Skip to content
RADON411

Locations and reports

Radon in Des Moines, Iowa

Des Moines lies in 2 counties, in EPA Zone 1; 92.9% of it is in Polk County, where 64.4% of 10,945 reported tests (2008 to 2017, laboratory totals) were at or above 4 pCi/L. Homes with elevated levels occur in all three zones, so the only way to know your home's level is to test it.

Data checked By Radon411Methodology

How to test this homeFind a certified tester

  • Share at 4+ pCi/L

    64.4%

    5.9 pts above IA

    Polk
    64.4%
    Iowa
    58.5%

    Polk, 51st of 99 in IA, 2008 to 2017

  • Median result

    5.6pCi/L

    Action level reached

    Polk
    5.6 pCi/L
    EPA
    4.0 pCi/L

    Midpoint of Polk's tests, 2008 to 2017

  • Highest county

    66.0%

    Warren

    Warren
    66.0%
    Polk
    64.4%

    2 counties, 2 with 30+ tests, 2008 to 2017

  • EPA radon zone

    Zone 1

    Highest potential

    1. Zone 1
    2. 2
    3. 3

    1 highest, 3 lowest

    Polk; Warren Zone 1

  • Tests reported

    10,945

    In Polk

    Polk
    10,945
    Warren
    1,513

    Reported to CDC before any fix, 2008 to 2017

Read a result for Des Moines

Starts at Polk County's median, 5.6 pCi/L

5.6pCi/L

EPA’s own thresholds; the figures are the area’s, never this home’s.

EPA’s reading of 5.6 pCi/L

At or above 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 at or above 4 pCi/L. EPA recommends fixing a home when the radon level is 4 pCi/L or higher. Polk County's median reported result, 2008 to 2017.

Interpret this readingWhat a fix costs

The data

Des Moines, What is published

What is published for Des Moines

Information:

Every figure for Des Moines is a county's

Radon data is published by county, not by city, and Des Moines reaches into 2 counties: Polk County and Warren County. Each has its own EPA zone and its own CDC test figures, set side by side below and each labelled with its county. Only a test tells you about one home.

Des Moines covers 88.2 square miles of land: 92.9% of it lies in Polk County and 7.1% in Warren County. About 212,086 people live there, 2,405 to the square mile.

Des Moines, Counties

Des Moines's counties, side by side

Measured

Each county's own EPA zone and its own published CDC figures for 2008 to 2017, laboratory, the newest period any of them has. A county without a figure for that period is shown without one, never with a figure from another year.

  • Polk County
    EPA zone
    Zone 1: Highest predicted potential
    At or above 4 pCi/L
    64.4%
    Median result
    5.6 pCi/L
    Tests reported
    10,945 tests
    Annual years on file
    None
  • Warren County
    EPA zone
    Zone 1: Highest predicted potential
    At or above 4 pCi/L
    66.0%
    Median result
    6.3 pCi/L
    Tests reported
    1,513 tests
    Annual years on file
    None
The counties Des Moines lies in, each with its own EPA zone and its own published CDC figures for 2008 to 2017, laboratory
CountyEPA zoneReported tests at or above 4 pCi/LMedian reported resultTests reportedAnnual years on file
Polk CountyZone 1: Highest predicted potential64.4%5.6 pCi/L10,945 testsNone
Warren CountyZone 1: Highest predicted potential66.0%6.3 pCi/L1,513 testsNone

Des Moines spans 2 counties, each with its own EPA zone and its own CDC figure: Polk County (Zone 1, 64.4% of 10,945 tests) and Warren County (Zone 1, 66.0% of 1,513 tests).

Polk County ranks 51st of 99 Iowa counties with 30 or more tests for that period, 5.9 points above the 58.5% pooled across Iowa's counties, 28.7 points above the national pool of 35.7%. Of the city's other county, Warren County reported 66.0%.

The counties nearest Des Moines with a CDC figure for 2008 to 2017, laboratory, measured from the middle of the city: Dallas County (24 miles, 58.5% of 2,352 tests), Madison County (27 miles, 62.3% of 318 tests) and Jasper County (30 miles, 73.3% of 746 tests). Across the 8 nearest, the share at or above 4 pCi/L runs from 39.3% to 73.3%; the farthest of them, Lucas County, is 40 miles away at 39.3%.

The directory lists 8 businesses with an address in Des Moines, 8 for testing and 6 for mitigation. Iowa's other cities with a page of their own: Ames, Sioux City, Iowa City and Waterloo.

Against Iowa and its other counties

Radon test figures for the counties Des Moines lies in
CountyShare of Des MoinesTestsAt or above 4 pCi/LMedianIowa, pooledRank in the stateEPA zone
Polk County92.9%10,94564.4%5.6 pCi/L58.5%51 of 99Zone 1
Warren County7.1%1,51366.0%6.3 pCi/L58.5%48 of 99Zone 1

Shares of tests people chose to run and report, by county (2008 to 2017, laboratory); the state's is its counties' counts added up, calculated by Radon411. Only a test measures a home.

