What was found in North Hempstead's water
The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate-Nitrite | 5783 µg/L 58% of the EPA limit 10000 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 8976 µg/L — WESTBURY WD · 20,500 people · 2019 | 8/8 | SYR4 |
| Nitrate | 5760.5 µg/L 58% of the EPA limit 10000 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 8900 µg/L — WESTBURY WD · 20,500 people · 2019 | 8/8 | SYR4 |
| Nitrite | 147 µg/L 15% of the EPA limit 1000 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 2473 µg/L — WA OF GREAT NECK NORTH · 31,400 people · 2019 | 4/8 | SYR4 |
| Copper | 143.5 µg/L 11% of the EPA limit 1300 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 360 µg/L — WESTBURY WD · 20,500 people · 2019 | 8/8 | SYR4 |
| Fluoride | 127 µg/L 3.2% of the EPA limit 4000 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 235 µg/L — PORT WASHINGTON WD · 34,000 people · 2019 | 7/8 | SYR4 |
| Barium | 62.05 µg/L 3.1% of the EPA limit 2000 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 66.33 µg/L — WA OF GREAT NECK NORTH · 31,400 people · 2019 | 8/8 | SYR4 |
| cis-1,2-Dichloroethylene | 23.41 µg/L 33% of the EPA limit 70 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 5/8 | SYR4 |
| Arsenic | 17.6 µg/L 176% of the EPA limit, at the 95th percentile of samples — 10 µg/L Highest in the city: WA OF GREAT NECK NORTH · 31,400 people · 2019 | 1/8 | SYR4 |
| Tetrachloroethylene | 16.94 µg/L 339% of the EPA limit, at the 95th percentile of samples — 5 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 17.51 µg/L — PORT WASHINGTON WD · 34,000 people · 2019 | 7/8 | SYR4 |
| Cyanide | 16.8 µg/L 8.4% of the EPA limit 200 µg/L Highest in the city: WA OF GREAT NECK NORTH · 31,400 people · 2019 | 1/8 | SYR4 |
| TTHM | 12.21 µg/L 15% of the EPA limit 80 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 6/8 | SYR4 |
| Toluene | 11.3 µg/L 1.1% of the EPA limit 1000 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 4/8 | SYR4 |
| Trichloroethylene | 10.035 µg/L 201% of the EPA limit, at the 95th percentile of samples — 5 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 7/8 | SYR4 |
| Beryllium, Total | 10 µg/L 250% of the EPA limit, at the 95th percentile of samples — 4 µg/L Highest in the city: WA OF GREAT NECK NORTH · 31,400 people · 2019 | 2/8 | SYR4 |
| Combined Radium (-226 And -228) | 4.67 pCi/L 93% of the EPA limit 5 pCi/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 8.8544 pCi/L — MANHASSET LAKEVILLE WD · 43,000 people · 2019 | 8/8 | SYR4 |
| Lead | 4.77 µg/L 32% of the EPA limit 15 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 8.242 µg/L — MANHASSET LAKEVILLE WD · 43,000 people · 2019 | 8/8 | SYR4 |
| 1,1-Dichloroethylene | 7.5 µg/L 107% of the EPA limit, at the 95th percentile of samples — 7 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 7/8 | SYR4 |
| Combined Uranium | 7.06016 µg/L 24% of the EPA limit 30 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 8/8 | SYR4 |
| Bromoform | 5.9 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 6/8 | SYR4 |
| Selenium | 2.86 µg/L 5.7% of the EPA limit 50 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 5.815 µg/L — WA OF GREAT NECK NORTH · 31,400 people · 2019 | 5/8 | SYR4 |
| Gross Beta Particle Activity | 5.658 pCi/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 8/8 | SYR4 |
| Dibromochloromethane | 4.1 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 5/8 | SYR4 |
