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Radon in Waterloo, Iowa

EPA puts Black Hawk County, where Waterloo is, 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

How to test this homeFind a certified tester

  • Share at 4+ pCi/L

    48.4%

    10.1 pts below IA

    Black Hawk
    48.4%
    Iowa
    58.5%

    Black Hawk, 81st of 99 in IA, 2008 to 2017

  • Median result

    3.8pCi/L

    Below action level

    Black Hawk
    3.8 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of Black Hawk's tests, 2008 to 2017

  • Nearest county

    53.0%

    Bremer, 20 miles

    Bremer
    53.0%
    Black Hawk
    48.4%

    957 tests, 2008 to 2017

  • EPA radon zone

    Zone 1

    Highest potential

    1. Zone 1
    2. 2
    3. 3

    1 highest, 3 lowest

    Black Hawk, where Waterloo is

  • Tests reported

    3,223

    In Black Hawk

    Black Hawk
    3,223
    Bremer
    957

    Reported to CDC before any fix, 2008 to 2017

Read a result for Waterloo

Starts at Black Hawk County's median, 3.8 pCi/L

3.8pCi/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

  1. Under 20 to 1.9 pCi/L
  2. 2 to 4consider a fix
  3. 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.

Interpret this readingWhat a fix costs

The data

Waterloo, What is published

What is published for Waterloo

Information:

Every figure for Waterloo is a county's

Radon data is published by county, not by city, so for Waterloo it is Black Hawk County's: its EPA zone (Zone 1) and the 3,223 tests reported to CDC for 2008 to 2017, laboratory. Only a test tells you about one home.

Waterloo covers 61.6 square miles of land, all of it in Black Hawk County. About 66,919 people live there, 1,086 to the square mile.

Waterloo, Counties

The county Waterloo lies in

Measured

Black Hawk County's EPA zone and the figures CDC publishes for it, 2008 to 2017, laboratory.

Black Hawk CountyZone 1Highest predicted potential

48.4%
Reported tests at or above 4 pCi/L
3.8 pCi/L
Median reported result
3,223 tests
Tests reported to CDC
None
Yearly figures on file

Black Hawk County ranks 81st of 99 Iowa counties with 30 or more tests for that period, 10.1 points below the 58.5% pooled across Iowa's counties, 12.7 points above the national pool of 35.7%.

The counties nearest Waterloo with a CDC figure for 2008 to 2017, laboratory, measured from the middle of the city: Bremer County (20 miles, 53.0% of 957 tests), Grundy County (23 miles, 66.9% of 501 tests) and Buchanan County (26 miles, 51.2% of 564 tests). Across the 8 nearest, the share at or above 4 pCi/L runs from 51.2% to 67.9%; the farthest of them, Chickasaw County, is 39 miles away at 59.0%.

The directory lists 3 businesses with an address in Waterloo, 3 for testing. Iowa's other cities with a page of their own: Des Moines, Ames, Sioux City and Iowa City.

The counties around Waterloo

By distance from the middle of Waterloo; counties with 30 or more tests.

Nearest counties to Waterloo with 30 or more tests
CountyDistanceTestsAt or above 4 pCi/LMedian
Bremer County20 mi95753.0%4.3 pCi/L
Grundy County23 mi50166.9%6.9 pCi/L
Buchanan County26 mi56451.2%4.1 pCi/L
Butler County28 mi37759.9%5.2 pCi/L
Tama County30 mi33367.9%7.0 pCi/L
Benton County32 mi69662.1%5.6 pCi/L
Fayette County36 mi74662.7%5.6 pCi/L
Chickasaw County39 mi49859.0%4.9 pCi/L

Predicted: EPA Map of Radon Zones, by county. Measured: CDC tracking data, by county, 2008 to 2017, laboratory.

Waterloo, Geology

The ground under Waterloo

Predicted

USGS's geologic map puts all of Waterloo's mapped land in one class: high radon potential. All 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).

USGS's geologic areas under Waterloo
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
Iowan SurfacePre-Illinoian glaical deposits and loess.High12100%

Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.

Waterloo beside its county and Iowa

All of Waterloo, like all of Black Hawk County, is rated high. On high-potential ground Waterloo is close to Iowa as a whole: 100% of its land against 98.8%.

Share of land by USGS radon potential: Waterloo, the county it lies in and Iowa
AreaEPA zoneLow potentialModerate potentialHigh potential
WaterlooBy countyNoneNone100%
Black Hawk CountyZone 1NoneNone100%
Iowa99 counties, pooled by land areaVariesNone1.2%98.8%

The map rates the ground, not the air in any home.

Waterloo, Homes

Homes in Waterloo

Of Waterloo's 32,170 homes, 69% are detached houses, against 70% across Black Hawk County; 17% are in buildings of five or more homes. Half of its homes were built before 1961, close to Black Hawk County's 1966: 48% date from before 1960 and 11% from 2000 or later. 61% of occupied homes are lived in by their owner (Black Hawk County: 65%); in the rest a tenant can run a test, but a fix is the landlord's to make.

Homes in Waterloo, Black Hawk County, Iowa, 2019 to 2023
HomesWaterlooBlack Hawk CountyIowa
Housing units32,17058,7481,427,175
Detached houses69%70%72%
In buildings of 5 or more17%17%14%
Mobile homes3%3%3%
Built before 196048%42%39%
Built since 200011%16%21%
Middle year built196119661971
Owner-occupied61%65%72%

Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.

Local help

Waterloo, Professionals

Radon professionals listed in Waterloo

Businesses whose listed city is Waterloo, from the state registries and listings in the Radon411 directory, with the same business and certification status the directory shows.

3 listings with Waterloo as the city. See radon testing in Waterloo, or all radon professionals in Iowa.

Waterloo, Local resources

Local resources for Waterloo

Who to ask in Iowa: its radon program, test kits and professionals.

The program's own words on licensing and disclosure are on the Iowa page.

What it means

Waterloo, Questions

Questions about radon in Waterloo

What radon zone is Waterloo in?

Waterloo has no zone of its own: it shares Black Hawk County's, Zone 1, the map's highest class: a predicted county average above 4 pCi/L.

What are radon levels in Waterloo?

48.4% of the 3,223 tests reported from Black Hawk County for 2008 to 2017 (laboratory totals) were at or above 4 pCi/L, the level at which EPA says to fix a home: high results are ordinary around Waterloo. The median reported result was 3.8 pCi/L.

Should I test my home in Waterloo?

Yes. About 1,560 of the 3,223 tests reported from Black Hawk County were at or above 4 pCi/L. That is below Iowa's pooled 58.5%, and still not a reason to skip it, and ranks Black Hawk County 81st of the 99 Iowa counties with 30 or more tests. No map says which homes those are. How to test a home.

What ground is Waterloo built on, as far as radon goes?

USGS's geologic map puts all of Waterloo on one named area, "Iowan Surface", rated high for radon potential, radon index 12.

Is radon higher in the counties around Waterloo?

Yes, in every direction measured. Each of the 8 nearest counties with a figure reports a larger share of high tests than Black Hawk County's 48.4%; the highest is Tama County (67.9%, 30 miles off).

Who tests for or fixes radon in Waterloo?

Radon411's directory has 3 businesses with an address in Waterloo, all listed for testing, none for mitigation. Every entry names the public list it was taken from. Radon professionals in Waterloo.

The answers use the published figures of Black Hawk County, the county Waterloo lies in.

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