Well Water Nerd

Well water in Kennebec County, Maine

1in4

Testing strongly recommended

private wells tested in Kennebec County had arsenic above the Maine guideline (10 ug/L), according to Maine CDC.

5,244 private wells tested in state summaries; 2,484 test results across 17 contaminants from at least 450 wells, 1957 to 2026; PFOA has the most at 450. Data refreshed September 15, 2026.

Compiled by Nick at Well Water Nerd from public records. How these pages are built

Maine DEP samples private wells near fields where sludge or septage was spread and near other known PFAS sources, and resamples detections. PFAS shares describe wells that were tested for a reason, not every well in the area. In that targeted sampling, 25% of 450 PFOA results in Kennebec County were above the EPA limit of 4 ng/L. In that targeted sampling, 12% of 450 PFOS results in Kennebec County were above the EPA limit of 4 ng/L.

An estimated 65,729 people in Kennebec County get their drinking water from a private well, per USGS 2015 county water use. That is about 55% of residents.

Separately, the USGS national arsenic model estimates that 23% of the 65,729 people on private wells in Kennebec County draw water above 10 ug/L (the model's range is 19% to 28%), from geology and well depth rather than local tests.

What homeowner tests found

Maine Tracking Network private well summaries: private wells tested and reported to the state. Shares are against the level the state applies to each contaminant, named in the last column; several are stricter than EPA. County and state figures combine the town summaries, weighted by wells tested; medians are not combined.

ContaminantAbove state levelWells testedMedian95th pctHighestState level
Arsenic4,74310 ug/L
Uranium4,00530 ug/L
Manganese4,407300 ug/L
Fluoride5,0152 mg/L
Nitrate5,24210 mg/L
Nitrite5,2441 mg/L

What individual samples found

Each row summarizes every public sample for that contaminant inside Kennebec County. Above limit means above the EPA maximum contaminant level; where EPA has no enforceable limit, the row shows a health guideline or nuisance level instead.

ContaminantAbove limitSamplesDetectedMedianHighestLimit
Arsenic
1999 to 2011
11499%49.441010 ug/L
EPA limit
PFOA
2019 to 2026
45065%0.731,4404 ng/L
EPA limit
PFOS
2019 to 2026
45048%01014 ng/L
EPA limit
Uranium
1999 to 2011
4881%1.6932030 ug/L
EPA limit
PFNA
2019 to 2026
45021%022010 ng/L
EPA limit
Nitrate
1957 to 2011
13945%039.710 mg/L
EPA limit
Lead
1999 to 2011
4815%03015 ug/L
EPA limit
PFHxS
2019 to 2026
45027%01910 ng/L
EPA limit
Fluoride
1957 to 2011
7278%0.33.34 mg/L
EPA limit
Radium (226 + 228)
1975 to 2000
12100%015 pCi/L
EPA limit
Copper
1999 to 2011
1070%0.0010.0291.3 mg/L
EPA limit
Manganese
1957 to 2011
no limit9158%10500300 ug/L
health guideline
Iron
1957 to 2011
no limit9179%5038,000300 ug/L
nuisance level
Chloride
1957 to 2011
no limit44100%15.1939250 mg/L
nuisance level

Sampled fewer than 10 times, too few to summarize: E. coli (8), Radon (4), Sodium (3).

Over time

Share of samples above the limit by period. A cell needs ten samples to show; a comparison needs twenty in each period. Later periods sample fewer wells, and often the ones already known to have a problem.

Contaminantbefore 20002000s2010s2020s
Nitrate3%38 samples1%93 samplesn/an/a
Fluoride0%25 samples0%43 samplesn/an/a

Nitrate, fluoride have held within a few points between the two most recent periods with enough samples.

Closer than the county

See the sampled wells near your address

The same records, drawn around one point: which wells within a few miles were sampled and what they found, how deep the wells next to you were drilled, and any leaking tank or cleanup site within a mile.

Check my address

What this means

Among homeowners in Kennebec County who sent a sample to the state lab, the health-based limits most often exceeded were arsenic (28% of 4,743 wells), uranium (6% of 4,005 wells), and fluoride (2% of 5,015 wells). These are ordinary wells tested by their owners, so the shares are the best available picture of a typical well here, with one caveat: people test more often when they suspect a problem.