| Gross Alpha, Excl. Radon And U | 2.19 pCi/L 15% of the EPA limit 15 pCi/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 3.924 pCi/L — WESTBURY WD · 20,500 people · 2019 | 6/8 | SYR4 |
| Total Haloacetic Acids (HAA5) | 3.835 µg/L 6.4% of the EPA limit 60 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2018 | 3/8 | SYR4 |
| Chromium | 3.261 µg/L 3.3% of the EPA limit 100 µg/L Highest in the city: PORT WASHINGTON WD · 34,000 people · 2019 | 2/8 | SYR4 |
| Chloroform | 3.26 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 6/8 | SYR4 |
| 1,1,2-Trichloroethane | 3 µg/L 60% of the EPA limit 5 µg/L Highest in the city: ALBERTSON WD · 13,500 people · 2019 | 4/8 | SYR4 |
| Monochloroacetic Acid | 3 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2018 | 1/8 | SYR4 |
| Trichloroacetic Acid | 2.98 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2018 | 1/8 | SYR4 |
| Bromodichloromethane | 1.605 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 2.975 µg/L — SANDS POINT (V) · 2,900 people · 2019 | 5/8 | SYR4 |
| Dibromoacetic Acid | 2.94 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2018 | 3/8 | SYR4 |
| 1,1,1-Trichloroethane | 1.7 µg/L 0.9% of the EPA limit 200 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 2.79 µg/L — PORT WASHINGTON WD · 34,000 people · 2019 | 7/8 | SYR4 |
| 2,4-D | 2.6 µg/L 3.7% of the EPA limit 70 µg/L Highest in the city: PORT WASHINGTON WD · 34,000 people · 2019 | 1/8 | SYR4 |
| Carbon Tetrachloride | 2.02 µg/L 40% of the EPA limit 5 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 2.381 µg/L — PORT WASHINGTON WD · 34,000 people · 2019 | 4/8 | SYR4 |
| Thallium, Total | 0.3400 µg/L 17% of the EPA limit 2 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 1.8755 µg/L — WESTBURY WD · 20,500 people · 2019 | 2/8 | SYR4 |
| Vinyl Chloride | 1.8 µg/L 90% of the EPA limit 2 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 2/8 | SYR4 |
| Cadmium | 1.62 µg/L 32% of the EPA limit 5 µg/L Highest in the city: WESTBURY WD · 20,500 people · 2019 | 2/8 | SYR4 |
| Chlorobenzene | 1.4975 µg/L 1.5% of the EPA limit 100 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 1/8 | SYR4 |
| Antimony, Total | 1.373 µg/L 23% of the EPA limit 6 µg/L Highest in the city: WESTBURY WD · 20,500 people · 2019 | 2/8 | SYR4 |
| Dichloroacetic Acid | 1.1 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2018 | 1/8 | SYR4 |
| 1,2-Dichloroethane | 0.7490 µg/L 15% of the EPA limit 5 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 0.9800 µg/L — PORT WASHINGTON WD · 34,000 people · 2019 | 3/8 | SYR4 |
| Dichloromethane | 0.6425 µg/L 13% of the EPA limit 5 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 0.8270 µg/L — ALBERTSON WD · 13,500 people · 2019 | 2/8 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 0.7600 µg/L 13% of the EPA limit 6 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 4/8 | SYR4 |
| Chlordane | 0.7460 µg/L 37% of the EPA limit 2 µg/L Highest in the city: PORT WASHINGTON WD · 34,000 people · 2019 | 2/8 | SYR4 |
| P-Dichlorobenzene | 0.7000 µg/L 0.9% of the EPA limit 75 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 1/8 | SYR4 |
| Mercury | 0.5900 µg/L 30% of the EPA limit 2 µg/L Highest in the city: WA OF GREAT NECK NORTH · 31,400 people · 2019 | 1/8 | SYR4 |
| trans-1,2-Dichloroethylene | 0.5900 µg/L 0.6% of the EPA limit 100 µg/L Highest in the city: CARLE PLACE WD · 9,005 people · 2019 | 1/8 | SYR4 |
| Pentachlorophenol | 0.1167 µg/L 12% of the EPA limit 1 µg/L Highest in the city: WESTBURY WD · 20,500 people · 2019 | 2/8 | SYR4 |
| Heptachlor Epoxide | 0.0435 µg/L 22% of the EPA limit 0.2000 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019
