Only 1 health check had enough tested wells in Sumner County, and it came back rare.
The only health check here came back rare.
From 12 wells tested in Sumner County since 2003; your own well needs its own test. How to read this
Not charted, because fewer than 10 wells were tested: nitrate (1), arsenic (1), uranium (1), radon (1), manganese (1), lead (1).
Rare: under 5%Worth checking: 5 to 15%Widespread: 15%+
Lab results: Water Quality Portal (USGS and EPA)
Who drinks from a well here
1 in 3 people 7,198 people
Nobody else tests these wells. Only you do.
People on wells: EPA researchers' 2020 estimate
How deep wells go here
Shallow wells: watch for fertilizer and germs from above.
Well depths: US Groundwater Well Database
Radon risk (a gas from rock)
Possible here. A home air test is inexpensive.
Radon zones: EPA map
Here's how Sumner County compares with Kansas and the counties around it.
Each result puts Sumner County next to the 7 counties that border it, on the chart's 0 to 50% scale.
The only health check in Sumner County is rare.
Too few Sumner County wells were tested for these 6.
Nitrate1 well tested
Arsenic1 well tested
Uranium1 well tested
Radon in water1 well tested
Manganese1 well tested
Lead1 well tested
None of the 1 Sumner County wells tested for bacteria had it, but every well needs a yearly test.
Coliform bacteria0 of 1 wells had it
E. coli0 of 1 wells had it
E. coli means human or animal waste is getting in, so if a test of your Sumner County well finds it, boil drinking water until the well is fixed.
Iron reached staining levels in 2 of 12 tested wells, and it isn't a health risk.
Iron stains2 of 12 wells had it
Too few tested to show: Butler, Grant, OK, Harper, Kingman.
Most of the 12 wells tested in Sumner County were last tested before 2010.
An old result shows the water as it was then, so treat these 12 wells as a starting point and test your own.
Most Sumner County wells in these records were tested for research or because someone suspected a problem, which can push the shares above what a typical home well would show (how we read the numbers).
One mail-in lab test covers the 3 things to check in Sumner County.
- Bacteria
- Nitrate
- Arsenic
What Kansas offers well owners
- Free testingWe didn't find a free program for all of Kansas. Kansas's private well page
- Certified labsWe didn't find an online list.
- Well recordsKansas's well record search
Half the household wells here are shallower than 50 feet.
That comes from 1,114 household wells in Kansas's drilling records. Most wells of every kind here are 38 to 65 feet deep. Wells as shallow as Sumner County's pick up bacteria and nitrate from the surface more easily, so the yearly test matters even more here. Typical household wells here are shallower than in 93 of the 104 other Kansas counties with enough drilling records.
Look up your own well's depth in Kansas's well record search, or see how to find it.
Well depths: US Groundwater Well Database
Here's what we know about radon and PFAS in Sumner County.
Sumner County is in the EPA's middle radon zone. An indoor air test is cheap and tells you whether to look at your water. Radon guide
Between 2023 and 2025 the EPA had 2 town water systems in Sumner County test for PFAS. 2 found some PFAS, all below the new limits. No well in Sumner County has public PFAS results, so the town systems are the best clue to what's in the groundwater nearby. PFAS guide
Radon zones: EPA Map of Radon Zones. PFAS: EPA tests of town water systems, 2023 to 2025
Questions people ask about well water in Sumner County
Is well water in Sumner County safe to drink?
Most tested wells in Sumner County came in under the limits. Of 1 health check with enough tests, fluoride came closest, at 0 of 12 wells over. Every well is different, so test yours for bacteria, nitrate and arsenic.
Where can I get my well tested in Sumner County?
Use a lab Kansas has certified for drinking water. Kansas's list is linked above, in the box about testing. Ask for bacteria, nitrate and arsenic, the tests that matter most in Sumner County.
How deep are wells in Sumner County?
Half the household wells here are shallower than 50 feet. Typical household wells here are shallower than in 93 of the 104 other Kansas counties with enough drilling records.
How does Sumner County compare with the counties around it?
For fluoride, the share of tested wells over the limit: Sumner County and all 3 neighboring counties with data had no tested wells over the limit. Groundwater doesn't stop at county lines, so Cowley's 0% is worth knowing about if you live near it.
How often should I test my well in Sumner County?
None of the 1 wells tested for bacteria in Sumner County had it, but the CDC still says to test for bacteria and nitrate every year, and right away after a flood, a repair, or any change in taste or smell.
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Where the Sumner County numbers come from
- People on wells: 7,198 in Sumner County, from EPA estimates built on the 2020 Census (Murray et al.).
- Lab tests: 32 well water samples from 12 wells in the Water Quality Portal, run by the USGS and EPA, 2003 to 2018.
- Well depths: 1,114 Kansas drilling records for Sumner County, gathered in the US Groundwater Well Database (Lin and others, 2024).
- Neighboring counties: the 7 counties that share a border with Sumner County, from the Census Bureau's county adjacency file.
- PFAS: EPA tests of 2 town water systems in Sumner County under the Fifth Unregulated Contaminant Monitoring Rule, 2023 to 2025.
- Radon: Sumner County is zone 2 on the EPA Map of Radon Zones.
- State programs and links: Kansas Department of Health and Environment, checked November 1, 2026.