What was found in 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 | 132 µg/L 1.3% of the EPA limit 10000 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 9252 µg/L — TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 8/9 | SYR4 |
| Nitrate | 140 µg/L 1.4% of the EPA limit 10000 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 9230 µg/L — TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 8/9 | SYR4 |
| Copper | 166.05 µg/L 13% of the EPA limit 1300 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 212.5 µg/L — FRANKLIN SQUARE WD · 20,000 people · 2019 | 8/9 | SYR4 |
| Fluoride | 140 µg/L 3.5% of the EPA limit 4000 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 160 µg/L — LIBERTY UTILITIES NEW YORK - MERRICK · 135,000 people · 2019 | 4/9 | SYR4 |
| Nitrite | 147 µg/L 15% of the EPA limit 1000 µg/L Highest in the city: WA OF WESTERN NASSAU · 120,000 people · 2019 | 1/9 | SYR4 |
| Lithium | 14.9 µg/L No EPA limit set Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2025
Highest in the city: 139 µg/L — LIBERTY UTILITIES NEW YORK - MERRICK · 135,000 people · 2025 | 2/9 | UCMR-5 |
| Barium | 26 µg/L 1.3% of the EPA limit 2000 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 62.05 µg/L — WA OF WESTERN NASSAU · 120,000 people · 2019 | 8/9 | SYR4 |
| TTHM | 9.18 µg/L 11% of the EPA limit 80 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 23.59 µg/L — FRANKLIN SQUARE WD · 20,000 people · 2019 | 6/9 | SYR4 |
| cis-1,2-Dichloroethylene | 0.9350 µg/L 1.3% of the EPA limit 70 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 23.41 µg/L — WA OF WESTERN NASSAU · 120,000 people · 2019 | 4/9 | SYR4 |
| 1,1,1-Trichloroethane | 19.32 µg/L 9.7% of the EPA limit 200 µg/L Highest in the city: TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 4/9 | SYR4 |
| Trichloroethylene | 1.21 µg/L 24% of the EPA limit 5 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 19 µg/L — FRANKLIN SQUARE WD · 20,000 people · 2019 | 6/9 | SYR4 |
| Carbon Tetrachloride | 17.497 µg/L 350% of the EPA limit, at the 95th percentile of samples — 5 µg/L Highest in the city: TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 3/9 | SYR4 |
| 1,1-Dichloroethylene | 16.99 µg/L 243% of the EPA limit, at the 95th percentile of samples — 7 µg/L Highest in the city: TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 4/9 | SYR4 |
| Tetrachloroethylene | 9.41 µg/L 188% of the EPA limit, at the 95th percentile of samples — 5 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 16.94 µg/L — WA OF WESTERN NASSAU · 120,000 people · 2019 | 6/9 | SYR4 |
| Benzene | 12.538 µg/L 251% of the EPA limit, at the 95th percentile of samples — 5 µg/L Highest in the city: TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 2/9 | SYR4 |
| Toluene | 11.3 µg/L 1.1% of the EPA limit 1000 µg/L Highest in the city: WA OF WESTERN NASSAU · 120,000 people · 2019 | 4/9 | SYR4 |
| Cyanide | 11.2 µg/L 5.6% of the EPA limit 200 µg/L Highest in the city: LIBERTY UTILITIES NEW YORK - MERRICK · 135,000 people · 2019 | 1/9 | SYR4 |
| Chromium | 10 µg/L 10% of the EPA limit 100 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019 | 2/9 | SYR4 |
| Chloroform | 2.476 µg/L No EPA limit set Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 9.28 µg/L — TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 6/9 | SYR4 |