The counties around Des Moines

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

Nearest counties to Des Moines with 30 or more tests
CountyDistanceTestsAt or above 4 pCi/LMedian
Dallas County24 mi2,35258.5%4.9 pCi/L
Madison County27 mi31862.3%6.0 pCi/L
Jasper County30 mi74673.3%8.2 pCi/L
Marion County31 mi1,15167.3%6.0 pCi/L
Story County33 mi2,56859.9%5.0 pCi/L
Boone County36 mi1,13468.7%6.0 pCi/L
Clarke County39 mi12045.8%3.5 pCi/L
Lucas County40 mi8439.3%3.3 pCi/L

The median reported pre-mitigation result for 2008 to 2017, laboratory was 5.6 pCi/L in Polk County and 6.3 pCi/L in Warren County.

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

Des Moines, Geology

The ground under Des Moines

Predicted

USGS's geologic map puts all of Des Moines' mapped land in one class: high radon potential. The map puts 68.6% of Des Moines in the area it calls Loess-Covered Drift Plains and 31.4% in Des Moines Lobe. USGS gives the first a radon index of 13 and the second 12, both in the high band (12 to 17).

USGS's geologic areas under Des Moines
AreaThe rock, in USGS's wordsPotentialRadon indexShare of land
Loess-Covered Drift PlainsPre-Illinoian and Illinoian glacial deposits, and loess.High1368.6%
Des Moines LobeCalcareous loamy till derived from shale, limestone, dolomite, sandstone.High1231.4%

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

Des Moines beside its counties and Iowa

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

Share of land by USGS radon potential: Des Moines, the counties it lies in and Iowa
AreaEPA zoneLow potentialModerate potentialHigh potential
Des MoinesBy countyNoneNone100%
Polk CountyZone 1NoneNone100%
Warren CountyZone 1NoneNone100%
Iowa99 counties, pooled by land areaVariesNone1.2%98.8%

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

Des Moines, Homes

Homes in Des Moines

Of Des Moines' 97,457 homes, 62% are detached houses, against 62% across Polk County; 27% are in buildings of five or more homes. The homes are older than Polk County's as a whole: half were built before 1960 (1981 for Polk County), and 50% date from before 1960. 60% of occupied homes are lived in by their owner (Polk County: 67%); in the rest a tenant can run a test, but a fix is the landlord's to make.

Homes in Des Moines, Polk County, Iowa, 2019 to 2023
HomesDes MoinesPolk CountyIowa
Housing units97,457215,0161,427,175
Detached houses62%62%72%
In buildings of 5 or more27%24%14%
Mobile homes3%2%3%
Built before 196050%29%39%
Built since 200015%29%21%
Middle year built196019811971
Owner-occupied60%67%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

Des Moines, Professionals

Radon professionals listed in Des Moines

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

8 listings with Des Moines as the city. See radon mitigation and testing in Des Moines, or all radon professionals in Iowa.

Des Moines, Local resources

Local resources for Des Moines

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

Des Moines, Questions

Questions about radon in Des Moines

What radon zone is Des Moines in?

Both counties Des Moines reaches into (Polk County and Warren County) are in Zone 1, the map's highest class: a predicted county average above 4 pCi/L. EPA zones counties, not cities, so that is the zone for every part of Des Moines.

What are radon levels in Des Moines?

64.4% of the 10,945 tests reported from Polk 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 Des Moines. The median reported result was 5.6 pCi/L. Warren County reported 66.0% of 1,513 tests; the counties are kept apart.

Should I test my home in Des Moines?

Yes. About 7,049 of the 10,945 tests reported from Polk County were at or above 4 pCi/L. That is above Iowa's pooled 58.5%, and ranks Polk County 51st 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 Des Moines built on, as far as radon goes?

68.6% of Des Moines sits on what USGS's map calls "Loess-Covered Drift Plains", rated high for radon potential, radon index 13; another 31.4% is "Des Moines Lobe", in the same class.

Is radon higher in the counties around Des Moines?

Some are and some are not. Against Polk County's 64.4%, 3 of the 8 nearest counties with a figure report more and 5 less, from Lucas County (39.3%, 40 miles off) to Jasper County (73.3%, 30 miles off).

Who tests for or fixes radon in Des Moines?

Radon411's directory has 8 businesses with an address in Des Moines, 8 listed for testing and 6 for mitigation. Every entry names the public list it was taken from. Radon professionals in Des Moines.

The answers use the published figures of Polk County and Warren County, the counties Des Moines lies in.

Explore