Well Water Nerd

Well water in Falmouth, Maine

In Falmouth, 27% of 144 private wells tested had uranium above the Maine guideline (30 ug/L), according to Maine CDC.

207 private wells tested in state summaries; 72 individual samples from 72 wells, 1975 to 2026. Data refreshed September 3, 2026.

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, 18% of 72 PFOA results in Falmouth were above the EPA limit of 4 ng/L. In that targeted sampling, 13% of 72 PFOS results in Falmouth were above the EPA limit of 4 ng/L.

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.

ContaminantWells testedAbove state levelMedian95th pctHighestState level
Uranium14427%30 ug/L
Arsenic14915%10 ug/L
Manganese1364%300 ug/L
Fluoride2071%2 mg/L
Nitrate1630%10 mg/L
Nitrite1630%1 mg/L

What individual samples found

Each row summarizes every public sample for that contaminant inside Falmouth. 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.

ContaminantSamplesDetectedAbove limitMedianHighestLimit
PFOA
2022 to 2026
7261%18%0.5221214 ng/L
EPA limit
PFOS
2022 to 2026
7260%13%0.68491.84 ng/L
EPA limit
PFHxS
2022 to 2026
7251%3%0.3592410 ng/L
EPA limit
PFNA
2022 to 2026
7210%0%07.6910 ng/L
EPA limit

Sampled fewer than 10 times, too few to summarize: Fluoride (1), Nitrate (3), Radium (226 + 228) (2), Chloride (2), Manganese (1).

Get the free Falmouth well report

One email with the numbers above, what they mean for a home in Falmouth, exactly which tests to order, and what treatment fits the local profile. No spam, unsubscribe in one click.

What this means

Among homeowners in Falmouth who sent a sample to the state lab, the health-based limits most often exceeded were uranium (27% of 144 wells), arsenic (15% of 149 wells), and fluoride (1% of 207 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 Falmouth

  • Volatile organic compounds (VOCs)4 leaking underground storage tank sites on record locally.
  • PFAS2 unlined landfills on record locally.
  • Metals panel2 hazardous waste sites on record locally.
  • Uranium27% of 144 local wells tested were above the Maine guideline.
  • PFOA18% of 72 local samples were above the limit.
  • Arsenic15% of 149 local wells tested were above the Maine guideline.
  • PFOS13% of 72 local samples were above the limit.
  • Manganese4% of 136 local wells tested were above the Maine guideline.
  • PFHxS3% of 72 local samples were above the limit.
  • Fluoride1% of 207 local wells tested were above the Maine guideline.
  • Coliform bacteriaRecommended for every private well, every year.

Wells in Falmouth

445 domestic wells in Falmouth are on record with the state since 1970. 100% are drilled into bedrock, and the typical well is 380 feet deep (one in ten goes past 700 feet).

In a typical Falmouth well, bedrock starts about 10 feet down, the median yield is 6 gallons per minute, 28% 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.

25
1970s
40
1980s
95
1990s
80
2000s
89
2010s
84
2020s

Contamination sources on record in Falmouth

Maine DEP records 4 leaking underground storage tank sites, 2 unlined landfills, and 2 hazardous waste sites in Falmouth, among 16 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.

4
leaking underground storage tank sitesGasoline and heating oil that leaked from tanks move through groundwater as benzene, MTBE and other volatile organic compounds.
2
unlined landfillsOlder unlined landfills are a leading source of PFAS, VOCs and metals in nearby wells.
2
hazardous waste sitesSolvents, degreasers and metals from industrial sites can travel far in fractured bedrock.
8
other remediation projects

Treatment that fits the local profile

Uranium
Point-of-use reverse osmosis; Anion exchange; Whole-house anion exchange
Arsenic
Point-of-use reverse osmosis; Adsorptive media (iron-based) whole-house; Anion exchange
Fluoride
Point-of-use reverse osmosis; Activated alumina; Distillation
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
PFHxS
Granular activated carbon whole-house; Point-of-use reverse osmosis; Anion exchange

Book a free water test in Falmouth

A licensed local water treatment company tests your tap water in your home, walks you through the numbers, and quotes treatment only if something needs fixing. Free, about 30 minutes, no obligation.

What are you worried about?

The test is free and there is no obligation. Your details go only to the company named above, and we log the time and address of this request.

Common questions

How deep are wells in Falmouth?

The typical domestic well in Falmouth is 380 feet deep, based on 445 wells reported to the state since 1970. One in ten is deeper than 700 feet. 100% are drilled into bedrock.

How often should I test a private well in Falmouth?

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.

Sources

  • Maine DEP PFAS investigation: 288 samples in Falmouth. PFAS results for private wells sampled by the Maine Department of Environmental Protection. Retrieved September 3, 2026.
  • USGS Water Quality Portal: 9 samples in Falmouth. 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 Falmouth, up to 207 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.
  • Maine Geological Survey well database: 464 well records in Falmouth, 445 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: 16 regulated sites located in Falmouth. 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.