Well water in Addison County, Vermont

In Addison County, 2% of 1,835 private wells tested had arsenic above the Vermont limit (10 ug/L), according to the Vermont Department of Health.

2,022 private wells tested in state summaries; 23 test results across 10 contaminants from at least 3 wells, 1966 to 1995; nitrate has the most at 4. Data refreshed September 15, 2026.

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

An estimated 23,708 people in Addison County get their drinking water from a private well, per USGS 2015 county water use. That is about 64% of residents.

Separately, the USGS national arsenic model estimates that 2% of the 23,708 people on private wells in Addison County draw water above 10 ug/L (the model's range is 2% to 3%), from geology and well depth rather than local tests.

What homeowner tests found

Vermont Tracking 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.

Contaminant	Above state level	Wells tested	Highest	State level
Gross alpha Gross Alpha	5%	1,051	80.7	15 pCi/L
Arsenic	2%	1,835	72	10 ug/L
Uranium	<1%	1,733	621	20 ug/L
Nitrate	<1%	2,022	17	10 mg/L
Fluoride	<1%	1,833	15.7	4 mg/L
Radon	0%	22	1,100	4,000 pCi/L

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.

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What this means

Among homeowners in Addison County who sent a sample to the state lab, the health-based limits most often exceeded were arsenic (2% of 1,835 wells), uranium (<1% of 1,733 wells), and nitrate (<1% of 2,022 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 Addison County

1
Arsenic
2% of 1,835 local wells tested were above the Vermont limit.
2
Uranium
<1% of 1,733 local wells tested were above the Vermont limit.
3
Nitrate
<1% of 2,022 local wells tested were above the Vermont limit.
4
Fluoride
<1% of 1,833 local wells tested were above the Vermont limit.
5
Coliform bacteria
Recommended for every private well, every year.
6
Gross alpha
5% of 1,051 local wells tested were above the Vermont limit.
7
Radon
Median local reading is 490 pCi/L.
8
Iron
Detected in 100% of local samples.
9
Volatile organic compounds (VOCs)
222 leaking underground storage tank sites on record locally.
10
PFAS
6 unlined landfills on record locally.
11
Metals panel
40 hazardous waste sites on record locally.

Test your Addison County well for arsenic, uranium and nitrate

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 $209 Already 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 Vermont: certified labs, state programs and prices.

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

Wells in Addison County

3,036 domestic wells in Addison County are on record with the state since 1975. 93% are drilled into bedrock, and the typical well is 350 feet deep (one in ten goes past 625 feet).

In a typical Addison County well, bedrock starts about 32 feet down, the median yield is 10 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.

561

1990s

1,367

2000s

618

2010s

458

2020s

The rock under Addison 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 Vermont

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.

Drinking Water, Vermont Department of Health
Certification Programs for Other Labs, Vermont Department of Health

Contamination sources on record in Addison County

Vermont ANR records 222 leaking underground storage tank sites, 6 unlined landfills, 40 hazardous waste sites, and 9 reported spills and releases in Addison County, among 395 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.

222: leaking underground storage tank sitesGasoline and heating oil that leaked from tanks move through groundwater as benzene, MTBE and other volatile organic compounds.
6: unlined landfillsOlder unlined landfills are a leading source of PFAS, VOCs and metals in nearby wells.
40: hazardous waste sitesSolvents, degreasers and metals from industrial sites can travel far in fractured bedrock.
9: reported spills and releasesMost spills are fuel; a few are solvents or chemicals that reach the water table.
118: registered underground storage tank sitesRegistered tanks are regulated and inspected; they matter most when they are old or near a shallow well.

Treatment that fits the local profile

Gross alpha

Point-of-use reverse osmosis; Water softener (cation exchange) for radium; Anion exchange for uranium

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 gross alpha

Under-sink reverse osmosis system

under-sink or countertop, about $300

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

Free, no obligation

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

No water treatment company serves Addison 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 Addison County, and you get an email naming it first.

Common questions

How deep are wells in Addison County?

The typical domestic well in Addison County is 350 feet deep, based on 3,036 wells reported to the state since 1975. One in ten is deeper than 625 feet. 93% are drilled into bedrock.

How often should I test a private well in Addison 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 Addison County

7 towns have fewer than 30 public samples and are included in the Addison County totals above rather than shown separately: Addison, Bridport, Goshen, Granville, Panton, Vergennes, Whiting.

Counties near Addison 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 Vermont dataset as CSV, every county and town, with the sources named.

Sources

USGS Water Quality Portal: 23 samples in Addison 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.
Vermont Tracking private well summaries: summaries for 6 contaminants in Addison County, up to 2,022 wells each. Town summaries of private well tests reported to the Vermont Department of Health, published through Vermont Environmental Public Health Tracking. Shares are against the limit Vermont applies to each analyte: arsenic 10 ug/L, uranium 20 ug/L (stricter than EPA), fluoride 4 mg/L, nitrate 10 mg/L, gross alpha 15 pCi/L, radon 4,000 pCi/L advisory. Only towns with 20 or more results are published; statistics below the reporting limit show as *. Retrieved September 3, 2026.
USGS national arsenic model (Ayotte 2017): estimated share of 23,708 people on private wells in Addison 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.
Vermont ANR well completion reports: 3,195 well records in Addison County, 3,036 domestic. Well completion reports filed with the Vermont Agency of Natural Resources since 1966. Only aggregates are shown; owner names and addresses are never stored. Retrieved September 3, 2026.
Vermont ANR regulated sites: 395 regulated sites located in Addison County. Hazardous waste sites, landfills and underground storage tanks from the Vermont Agency of Natural Resources. 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.