What to test for in Kennebec County

  1. 1
    Arsenic
    90% of 114 local samples were above the limit.
  2. 2
    PFOA
    25% of 450 local samples were above the limit.
  3. 3
    PFOS
    12% of 450 local samples were above the limit.
  4. 4
    Uranium
    10% of 48 local samples were above the limit.
  5. 5
    PFNA
    4% of 450 local samples were above the limit.
  6. 6
    Fluoride
    2% of 5,015 local wells tested were above the Maine guideline.
  7. 7
    Nitrate
    2% of 139 local samples were above the limit.
  8. 8
    Lead
    2% of 48 local samples were above the limit.
  9. 9
    Volatile organic compounds (VOCs)
    174 leaking underground storage tank sites on record locally.
  10. 10
    PFAS
    29 unlined landfills on record locally.
  11. 11
    Metals panel
    55 hazardous waste sites on record locally.

Test your Kennebec County well for arsenic, PFOA and PFOS

Certified lab analysis of your own tap water, bottles and prepaid return shipping included. The Essential well panel covers arsenic, uranium, nitrate, lead, copper, manganese, iron, sodium and bacteria; radon and PFAS are add-ons.

Order the Tap Score well water test kit, from $209Already tested? Upload the report

Just want bacteria checked first? Tap Score coliform and E. coli test, $99. Coliform and E. coli are the tests every well needs every year.

Want a quick look before paying for a lab? Home well water test strips on Amazon check hardness, iron, pH and nitrate in minutes. They are a screen, not a result: arsenic, bacteria, uranium and PFAS need a certified lab.

Affiliate links: the merchant pays us a commission and the price is the same for you. It does not change what the data above says. As an Amazon Associate we earn from qualifying purchases.

Where to get a well tested in Maine: certified labs, state programs and prices.

Already have results back? Get your lab report read against the Kennebec County numbers, $29. Every line explained, ranked by what matters, with the fix for each.

Wells in Kennebec County

6,244 domestic wells in Kennebec County are on record with the state since 1970. 99% are drilled into bedrock, and the typical well is 240 feet deep (one in ten goes past 420 feet).

In a typical Kennebec County well, bedrock starts about 16 feet down, the median yield is 6.5 gallons per minute, 20% of wells yield under 3 gallons per minute and usually need a storage tank.

Bedrock wells are where arsenic, uranium and radon come from: the water sits in fractures in granite and metamorphic rock and picks up whatever the rock carries. That is why testing for those three matters more here than in a dug or gravel well.

570
1970s
326
1980s
843
1990s
1,467
2000s
1,228
2010s
1,355
2020s

The rock under Kennebec County

Not a principal aquifer

The USGS map places this area outside any principal aquifer, which usually means wells here draw from fractured bedrock or thin local deposits rather than a large regional aquifer. Bedrock wells of that kind are where arsenic, radon and uranium turn up, and yields vary from well to well.

Classification from the USGS Principal Aquifers of the United States (national map, 2003 edition, GIS release 2015), read at the county centroid. A single well can sit in a different unit, especially near a boundary.

Official help in Maine

Two places to start that are not selling anything: the state program that answers private well questions, and its list of labs certified to run drinking water tests. A certified lab is the difference between a result you can act on and a number.

Contamination sources on record in Kennebec County

Maine DEP records 174 leaking underground storage tank sites, 29 unlined landfills, and 55 hazardous waste sites in Kennebec County, among 439 regulated sites in total. Groundwater does not follow property lines, so a well within a few hundred feet of one of these is worth testing for what that site could release.

174
leaking underground storage tank sitesGasoline and heating oil that leaked from tanks move through groundwater as benzene, MTBE and other volatile organic compounds.
29
unlined landfillsOlder unlined landfills are a leading source of PFAS, VOCs and metals in nearby wells.
55
hazardous waste sitesSolvents, degreasers and metals from industrial sites can travel far in fractured bedrock.
181
other remediation projects

Treatment that fits the local profile

Arsenic

Point-of-use reverse osmosis; Adsorptive media (iron-based) whole-house; Anion exchange

Uranium

Point-of-use reverse osmosis; Anion exchange; Whole-house anion exchange

PFOA

Granular activated carbon whole-house; Point-of-use reverse osmosis; Anion exchange

PFOS

Granular activated carbon whole-house; Point-of-use reverse osmosis; Anion exchange

PFNA

Granular activated carbon whole-house; Point-of-use reverse osmosis; Anion exchange

Systems we would look at first

Some links below are affiliate links. If you buy through one, the merchant pays us a commission at no extra cost to you. It does not change which products we list or what the data says.

For arsenic

Under-sink reverse osmosis system

under-sink or countertop, about $300

Look for NSF/ANSI 58 certification listing the contaminant you need removed.

For arsenic

Whole-house arsenic and uranium filter

whole-house, at the point of entry, about $2,500

Adsorptive iron-based media; sized to your well yield.