Highest in the city: 0.0783 µg/L — PORT WASHINGTON WD · 34,000 people · 2019 | 3/8 | SYR4 |
| Endrin | 0.0630 µg/L 3.2% of the EPA limit 2 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 1/8 | SYR4 |
| Ethylene Dibromide | 0.0300 µg/L 60% of the EPA limit 0.0500 µg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2019 | 3/8 | SYR4 |
| PFNA | 0.0190 µg/L No EPA limit set Highest in the city: MANHASSET LAKEVILLE WD · 43,000 people · 2025 | 3/8 | UCMR-5 |
| PFOA | 0.0100 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2024
Highest in the city: 0.0120 µg/L — ALBERTSON WD · 13,500 people · 2025 | 5/8 | UCMR-5 |
| Pfpea | 0.0095 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2024 | 5/8 | UCMR-5 |
| Pfhxa | 0.0074 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2024 | 5/8 | UCMR-5 |
| Pfba | 0.0071 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2024 | 2/8 | UCMR-5 |
| PFOS | 0.0061 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2024
Highest in the city: 0.0069 µg/L — ALBERTSON WD · 13,500 people · 2025 | 3/8 | UCMR-5 |
| 6:2 Fts | 0.0065 µg/L No EPA limit set Highest in the city: PORT WASHINGTON WD · 34,000 people · 2025 | 1/8 | UCMR-5 |
| PFHXS | 0.0045 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2024 | 2/8 | UCMR-5 |
| PFBS | 0.0036 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2024 | 1/8 | UCMR-5 |
| Pfhpa | 0.0034 µg/L No EPA limit set Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2024 | 2/8 | UCMR-5 |
| Lead | 0.0014 mg/L 9.3% of the EPA limit 0.0150 mg/L Main supplier: WA OF WESTERN NASSAU · 120,000 people · 2024
Highest in the city: 0.0030 mg/L — WA OF GREAT NECK NORTH · 31,400 people · 2025 | 8/8 | LCR |
Each bar shows the measured level as a share of the EPA limit: green is
well under, amber is close to it, red is over. For lead and copper the
limit applies to exactly the 90th-percentile figure shown, so red there
means a real exceedance. For everything else the limit applies to a
running annual average while the figure is the 95th percentile of the
system's samples — over 100% is worth reading, but is not by itself a
violation.
Formal violations are listed separately.
These are the utilities' own EPA-reported results, not a city-wide
average. A detection means the lab measured the
substance — it isn't the same as exceeding a legal limit. Hover a source
tag to see the EPA program and years behind each figure.
Water suppliers serving North Hempstead
| Supplier | Population served |
|---|---|
| WA OF WESTERN NASSAU | 120,000 |
| MANHASSET LAKEVILLE WD | 43,000 |
| PORT WASHINGTON WD | 34,000 |
| WA OF GREAT NECK NORTH | 31,400 |
| WESTBURY WD | 20,500 |
| ALBERTSON WD | 13,500 |
| CARLE PLACE WD | 9,005 |
| SANDS POINT (V) | 2,900 |
Frequently asked questions about North Hempstead tap water
Is North Hempstead tap water safe to drink?
EPA testing detected 62 contaminants in the water serving North Hempstead. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.
How many water suppliers serve North Hempstead?
8 public water suppliers report drinking-water monitoring for North Hempstead, New York to the EPA. Each is listed above with its population served.
What contaminants are in North Hempstead's water?
The contaminants EPA monitoring detected in North Hempstead include Nitrate-Nitrite, Nitrate, Nitrite, Copper, Fluoride. The full list, with the level at the main supplier and the data source, is in the table above.
Where does this data come from?
Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.