132,348 people (2024 Census estimate, +1.0% since 2020)
566 square miles of land · 234 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.
11 active community water systems list Black Hawk County in the area they serve, reporting 160,761 people served in all (a system that crosses county lines counts its whole population).
| WATERLOO WATER WORKS groundwater · local government · IA0790074 | 69,504 served |
| CEDAR FALLS MUNICIPAL WATER UTILITIES groundwater · local government · IA0709084 | 40,713 served |
| IA REGIONAL UTILITIES ASSOC (WAVERLY) groundwater · private · IA0990701 | 37,820 served |
| EVANSDALE WATER WORKS groundwater · local government · IA0723027 | 4,561 served |
| HUDSON WATER SUPPLY buys groundwater · local government · IA0737062 | 2,546 served |
| LA PORTE CITY UTILITIES groundwater · local government · IA0743057 | 2,284 served |
| ELK RUN HEIGHTS WATER SUPPLY buys groundwater · local government · IA0721014 | 1,069 served |
| DUNKERTON MUNI WATER SUPPLY groundwater · local government · IA0717084 | 842 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 258 people were held in Black Hawk County's jail, in Vera's latest figure (2019), or 303 per 100,000 residents ages 15–64. In 2014 it was about 296.
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 Black Hawk County. School taxes are usually the largest part of a property tax bill.
Spent $186.3 million — $154.2 million to run schools, about $14,490 per student, plus $23.4 million on buildings and equipment. Money in: $43.2 million local (mostly property tax), $109.8 million state, $36.9 million federal. Long-term debt: $82.4 million.
Spent $118.4 million — $68.4 million to run schools, about $11,609 per student, plus $43.9 million on buildings and equipment. Money in: $44.5 million local (mostly property tax), $48.3 million state, $5.2 million federal. Long-term debt: $144 million.
Spent $15.3 million — $13.3 million to run schools, about $13,149 per student, plus $1.3 million on buildings and equipment. Money in: $7.7 million local (mostly property tax), $8.3 million state, $875,000 federal. Long-term debt: $4 million.
Spent $12 million — $9.6 million to run schools, about $11,119 per student, plus $1.6 million on buildings and equipment. Money in: $5.1 million local (mostly property tax), $6.1 million state, $801,000 federal. Long-term debt: $4 million.
Spent $6.7 million — $5.3 million to run schools, about $12,906 per student, plus $842,000 on buildings and equipment. Money in: $3.8 million local (mostly property tax), $3.2 million state, $515,000 federal. Long-term debt: $6.5 million.
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 Black Hawk County about $41.8 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.
489 bridges in Black Hawk County: 254 in good condition, 210 fair, and 25 poor (5.1%). “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.
| E RIDGEWAY AVE over DRY RUN CREEK · built 1950 | 8,392 vehicles a day |
| SO MAIN ST RD over S DRY RUN · built 1968 | 6,093 vehicles a day |
| DUBUQUE RD over TRIB TO INDIAN CREEK · built 1957 | 1,532 vehicles a day |
| W RIDGEWAY AVE over S BR DRY RUN · built 1900 | 1,049 vehicles a day |
| HAMMOND AVE over SINK CREEK · built 1900 | 373 vehicles a day |
| E EAGLE RD over MILLER CREEK · built 1965 | 255 vehicles a day |
Source: Federal Highway Administration, National Bridge Inventory (2025 submission). Includes state, county and city bridges.
Federal grants paid for $44.4 million of work in Black Hawk County in fiscal 2025, about $339 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 Black Hawk 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 Black Hawk County built: brayden.ozark@gmail.com.
More of Iowa: the state government and every county in Iowa.
Nearby counties: Bremer County (21 mi) · Buchanan County (24 mi) · Grundy County (25 mi) · Benton County (29 mi) · Tama County (30 mi) · Butler County (30 mi).