For arsenic

Aquasana SmartFlow reverse osmosis

under-sink or countertop, about $225

Certified to NSF/ANSI 58 and 53 to reduce arsenic (96%, pentavalent), fluoride (90%), lead (99%), nitrate, nitrite and PFOA/PFOS at the kitchen tap, with a remineralizer.

For PFOA

Aquasana Claryum 3-Stage under-sink filter

under-sink or countertop, about $175

Certified to NSF/ANSI 53 to reduce 99% of lead and 99.7% of PFOA and PFOS at the tap. Not a fix for arsenic, nitrate or bacteria.

For PFOA

Whole-house PFAS carbon system

whole-house, at the point of entry, about $3,000

Granular activated carbon certified to NSF/ANSI 53 for PFOA and PFOS; replace media on schedule.

For PFOA

Aquasana HealthShield whole-house filter

whole-house, at the point of entry, about $2,099

Whole-house carbon system the maker certifies to reduce PFAS (PFOA and PFOS) and VOCs at every tap; a UV option adds bacteria protection.

Free, no obligation

Get on the list for a free in-home water test in Kennebec County

No water treatment company serves Kennebec County through Well Water Nerd yet. We are signing licensed companies on county by county: they test at your tap for free, walk you through the numbers, and quote treatment only if something needs fixing. Leave your details and you are first in line. Nothing is shared until a company joins for Kennebec County, and you get an email naming it first.

What are you worried about?

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Common questions

How deep are wells in Kennebec County?

The typical domestic well in Kennebec County is 240 feet deep, based on 6,244 wells reported to the state since 1970. One in ten is deeper than 420 feet. 99% are drilled into bedrock.

Is there arsenic in well water in Kennebec County?

Arsenic was detected in 99% of 114 public well samples in Kennebec County, and 90% were above the EPA limit of 10 ug/L. Arsenic has no taste or smell; a lab test is the only way to know your level.

How often should I test a private well in Kennebec County?

Test for bacteria and nitrate every year. Test once for arsenic, uranium, radon, fluoride, manganese and PFAS, then again every three to five years or after any change in taste, color, or plumbing.

Towns in Kennebec County

2 towns have fewer than 30 public samples and are included in the Kennebec County totals above rather than shown separately: Randolph, Unity UT.

Counties near Kennebec County

Closest first. Groundwater does not stop at a line on a map, so the next county over is a fair second opinion.

Want the numbers themselves? Download the Maine dataset as CSV, every county and town, with the sources named.

Sources

  • Maine DEP PFAS investigation: 1,800 samples in Kennebec County. PFAS results for private wells sampled by the Maine Department of Environmental Protection. Retrieved September 3, 2026.
  • USGS Water Quality Portal: 684 samples in Kennebec County. Data from the Water Quality Portal, a service of USGS, EPA and USDA; groundwater samples collected by USGS and cooperators. Retrieved September 3, 2026.
  • Maine Tracking Network private well summaries: summaries for 6 contaminants in Kennebec County, up to 5,244 wells each. Town summaries of private well tests run by the Maine Health and Environmental Testing Laboratory, published by Maine CDC through the Maine Tracking Network. Shares are against Maine's guideline for each analyte (arsenic 10 ug/L, uranium 30 ug/L, fluoride 2 mg/L, manganese 0.3 mg/L, nitrate 10 mg/L, nitrite 1 mg/L). Towns with too few tests are suppressed (NR). Only the share above the guideline and wells tested are published; no medians. Retrieved September 3, 2026.
  • USGS national arsenic model (Ayotte 2017): estimated share of 65,729 people on private wells in Kennebec County above 10 ug/L of arsenic, from geology, well depth and land use. County estimates of domestic well users with arsenic above 10 ug/L from the USGS national logistic regression model (Ayotte, Medalie and Qi, 2017), with private well population from the USGS 2015 county water-use compilation (Dieter and others, 2018). Retrieved September 15, 2026.
  • Maine Geological Survey well database: 6,501 well records in Kennebec County, 6,244 domestic. Well construction records reported to the Maine Geological Survey by licensed well drillers. Only aggregates are shown; owner names and addresses are never stored. Retrieved September 3, 2026.
  • Maine DEP regulated sites: 439 regulated sites located in Kennebec County. Remediation sites, leaking underground storage tanks and closed municipal landfills from the Maine Department of Environmental Protection. Retrieved September 3, 2026.

Non-detects count as samples and are treated as zero when computing medians. Exactly at the limit counts as not above it. A sample belongs to the town containing the well's reported coordinates.