Manganese is widespread in Anoka County wells.
1 widespread, 1 worth checking, 3 rare out of 5 health checks.
From 201 wells tested in Anoka County since 2000; your own well needs its own test. How to read this
Not charted, because fewer than 10 wells were tested: uranium (9), radon (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 4 people 85,349 people
Nobody else tests these wells. Only you do.
People on wells: EPA researchers' 2020 estimate
How deep wells go here
Middle depth: some shelter from the surface, not complete.
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 Anoka County compares with Minnesota and the counties around it.
Each result puts Anoka County next to the 6 counties that border it, on the chart's 0 to 50% scale.
This one is widespread in Anoka County wells.
Manganese20 of 47 wells over
Too few tested to show: Chisago.
This one is worth checking in Anoka County.
Arsenic17 of 128 wells over
These 3 are rare in Anoka County.
Nitrate6 of 196 wells over
Too few tested to show: Ramsey.
Lead0 of 128 wells over
Fluoride0 of 125 wells over
Too few tested to show: Ramsey.
Too few Anoka County wells were tested for these 2.
Uranium9 wells tested
Radon in water1 well tested
Coliform bacteria turned up in 52 of 58 tested Anoka County wells, so test for it every year.
Coliform bacteria52 of 58 wells had it
Too few tested to show: Chisago, Hennepin, Isanti, Ramsey, Sherburne.
E. coli44 of 51 wells had it
Too few tested to show: Chisago, Hennepin, Isanti, Ramsey, Sherburne.
E. coli means human or animal waste is getting in, so if a test of your Anoka County well finds it, boil drinking water until the well is fixed.
Iron reached staining levels in 63 of 130 tested wells, and it isn't a health risk.
Iron stains63 of 130 wells had it
Anoka County has 201 tested wells, and the busiest decade for testing was the 2010s.
Only 33 of the 201 wells have a test from 2020 or later, so a fresh test of your own well tells you more than any of these.
Most Anoka 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 4 things to check in Anoka County.
- Bacteria
- Nitrate
- Manganese
- Arsenic
What Minnesota offers well owners
- Free testingWe didn't find a free program for all of Minnesota. Minnesota's private well page
- Certified labsMinnesota's list of certified labs
- Well recordsMinnesota's well record search
- New wellsThe well contractor must collect an initial water sample after construction to test for coliform bacteria, nitrate, and arsenic before the well is used.
Half the household wells here are shallower than 136 feet.
That comes from 26,454 household wells in Minnesota's drilling records. Most wells of every kind here are 90 to 181 feet deep. Wells as deep as Anoka County's are usually better protected from fertilizer and bacteria at the surface, but they can pick up more of what's in the rock, like arsenic and uranium. Typical household wells here go deeper than in 44 of the 86 other Minnesota counties with enough drilling records.
Look up your own well's depth in Minnesota'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 Anoka County.
Anoka 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 12 town water systems in Anoka County test for PFAS. 10 found some PFAS, all below the new limits. Only 33 wells in Anoka County have 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 Anoka County
Is well water in Anoka County safe to drink?
20 of 47 wells tested in Anoka County had manganese over the limit, about 4 in 10. Across Minnesota it's about 2 in 10. That's a bigger share than in 41 of the 44 other Minnesota counties with 10 or more tested wells, leaving out 1 county whose results are likely overstated. So test your own well for manganese before you count on it.
Where can I get my well tested in Anoka County?
Use a lab Minnesota has certified for drinking water. Minnesota's list is linked above, in the box about testing. Ask for bacteria, nitrate, manganese and arsenic, the tests that matter most in Anoka County.
How deep are wells in Anoka County?
Half the household wells here are shallower than 136 feet. Typical household wells here go deeper than in 44 of the 86 other Minnesota counties with enough drilling records.
How does Anoka County compare with the counties around it?
For manganese, the share of tested wells over the limit: 1 of the 5 neighboring counties with data had a higher share than Anoka County, at 43%. Hennepin had the most, at 61%. Groundwater doesn't stop at county lines, so Hennepin's 61% is worth knowing about if you live near it.
How often should I test my well in Anoka County?
In Anoka County, 52 of 58 tested wells had coliform bacteria, so the CDC's advice matters here: 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 Anoka County numbers come from
- People on wells: 85,349 in Anoka County, from EPA estimates built on the 2020 Census (Murray et al.).
- Lab tests: 2,963 well water samples from 201 wells in the Water Quality Portal, run by the USGS and EPA, 2000 to 2025.
- Well depths: 26,454 Minnesota drilling records for Anoka County, gathered in the US Groundwater Well Database (Lin and others, 2024).
- Neighboring counties: the 6 counties that share a border with Anoka County, from the Census Bureau's county adjacency file.
- PFAS: EPA tests of 12 town water systems in Anoka County under the Fifth Unregulated Contaminant Monitoring Rule, 2023 to 2025.
- Radon: Anoka County is zone 2 on the EPA Map of Radon Zones.
- State programs and links: Minnesota Department of Health, checked November 1, 2026.