Well Water Nerd

Well water in Salem County, New Jersey

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Testing recommended

private wells tested between 2002 and 2024 in Salem County had total coliform above the New Jersey limit (any detection), according to NJDEP.

The strongest signal is PFOA: 67% of 24 local samples were above the limit, too few samples to carry the headline but first on the test list below.

5,094 private wells tested 2002 to 2024 in state summaries; 2,003 test results across 14 contaminants from at least 196 wells, 1950 to 2026; sodium has the most at 448. Data refreshed September 15, 2026.

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

An estimated 21,913 people in Salem County get their drinking water from a private well, per USGS 2015 county water use. That is about 34% of residents.

Separately, the USGS national arsenic model estimates that 7% of the 21,913 people on private wells in Salem County draw water above 10 ug/L (the model's range is 5% to 11%), from geology and well depth rather than local tests.

What homeowner tests found

NJDEP Private Well Testing Act summaries: private wells tested and reported to the state, 2002 to 2024. Shares are against the level the state applies to each contaminant, named in the last column; several are stricter than EPA.

ContaminantAbove state levelWells testedMedian95th pctHighestState level
Iron5,093300 ug/L
Manganese5,09450 ug/L
Gross alpha4,95015 pCi/L
Total coliform5,046
Nitrate5,09410 mg/L
PFOA95114 ng/L
PFOS95113 ng/L
E. coli
Fecal coliform or
5,044
PFNA95113 ng/L
Arsenic2,0565 ug/L

What individual samples found

Each row summarizes every public sample for that contaminant inside Salem 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
PFOA
2020 to 2023
2479%10.51104 ng/L
EPA limit
Nitrate
1973 to 2026
25185%5.6239.110 mg/L
EPA limit
PFOS
2020 to 2023
2438%0174 ng/L
EPA limit
Radium (226 + 228)
1988 to 2021
8180%0.97135 pCi/L
EPA limit
Arsenic
1975 to 2025
18048%0710 ug/L
EPA limit
Lead
1975 to 2023
16740%01015 ug/L
EPA limit
Uranium
1988 to 2022
3964%0.040.3630 ug/L
EPA limit
Sodium
1950 to 2025
no limit448100%24.91,90020 mg/L
health guideline
Iron
1950 to 2025
no limit36288%380118,000300 ug/L
nuisance level
Manganese
1950 to 2025
no limit35899%35.58,000300 ug/L
health guideline
Radon
1988 to 2024
no limit5798%4501,8402,000 pCi/L
health guideline

Sampled fewer than 10 times, too few to summarize: Fluoride (6), Copper (4), Chloride (2).

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
Nitrate33%175 samples45%31 samples30%23 samples45%22 samples
Arsenic0%66 samples0%37 samples0%29 samples0%48 samples
Lead0%104 samples0%21 samples0%22 samples0%20 samples
Radium (226 + 228)11%66 samples0%10 samplesn/an/a

Nitrate above the limit in Salem County rose from 30% of 23 samples in the 2010s to 45% of 22 in the 2020s.

Arsenic, lead 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 Salem County who sent a sample to the state lab, the health-based limits most often exceeded were total coliform (11% of 5,046 wells), nitrate (9% of 5,094 wells), and PFOA (6% of 951 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.

Iron and manganese exceed the state's advisory level in a sizable share of wells; these are mostly a taste, staining or diet issue rather than a toxicity one.

What to test for in Salem County

  1. 1
    PFOA
    67% of 24 local samples were above the limit.
  2. 2
    Nitrate
    35% of 251 local samples were above the limit.
  3. 3
    PFOS
    17% of 24 local samples were above the limit.
  4. 4
    Total coliform
    11% of 5,046 local wells tested were above the New Jersey limit (any detection).
  5. 5
    Radium (226 + 228)
    9% of 81 local samples were above the limit.
  6. 6
    E. coli
    <1% of 5,044 local wells tested were above the New Jersey limit (any detection).
  7. 7
    PFNA
    <1% of 951 local wells tested were above the New Jersey limit.
  8. 8
    Arsenic
    <1% of 2,056 local wells tested were above the New Jersey limit.
  9. 9
    Volatile organic compounds (VOCs)
    1 hazardous waste site on record locally.
  10. 10
    Metals panel
    1 hazardous waste site on record locally.

Test your Salem County well for PFOA, nitrate 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 New Jersey: certified labs, state programs and prices.

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

The rock under Salem County

Northern Atlantic Coastal Plain aquifer system

Semiconsolidated sand. Coastal plain sands like these give steady yields at moderate depth. Salt water and sodium are the usual issues near the coast, and nitrate where the water table is shallow; arsenic and radon from bedrock are less common.

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 New Jersey

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 Salem County

NJDEP records 1 hazardous waste site in Salem County, among 517 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.

1
hazardous waste siteSolvents, degreasers and metals from industrial sites can travel far in fractured bedrock.
389
registered underground storage tank sitesRegistered tanks are regulated and inspected; they matter most when they are old or near a shallow well.
15
lined landfills and transfer facilities
112
other remediation projects

Treatment that fits the local profile

Total coliform

Inspect and repair the well cap and casing, then shock chlorinate and retest; UV disinfection whole-house; Chlorination system

Nitrate

Point-of-use reverse osmosis; Anion exchange; Distillation

PFOA

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

Gross alpha

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

Iron

Oxidizing filter whole-house; Water softener (low levels); Aeration plus filtration

PFOS

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 total coliform

Aquasana Rhino Well Water with UV

whole-house, at the point of entry, about $2,871

Whole-house system built for wells: sediment pre-filter, KDF and carbon, and a UV lamp rated to kill 99.99% of bacteria and viruses. It does not remove arsenic, nitrate, uranium or radon.

For nitrate

Under-sink reverse osmosis system

under-sink or countertop, about $300

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

For nitrate

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 Salem County

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

What are you worried about?

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Common questions

Is there arsenic in well water in Salem County?

Arsenic was detected in 48% of 180 public well samples in Salem County, and 0% 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 high is radon in well water in Salem County?

The median radon level across 57 public samples in Salem County was 450 pCi/L, with a high of 1,840 pCi/L. New Hampshire recommends treatment above 2,000 pCi/L.

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

3 towns have fewer than 30 public samples and are included in the Salem County totals above rather than shown separately: Elmer borough, Penns Grove borough, Woodstown borough.

Counties near Salem 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 New Jersey dataset as CSV, every county and town, with the sources named.

Sources

  • USGS Water Quality Portal: 2,003 samples in Salem 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.
  • NJDEP Private Well Testing Act summaries: summaries for 10 contaminants in Salem County, up to 5,094 wells each. Share of private wells exceeding each standard in tests required at sale or lease under the New Jersey Private Well Testing Act, September 2002 to December 2024, published by NJDEP. Tests are untreated water at the time of sale or lease, so every well is counted once per transaction. Municipalities with fewer than ten wells are suppressed. Standards are New Jersey's: arsenic 5 ug/L, PFOA 14 ng/L, PFOS 13 ng/L, PFNA 13 ng/L, manganese and iron secondary standards. Uranium and PFAS were added to the required panel in 2021 and 2020, so their well counts are smaller. Retrieved September 9, 2026.
  • USGS national arsenic model (Ayotte 2017): estimated share of 21,913 people on private wells in Salem 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.
  • NJDEP regulated sites: 517 regulated sites located in Salem County. Known Contaminated Sites, regulated underground storage tank facilities and solid waste landfills from the New Jersey Department of Environmental Protection (NJ-GeoWeb). Retrieved September 9, 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.