Long-term kit
RL416 long-term radon test kit, lab fee included
- Lab fee included
Method: Alpha track
In home: 90 days to 12 months
Locations and reports
Radon Levels in Black Hawk County, Iowa
EPA puts Black Hawk County in Zone 1, its highest radon zone, and high results are common there: 48.4% of the 3,223 radon tests reported to CDC (2008 to 2017, laboratory totals) came back at or above 4 pCi/L. Homes with elevated levels occur in all three zones, so only a test measures yours.
Data checked By Radon411Methodology
Share at 4+ pCi/L
48.4%
10.1 pts below IA
- Black Hawk
- 48.4%
- Iowa
- 58.5%
3,223 tests, 2008 to 2017
Median result
3.8pCi/L
Below action level
- Black Hawk
- 3.8 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2008 to 2017
Tests reported
3,223
7th of 99 by tests
- Black Hawk
- 3,223
- Polk
- 10,945
Reported to CDC before any fix, 2008 to 2017
EPA radon zone
Zone 1
Highest potential
- Zone 1
- 2
- 3
1 highest, 3 lowest
EPA predicts over 4 pCi/L indoors
Rank in Iowa
81 of 99
Lowest quarter
- Black Hawk
- 48.4%
- Sioux
- 84.2%
By share, of 99 with 30+ tests
Read a result for Black Hawk County
Starts at Black Hawk County's median, 3.8 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 3.8 pCi/L
Between 2 and 4 pCi/L
- Under 20 to 1.9 pCi/L
- 2 to 4consider a fix
- 4 and aboveEPA says fix it
This result is between 2 and 4 pCi/L. EPA recommends considering a fix when the level is between 2 and 4 pCi/L. Black Hawk County's median reported result, 2008 to 2017.
The data
Black Hawk County, At a glance
Black Hawk County at a glance
Predicted: EPA radon zone
EPA Zone 1: highest predicted potential
EPA puts all of Black Hawk County in
USGS geologic potential: High across 100% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Black Hawk County, 2008 to 2017, laboratory
Under 2 pCi/L: 34%2 to 4 pCi/L: 18%4 pCi/L and above: 48%
Of 3,223 pre-mitigation tests reported to CDC, not homes in this area.
| Result band | Tests Measured | Share Measured |
|---|---|---|
| Under 2 pCi/L | 1,085 | 33.7% |
| 2 to 4 pCi/L | 577 | 17.9% |
| 4 pCi/L and above | 1,561 | 48.4% |
What these figures count
These are the 3,223 tests reported to CDC for Black Hawk County over 2008 to 2017 (laboratory totals), many from homes being sold or already suspected of a problem: they describe the county's reported tests, not this house.
Measured: CDC tracking data. Figure above: 2008 to 2017, laboratory. Measured data period: 2005 to 2017 (every CDC figure on file).
Black Hawk County, Compared
Black Hawk County radon figures, compared
Calculated by Radon411In Black Hawk County, about 5 in 10 reported tests over the 2008 to 2017 laboratory totals (1,561 of 3,223) were at or above EPA's action level. Against the national pool of 35.7%, the gap is 12.7 points higher. Across 99 Iowa counties pooled together, 58.5% of tests reached that level, so Black Hawk County runs 10.1 points below its state.
Of 7 neighbours with a figure, all 7 reported a larger share at or above 4 pCi/L; the spread is 51.2% (Buchanan County) to 67.9% (Tama County). By share, Black Hawk County is 81st of 99 Iowa counties with 30 or more tests for the same period.
Half the tests came in under 3.8 pCi/L and half over it; the single highest reached 128.4 pCi/L. Below the action level, 1,085 tests (33.7%) came in under 2 pCi/L, against 21.8% statewide, and 577 tests (17.9%) fell between 2 and 4, against 19.7% statewide.
