Short-term kit
RA100 short-term liquid scintillation radon test kit
- Lab fee extra
Method: Liquid scintillation
In home: 48 to 96 hours
Locations and reports
Radon Levels in Kewaunee County, Wisconsin
EPA puts Kewaunee County in Zone 2, its middle radon zone, and high results are common there: 44.6% of the 56 radon tests reported to CDC (2023) 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
44.6%
8.9 pts above WI
- Kewaunee
- 44.6%
- Wisconsin
- 35.7%
56 tests, 2023
Median result
3.7pCi/L
Below action level
- Kewaunee
- 3.7 pCi/L
- EPA
- 4.0 pCi/L
Midpoint of the tests, 2023
Tests reported
56
56th of 69 by tests
- Kewaunee
- 56
- Dane
- 2,887
Reported to CDC before any fix, 2023
EPA radon zone
Zone 2
Moderate potential
- 1
- Zone 2
- 3
1 highest, 3 lowest
EPA predicts 2 to 4 pCi/L indoors
Rank in Wisconsin
18 of 69
Middle half
- Kewaunee
- 44.6%
- Langlade
- 65.8%
By share, of 69 with 30+ tests
Read a result for Kewaunee County
Starts at Kewaunee County's median, 3.7 pCi/L
EPA’s own thresholds; the figures are the area’s, never this home’s.
EPA’s reading of 3.7 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. Kewaunee County's median reported result, 2023.
The data
Kewaunee County, At a glance
Kewaunee County at a glance
Predicted: EPA radon zone
EPA Zone 2: moderate predicted potential
Kewaunee County is a
USGS geologic potential: Moderate across 61% of the county's area
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
Radon tests reported for Kewaunee County, 2023
| Year | Share of reported tests at or above 4 pCi/L |
|---|---|
| 2014 | 28.6% |
| 2015 | 50.0% |
| 2016 | 41.5% |
| 2017 | 42.0% |
| 2019 | 38.9% |
| 2020 | 28.6% |
| 2021 | 40.0% |
| 2022 | 55.6% |
| 2023 | 44.6% |
2023: 44.6%. Across these years the share ran from 28.6% to 55.6%. Each column counts radon tests reported to CDC that year, not homes.
What these figures count
These are the 56 tests reported to CDC for Kewaunee County over 2023, 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: 2023. Measured data period: 2005 to 2023 (every CDC figure on file).
Kewaunee County, Compared
Kewaunee County radon figures, compared
Calculated by Radon411In Kewaunee County, about 4 in 10 reported tests in 2023 (25 of 56) were at or above EPA's action level. Against the national pool of 33.4%, the gap is 11.2 points higher. Across 72 Wisconsin counties pooled together, 35.7% of tests reached that level, so Kewaunee County runs 8.9 points above its state.
Of 3 neighbours with a figure, none reported a larger share at or above 4 pCi/L; the spread is 23.0% (Brown County) to 42.3% (Door County). By share, Kewaunee County is 18th of 69 Wisconsin counties with 30 or more tests for the same period.
Year by year, 2014 opened at 28.6% and 2023 closed at 44.6% (up 16.0 points), with 2022 the high at 55.6%. Half the tests came in under 3.7 pCi/L and half over it; the single highest reached 32.9 pCi/L. Below the action level, 11 tests (19.6%) came in under 2 pCi/L, against 41.4% statewide, and 20 tests (35.7%) fell between 2 and 4, against 23.0% statewide.
Zone 2 on EPA's map (predicted average between 2 and 4 pCi/L) and a 44.6% share point the same way here. USGS geology rates 61% of the county's land moderate radon potential.
The busiest year on file was 2016, with 82 tests reported; the quietest, 2020, had 21.
Kewaunee CountyWisconsin, pooled
44.6% % of tests35.7% % of tests
| Year | Tests | Kewaunee County, at or above 4 pCi/L | Wisconsin, pooled |
|---|---|---|---|
| 2014 | 49 | 28.6% | 51.1% |
| 2015 | 38 | 50.0% | 51.6% |
| 2016 | 82 | 41.5% | 45.2% |
| 2017 | 50 | 42.0% | 44.8% |
| 2019 | 54 | 38.9% | 42.9% |
| 2021 | 35 | 40.0% | 39.9% |
| 2022 | 63 | 55.6% | 42.9% |
| 2023 | 56 | 44.6% | 35.7% |
Pooled shares: Radon411's sum of CDC's county counts for one period.
Kewaunee County, Geology
The ground under Kewaunee County
PredictedUSGS's geologic map splits Kewaunee County: 60.7% of its land is moderate radon potential and 12.1% high and 26.5% low. The map puts 60.7% of Kewaunee County in the area it calls Green Bay Lobe and 26.5% in Eastern Ridges and Lowlands, with one smaller area beside them. USGS gives the first a radon index of 10, in the moderate band (9 to 11), and the second 8, in the low band (5 to 8).
| Area | The rock, in USGS's words | Potential | Radon index | Share of land |
|---|---|---|---|---|
| Green Bay Lobe | Glacial deposits derived from carbonate and igneous rocks. | Moderate | 10 | 60.7% |
| Eastern Ridges and Lowlands | Glacial lake deposits, clayey glacial deposits. | Low | 8 | 26.5% |
| Eastern Ridges and Lowlands | Glacial deposits derived from Ordovician carbonate rocks. | High | 12 | 12.1% |
Names, descriptions and indexes: U.S. Geological Survey, Geologic Radon Potential Map (2025). Shares: Radon411, from the map cut to the boundary.
