Nitrate in New Jersey well water
In New Jersey, 3% of 141,301 private wells tested between 2002 and 2024 had nitrate above the New Jersey limit (10 mg/L), according to NJDEP.
Nitrate reaches wells from fertilizer, septic systems and manure. Above the limit it can cause methemoglobinemia (blue baby syndrome) in infants under six months, and long-term exposure is associated with some cancers. Shallow and dug wells near farmland or dense septic systems are most at risk.
Check your nitrate number
Type the value from your lab report. It is compared to the New Jersey limit and the EPA limit, the same way the full interpretation does it.
Test your New Jersey well for 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 $209Already tested? Upload the report
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Systems that remove nitrate
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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 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.
Rather have it installed and sized for your well? Book a free in-home water test with a licensed local company.
Where to get a well tested for nitrate in New Jersey: certified labs, state programs and prices.
By county, from homeowner tests
Share of private wells above the state guidance level (10 mg/L) in tests homeowners sent to the state lab, 2002 to 2024.
| County | Above state level | Wells tested | Highest |
|---|---|---|---|
| Cumberland | 8,423 | ||
| Salem | 5,094 | ||
| Passaic | 5,838 | ||
| Sussex | 14,792 | ||
| Middlesex | 1,222 | ||
| Atlantic | 8,102 | ||
| Gloucester | 9,219 | ||
| Warren | 7,035 | ||
| Cape May | 7,348 | ||
| Morris | 13,110 | ||
| Camden | 3,759 | ||
| Mercer | 3,471 | ||
| Union | 84 | ||
| Burlington | 12,189 | ||
| Essex | 231 |
Towns with the highest share above the state level
- Buena borough, Atlantic County52% of 46 wells
- Plainsboro township, Middlesex County40% of 43 wells
- Shiloh borough, Cumberland County29% of 103 wells
- Deerfield township, Cumberland County26% of 622 wells
- Vineland, Cumberland County26% of 1,188 wells
- Upper Deerfield township, Cumberland County25% of 1,081 wells
- Cranbury township, Middlesex County21% of 96 wells
- Upper Pittsgrove township, Salem County19% of 521 wells
- Hopewell township, Cumberland County16% of 772 wells
- Pittsgrove township, Salem County15% of 1,418 wells
- Ringwood borough, Passaic County14% of 679 wells
- Franklin township, Warren County12% of 372 wells
- Stow Creek township, Cumberland County12% of 241 wells
- Pennsville township, Salem County10% of 39 wells
- Buena Vista township, Atlantic County10% of 1,194 wells
- Mannington township, Salem County9% of 215 wells
- Hopatcong borough, Sussex County9% of 2,184 wells
- Greenwich township, Cumberland County9% of 164 wells
- Greenwich township, Warren County9% of 245 wells
- Hammonton, Atlantic County8% of 463 wells
- Fairfield township, Cumberland County8% of 748 wells
- West Windsor township, Mercer County8% of 146 wells
- Harmony township, Warren County7% of 429 wells
- Oldmans township, Salem County7% of 221 wells
- Alloway township, Salem County7% of 669 wells
By county, from individual samples
Public monitoring samples against the EPA limit (10 mg/L); counties with at least 30 samples.
| County | Above EPA limit | Samples | Detected | Median | Highest |
|---|---|---|---|---|---|
| Salem | 251 | 85% | 5.62 | 39.1 mg/L | |
| Cumberland | 314 | 81% | 3.63 | 38.3 mg/L | |
| Mercer | 205 | 88% | 1.8 | 72.4 mg/L | |
| Somerset | 72 | 82% | 2.42 | 11.4 mg/L | |
| Warren | 142 | 83% | 1.69 | 16.1 mg/L | |
| Middlesex | 384 | 55% | 0.14 | 28 mg/L | |
| Gloucester | 764 | 74% | 1.18 | 55.5 mg/L | |
| Sussex | 187 | 85% | 0.89 | 28.3 mg/L | |
| Atlantic | 300 | 60% | 0.22 | 31 mg/L | |
| Burlington | 445 | 63% | 0.03 | 26 mg/L | |
| Cape May | 163 | 44% | 0 | 23 mg/L | |
| Monmouth | 214 | 34% | 0 | 20.9 mg/L | |
| Ocean | 565 | 71% | 0.06 | 85 mg/L | |
| Camden | 428 | 72% | 0.395 | 31.2 mg/L | |
| Bergen | 194 | 86% | 2.1 | 11 mg/L |
Sources
- NJDEP Private Well Testing Act summaries: 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.
- Individual samples from the USGS Water Quality Portal and state monitoring, summarized per geography. nitrate counts and shares are listed on each county and town page with their sources.
Analysis: Nitrate in private wells, decade by decade, from the same public records.