| Lead | 7.49 µg/L 50% of the EPA limit 15 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 9.14 µg/L — LIBERTY UTILITIES NEW YORK - MERRICK · 135,000 people · 2019 | 8/9 | SYR4 |
| Dibromochloromethane | 3.1 µg/L No EPA limit set Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 8.23 µg/L — FRANKLIN SQUARE WD · 20,000 people · 2019 | 7/9 | SYR4 |
| Gross Alpha, Excl. Radon And U | 4.9555 pCi/L 33% of the EPA limit 15 pCi/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 7.7175 pCi/L — LIBERTY UTILITIES NEW YORK - MERRICK · 135,000 people · 2019 | 6/9 | SYR4 |
| Combined Uranium | 5.018 µg/L 17% of the EPA limit 30 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 7.06016 µg/L — WA OF WESTERN NASSAU · 120,000 people · 2019 | 8/9 | SYR4 |
| 1,1,2-Trichloroethane | 6.77 µg/L 135% of the EPA limit, at the 95th percentile of samples — 5 µg/L Highest in the city: TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 2/9 | SYR4 |
| Bromoform | 2.775 µg/L No EPA limit set Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 6.405 µg/L — FRANKLIN SQUARE WD · 20,000 people · 2019 | 5/9 | SYR4 |
| Bromodichloromethane | 2 µg/L No EPA limit set Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 5.8405 µg/L — FRANKLIN SQUARE WD · 20,000 people · 2019 | 7/9 | SYR4 |
| Gross Beta Particle Activity | 4.865 pCi/L No EPA limit set Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 5.658 pCi/L — WA OF WESTERN NASSAU · 120,000 people · 2019 | 8/9 | SYR4 |
| Combined Radium (-226 And -228) | 4.2725 pCi/L 85% of the EPA limit 5 pCi/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 4.67 pCi/L — WA OF WESTERN NASSAU · 120,000 people · 2019 | 8/9 | SYR4 |
| Arsenic | 2.055 µg/L 21% of the EPA limit 10 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 4.51 µg/L — TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 4/9 | SYR4 |
| Total Haloacetic Acids (HAA5) | 1.495 µg/L 2.5% of the EPA limit 60 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 3.835 µg/L — WA OF WESTERN NASSAU · 120,000 people · 2018 | 3/9 | SYR4 |
| Selenium | 3.64 µg/L 7.3% of the EPA limit 50 µg/L Highest in the city: TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 4/9 | SYR4 |
| Monochloroacetic Acid | 3.12 µg/L No EPA limit set Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019 | 2/9 | SYR4 |
| Trichloroacetic Acid | 1.6 µg/L No EPA limit set Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 2.98 µg/L — WA OF WESTERN NASSAU · 120,000 people · 2018 | 2/9 | SYR4 |
| Dibromoacetic Acid | 1.26 µg/L No EPA limit set Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 2.94 µg/L — WA OF WESTERN NASSAU · 120,000 people · 2018 | 2/9 | SYR4 |
| Thallium, Total | 1.8335 µg/L 92% of the EPA limit 2 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 2.88 µg/L — TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 5/9 | SYR4 |
| Beryllium, Total | 0.5000 µg/L 13% of the EPA limit 4 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 2.5 µg/L — LIDO-POINT LOOKOUT WD · 2,000 people · 2019 | 4/9 | SYR4 |
| Vinyl Chloride | 2.2 µg/L 110% of the EPA limit, at the 95th percentile of samples — 2 µg/L Highest in the city: HEMPSTEAD (V) · 56,000 people · 2019 | 3/9 | SYR4 |
| Cadmium | 2.16 µg/L 43% of the EPA limit 5 µg/L Highest in the city: LIBERTY UTILITIES NEW YORK - MERRICK · 135,000 people · 2019 | 3/9 | SYR4 |