Zone 1 on EPA's map (predicted average above 4 pCi/L) and a 48.4% share point the same way here. USGS geology rates 100% of the county's land high radon potential. CDC also counts 965 tests taken after mitigation in Black Hawk County for the same period: tests in homes where a fix was already in.
CDC's ten-year totals for Black Hawk County went from 2,843 tests (2005 to 2014) to 3,223 (2008 to 2017), the share going from 50.2% to 48.4%.
Pooled shares: Radon411's sum of CDC's county counts for one period.
Black Hawk County, Geology
The ground under Black Hawk County
PredictedUSGS's geologic map puts all of Black Hawk County's mapped land in one class: high radon potential. 98.8% of it lies in the area the map calls Iowan Surface, to which USGS gives a radon index of 12, in the high band (12 to 17).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Iowan Surface | Pre-Illinoian glaical deposits and loess. | High | 12 | 98.8% |
| Loess-Covered Drift Plains | Pre-Illinoian and Illinoian glacial deposits, and loess. | High | 13 | 1.2% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Black Hawk County beside the ground around it
On high-potential ground Black Hawk County is close to Iowa as a whole: 100% of its land against 98.8%. Of the 7 counties that border it, none has as large a share of high-potential ground; Benton County comes nearest at 100%.
The map rates the ground, not the air in any home.
Local help
Black Hawk County, Local resources
Radon testing and mitigation in Black Hawk County
Listed radon businesses with an address in Black Hawk County:
- Iowa HHS Radon ProgramIowa HHS Radon Program, run by Iowa Department of Health and Human Services, licenses or certifies radon professionals, offers free or discounted test kits and states the rule for disclosing radon when a home is sold, and answers questions about testing and mitigation in Iowa.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
You can reach the Hotline by calling 1-800-383-5992 to order low-cost radon test kits and find answers to your radon questions.
- Compare kits
- Professionals in Iowa185 professionals are listed in Iowa.
Listed radon professionals by town: Waterloo, Raymond
What Iowa's program says
- Phone
- (515) 281-4928
- Licensing of radon professionals
Iowa’s radon program approves applications for persons who wish to become certified to perform radon testing or credentialed to perform mitigation and laboratories that provide radon testing devices and analytical services.
- Disclosure when a home is sold or rented
However, per Iowa Code chapters 543B.9 and 543B.18 and Iowa Administrative Code 193E Chapter 14 administered by the Iowa Real Estate Commission, a seller must disclose any known tests for the presence of radon and if yes, provide the date of last report and the result(s).
What it means
Black Hawk County, Questions
Questions about radon in Black Hawk County
Are radon levels high in Black Hawk County?
Over the 2008 to 2017 laboratory totals, 48.4% of the radon tests reported to CDC for Black Hawk County, Iowa were at or above 4 pCi/L, and the median reported pre-mitigation result was 3.8 pCi/L. Of 99 Iowa counties with 30 or more tests for the same period, 80 reported a higher share; pooled, the state comes to 58.5%.
Which counties border Black Hawk County?
Black Hawk County borders 7 counties: Bremer County, Buchanan County, Grundy County, Benton County, Butler County, Fayette County and Tama County.
Products
Black Hawk County, Products
Testing a home in Black Hawk County
In Black Hawk County, 48.4% of 3,223 tests reported to CDC over the 2008 to 2017 laboratory totals reached 4 pCi/L, against 58.5% pooled across Iowa. In Zone 1 the year-round level in Black Hawk County is the one to know: a long-term test (more than 90 days) or a monitor, with a short-term kit for a first answer.
