SUPPLY buys groundwater · local government · IA1403062 | 525 served |
| BREDA WATER SUPPLY groundwater · local government · IA1409041 | 502 served |
| TEMPLETON WATER SUPPLY buys groundwater · local government · IA1479015 | 352 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 10 people were held in Carroll County's jail, in Vera's latest figure (2019), or 81 per 100,000 residents ages 15–64. In 2014 it was about 11.
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.
4 school districts have their office in Carroll County. School taxes are usually the largest part of a property tax bill.
Spent $26.5 million — $24 million to run schools, about $13,313 per student, plus $1.1 million on buildings and equipment. Money in: $13.7 million local (mostly property tax), $13.3 million state, $2.8 million federal. Long-term debt: $7.1 million.
Spent $12.1 million — $10 million to run schools, about $14,038 per student, plus $1.5 million on buildings and equipment. Money in: $5.9 million local (mostly property tax), $5.5 million state, $1 million federal. Long-term debt: $773,000.
Spent $7.9 million — $5.5 million to run schools, about $12,502 per student, plus $2 million on buildings and equipment. Money in: $3.3 million local (mostly property tax), $3.8 million state, $747,000 federal. Long-term debt: $1.3 million.
Spent $5.7 million — $5.1 million to run schools, about $13,337 per student, plus $297,000 on buildings and equipment. Money in: $3 million local (mostly property tax), $2.1 million state, $492,000 federal. Long-term debt: $442,000.
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 Carroll County about $22.7 million a year on average in buildings, crops and lives. Ability to bounce back (community resilience): Very High; social vulnerability: Relatively Low.
Source: FEMA National Risk Index (December 2025), expected annual loss. Ratings compare counties nationwide; they're estimates, not predictions.
249 bridges in Carroll County: 120 in good condition, 112 fair, and 17 poor (6.8%). “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 BRUSHY FORK CREEK · built 1964 | 650 vehicles a day |
| EAST ST over WILLOW CREEK · built 1964 | 580 vehicles a day |
| FM over CREEK · built 1939 | 399 vehicles a day |
| LOCAL over STREAM · built 1970 | 120 vehicles a day |
| LOCAL over BRUSHY FORK CREEK · built 1925 | 60 vehicles a day |
| E35 (200TH ST) over FIELD STREAM · built 1946 | 60 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $7.8 million of work in Carroll County in fiscal 2025, about $374 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 Carroll 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 Carroll County built: brayden.ozark@gmail.com.
More of Iowa: the state government and every county in Iowa.
Nearby counties: Greene County (25 mi) · Audubon County (25 mi) · Calhoun County (27 mi) · Crawford County (27 mi) · Sac County (27 mi) · Guthrie County (31 mi).