Kewaunee County beside the ground around it
Wisconsin as a whole has more high-potential ground than Kewaunee County: 34.8% of its land, against 12.1% here. Of the 3 counties that border it, 2 have more high-potential ground, Door County the most at 89.6%.
The map rates the ground, not the air in any home.
Local help
Kewaunee County, Local resources
Radon testing and mitigation in Kewaunee County
- Wisconsin's radon programWisconsin Department of Health ServicesWisconsin's radon program does not license radon professionals and offers free or discounted test kits, and answers questions about testing and mitigation in Wisconsin.Visit the program’s page(opens in a new tab)
- Free and low-cost kitsThe program says:
We recommend starting with your regional Radon Information Center since many centers provide test kits for free or reduced cost, and often with laboratory fees covered.
- Compare kits
- Professionals in Wisconsin19 professionals are listed in Wisconsin.
What Wisconsin's program says
- Phone
- 1-888-569-7236
- DHSRadon@dhs.wisconsin.gov
- Licensing of radon professionals
The State of Wisconsin does not require contractors performing radon measurement or mitigation work to be state licensed or nationally certified.
What it means
Kewaunee County, Questions
Questions about radon in Kewaunee County
Are radon levels high in Kewaunee County?
In 2023, 44.6% of the radon tests reported to CDC for Kewaunee County, Wisconsin were at or above 4 pCi/L, and the median reported pre-mitigation result was 3.7 pCi/L. Of 69 Wisconsin counties with 30 or more tests for the same period, 17 reported a higher share; pooled, the state comes to 35.7%.
Which counties border Kewaunee County?
Kewaunee County borders 3 counties: Brown County, Manitowoc County and Door County.
Products
Kewaunee County, Products
Testing a home in Kewaunee County
In Kewaunee County, 44.6% of 56 tests reported to CDC in 2023 reached 4 pCi/L, against 35.7% pooled across Wisconsin. In Zone 2 a short-term kit (2 to 90 days) is the quick first check in Kewaunee County; a long-term test tells the year-round average.
Test kits and monitors3
See every kit and monitor
Long-term kit
RL116 long-term radon test kit
- Lab fee extra
Method: Alpha track
In home: 90 days to 12 months
MonitorAEGTEST
HOUND-3699 radon monitor with a 2.1-inch touchscreen
- C-NRPP 2024/25: Not included
- Battery
- Alarm
- Screen
First reading: Within 1 hour
- See every kit and monitor Test kits and monitors
Test kits and monitors: 1 of 3
Explore
Kewaunee County, Bordering counties
Counties bordering Kewaunee County
Calculated by Radon411- Radon levels in Door CountyEPA zone 1
42.3%at or above 4 pCi/L
Median 3.0 pCi/L · 156 tests · 2.3 points below Kewaunee County
- Radon levels in Manitowoc CountyEPA zone 2
31.1%at or above 4 pCi/L
Median 2.2 pCi/L · 209 tests · 13.5 points below Kewaunee County
- Radon levels in Brown CountyEPA zone 2
23.0%at or above 4 pCi/L
Median 1.4 pCi/L · 551 tests · 21.6 points below Kewaunee County
Kewaunee County, Cities and towns
Cities and towns in Kewaunee County
The Census Bureau estimates 20,758 residents in Kewaunee County for July 1, 2025, 206 more than in 2020 (+1.0%). That works out to 61 people per square mile of land. No town dominates: Algoma, the largest, has 3,225 residents, 15.5% of the total. Together its 4 incorporated places hold 45.7% of those residents; the other 54.3% live outside any of them. CDC's 56 reported tests for 2023 work out to 2.7 per 1,000 residents (2025 estimate), close to Wisconsin's 3.5.
From Algoma to Casco, CDC publishes no figure by town: each reads Kewaunee County's.
| Place | Residents | Since 2020 | Share of residents |
|---|---|---|---|
| Algoma | 3,225 | −0.5% | 15.5% |
| Kewaunee | 2,793 | −1.0% | 13.5% |
| Luxemburg | 2,784 | +3.6% | 13.4% |
| Casco | 692 | +10.4% | 3.3% |
4 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).
Kewaunee County, Homes
Homes in Kewaunee County
Kewaunee County is a place of houses on their own lots: 81% of its 9,325 homes are detached single-family houses, against 66% across Wisconsin. Half of its homes were built before 1970, close to Wisconsin's 1975: 41% date from before 1960 and 17% from 2000 or later. Owners live in 85% of the occupied homes (Wisconsin: 68%), so for most households a test and a fix are their own to order.
| Homes | Kewaunee County | Wisconsin |
|---|---|---|
| Housing units | 9,325 | 2,750,750 |
| Detached houses | 81% | 66% |
| In buildings of 5 or more | 6% | 17% |
| Mobile homes | 4% | 3% |
| Built before 1960 | 41% | 34% |
| Built since 2000 | 17% | 20% |
| Middle year built | 1970 | 1975 |
| Owner-occupied | 85% | 68% |
Census Bureau, American Community Survey, 2019 to 2023: estimates from a sample of homes, looser for a small place. Shares by Radon411.