Test kits and monitors3
See every kit and monitor
MonitorAEGTEST
HOUND-1011 rechargeable radon detector with a screen
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
Method: Semiconductor sensor
First reading: Within 6 hours
Short-term kit
Air Chek Short-Term radon test kit you hang, lab fee included
- Lab fee included
In home: 72 to 168 hours
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Black Hawk County is in EPA Zone 1, the highest predicted radon potential. Best radon monitors for Zone 1 counties like Black Hawk County
Explore
Black Hawk County, Bordering counties
Counties bordering Black Hawk County
Calculated by Radon411- Radon levels in Tama CountyEPA zone 1
67.9%at or above 4 pCi/L
Median 7.0 pCi/L · 333 tests · 19.5 points above Black Hawk County
- Radon levels in Grundy CountyEPA zone 1
66.9%at or above 4 pCi/L
Median 6.9 pCi/L · 501 tests · 18.5 points above Black Hawk County
- Radon levels in Fayette CountyEPA zone 1
62.7%at or above 4 pCi/L
Median 5.6 pCi/L · 746 tests · 14.3 points above Black Hawk County
- Radon levels in Benton CountyEPA zone 1
62.1%at or above 4 pCi/L
Median 5.6 pCi/L · 696 tests · 13.7 points above Black Hawk County
- Radon levels in Butler CountyEPA zone 1
59.9%at or above 4 pCi/L
Median 5.2 pCi/L · 377 tests · 11.5 points above Black Hawk County
- Radon levels in Bremer CountyEPA zone 1
53.0%at or above 4 pCi/L
Median 4.3 pCi/L · 957 tests · 4.6 points above Black Hawk County
- Radon levels in Buchanan CountyEPA zone 1
51.2%at or above 4 pCi/L
Median 4.1 pCi/L · 564 tests · 2.8 points above Black Hawk County
Black Hawk County, Cities and towns
Cities and towns in Black Hawk County
Black Hawk County's population has barely moved since 2020: 131,532 residents on July 1, 2025 against 131,037 then, by the Census Bureau's estimates. That works out to 232 people per square mile of land. Waterloo alone is home to 66,919 of them, 50.9% of the total. CDC's 3,223 reported tests for 2008 to 2017 work out to 24.5 per 1,000 residents (2025 estimate), close to Iowa's 29.4.
From Waterloo to Raymond, CDC publishes no figure by town: each reads Black Hawk County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Waterloo | 66,919 | −0.5% | 50.9% |
| Cedar Falls | 41,240 | +1.3% | 31.4% |
| Evansdale | 4,463 | −2.1% | 3.4% |
| Hudson | 3,028 | +19.0% | 2.3% |
| Jesupextends beyond Black Hawk County | 2,557 | +1.6% | Counted whole |
| La Porte City | 2,238 | −1.8% | 1.7% |
| Elk Run Heights | 1,053 | −1.3% | 0.8% |
| Janesvilleextends beyond Black Hawk County | 1,052 | +1.3% | Counted whole |
| Dunkerton | 835 | −0.6% | 0.6% |
| Gilbertville | 786 | +0.1% | 0.6% |
| Raymond | 748 | −1.4% | 0.6% |
Places in Black Hawk County with a city page: 1 of 1
11 incorporated places, as listed in the U.S. Census Bureau’s 2020 place reference files. Residents: U.S. Census Bureau population estimates for July 1, 2025 (Vintage 2025). A place that extends beyond Black Hawk County is counted whole, so it has no share.
Black Hawk County, Homes
Homes in Black Hawk County
Of Black Hawk County's 58,748 homes, 70% are detached houses, against 72% across Iowa; 17% are in buildings of five or more homes. Half of its homes were built before 1966, close to Iowa's 1971: 42% date from before 1960 and 16% from 2000 or later. 65% of occupied homes are lived in by their owner (Iowa: 72%); in the rest a tenant can run a test, but a fix is the landlord's to make.
| Homes | Black Hawk County | Iowa |
|---|---|---|
| Housing units | 58,748 | 1,427,175 |
| Detached houses | 70% | 72% |
| In buildings of 5 or more | 17% | 14% |
| Mobile homes | 3% | 3% |
| Built before 1960 | 42% | 39% |
| Built since 2000 | 16% | 21% |
| Middle year built | 1966 | 1971 |
| Owner-occupied | 65% | 72% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.