9,711 people (2024 Census estimate, −1.9% since 2020)
570 square miles of land · 17 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 Calhoun County in the area they serve, reporting 7,968 people served in all (a system that crosses county lines counts its whole population).
| ROCKWELL CITY WATER SUPPLY groundwater · local government · IA1376098 | 2,250 served |
| LAKE CITY WATER SUPPLY groundwater · local government · IA1345043 | 1,731 served |
| MANSON WATER SUPPLY buys groundwater · local government · IA1351027 | 1,727 served |
| POMEROY WATER SUPPLY groundwater · local government · IA1363051 | 671 served |
| LOHRVILLE WATER SUPPLY groundwater · local government · IA1389001 | 381 served |
| FARNHAMVILLE WATER SUPPLY groundwater · local government · IA1320039 | 379 served |
| TWIN LAKES UTILITIES buys groundwater · private · IA1300101 | 300 served |
| LYTTON WATER DEPARTMENT groundwater · local government · IA8133009 | 282 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 Calhoun County's jail, in Vera's latest figure (2019), or 77 per 100,000 residents ages 15–64. In 2014 it was about 4.
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 Calhoun County. School taxes are usually the largest part of a property tax bill.
Spent $14.9 million — $11.9 million to run schools, about $12,957 per student, plus $1.7 million on buildings and equipment. Money in: $7.6 million local (mostly property tax), $6.5 million state, $1.2 million federal. Long-term debt: $3.2 million.
Spent $11.3 million — $9.2 million to run schools, about $11,757 per student, plus $1.1 million on buildings and equipment. Money in: $6.9 million local (mostly property tax), $5 million state, $568,000 federal. Long-term debt: $68,000.
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 Calhoun County about $13.3 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.
198 bridges in Calhoun County: 50 in good condition, 99 fair, and 49 poor (24.7%). “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 LAKE CR. · built 1978 | 359 vehicles a day |
| CO RD N-37 over LAKE CREEK · built 1985 | 354 vehicles a day |
| FM over DD 261 · built 1963 | 300 vehicles a day |
| FM over DD 9-13 · built 1966 | 290 vehicles a day |
| LOCAL over CAMP CK · built 1973 | 279 vehicles a day |
| CO RD over EAST CEDAR CREEK · built 1968 | 220 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $539,017 of work in Calhoun County in fiscal 2025, about $54 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 Calhoun 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 Calhoun County built: brayden.ozark@gmail.com.
More of Iowa: the state government and every county in Iowa.
Nearby counties: Sac County (24 mi) · Webster County (24 mi) · Pocahontas County (24 mi) · Carroll County (26 mi) · Greene County (27 mi) · Buena Vista County (35 mi).