| Mercury | 1.82 µg/L 91% of the EPA limit 2 µg/L Highest in the city: TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 2/9 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 1.7 µg/L 28% of the EPA limit 6 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019 | 3/9 | SYR4 |
| Dichloroacetic Acid | 1.67 µg/L No EPA limit set Highest in the city: TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2018 | 2/9 | SYR4 |
| Chlorobenzene | 1.4975 µg/L 1.5% of the EPA limit 100 µg/L Highest in the city: WA OF WESTERN NASSAU · 120,000 people · 2019 | 1/9 | SYR4 |
| Antimony, Total | 0.8100 µg/L 14% of the EPA limit 6 µg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019
Highest in the city: 1.45 µg/L — TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 2/9 | SYR4 |
| 1,2-Dichloroethane | 1.42 µg/L 28% of the EPA limit 5 µg/L Highest in the city: TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 2/9 | SYR4 |
| Monobromoacetic Acid | 1.38 µg/L No EPA limit set Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2019 | 1/9 | SYR4 |
| trans-1,2-Dichloroethylene | 1.2055 µg/L 1.2% of the EPA limit 100 µg/L Highest in the city: TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 1/9 | SYR4 |
| Styrene | 1.17 µg/L 1.2% of the EPA limit 100 µg/L Highest in the city: TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 1/9 | SYR4 |
| Ethylbenzene | 0.9765 µg/L 0.1% of the EPA limit 700 µg/L Highest in the city: TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 1/9 | SYR4 |
| 1,2-Dichloropropane | 0.8445 µg/L 17% of the EPA limit 5 µg/L Highest in the city: TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 1/9 | SYR4 |
| Dichloromethane | 0.7000 µg/L 14% of the EPA limit 5 µg/L Highest in the city: LIBERTY UTILITIES NEW YORK - MERRICK · 135,000 people · 2019 | 2/9 | SYR4 |
| P-Dichlorobenzene | 0.7000 µg/L 0.9% of the EPA limit 75 µg/L Highest in the city: WA OF WESTERN NASSAU · 120,000 people · 2019 | 1/9 | SYR4 |
| Endrin | 0.0630 µg/L 3.2% of the EPA limit 2 µg/L Highest in the city: WA OF WESTERN NASSAU · 120,000 people · 2019 | 1/9 | SYR4 |
| Heptachlor Epoxide | 0.0435 µg/L 22% of the EPA limit 0.2000 µg/L Highest in the city: WA OF WESTERN NASSAU · 120,000 people · 2019 | 1/9 | SYR4 |
| Ethylene Dibromide | 0.0400 µg/L 80% of the EPA limit 0.0500 µg/L Highest in the city: TOWN OF HEMPSTEAD WATER DEPARTMENT · 110,000 people · 2019 | 2/9 | SYR4 |
| PFOA | 0.0100 µg/L No EPA limit set Highest in the city: WA OF WESTERN NASSAU · 120,000 people · 2024 | 1/9 | UCMR-5 |
| Pfpea | 0.0095 µg/L No EPA limit set Highest in the city: WA OF WESTERN NASSAU · 120,000 people · 2024 | 2/9 | UCMR-5 |
| Pfhxa | 0.0074 µg/L No EPA limit set Highest in the city: WA OF WESTERN NASSAU · 120,000 people · 2024 | 1/9 | UCMR-5 |
| Pfba | 0.0071 µg/L No EPA limit set Highest in the city: WA OF WESTERN NASSAU · 120,000 people · 2024 | 1/9 | UCMR-5 |
| PFHXS | 0.0063 µg/L No EPA limit set Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2025 | 2/9 | UCMR-5 |
| PFOS | 0.0051 µg/L No EPA limit set Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2025
Highest in the city: 0.0061 µg/L — WA OF WESTERN NASSAU · 120,000 people · 2024 | 3/9 | UCMR-5 |
| Lead | 0.0042 mg/L 28% of the EPA limit 0.0150 mg/L Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2025 | 9/9 | LCR |
| PFNA | 0.0041 µg/L No EPA limit set Main supplier: LIBERTY UTILITIES NEW YORK - LYNBROOK · 220,000 people · 2025 | 1/9 | UCMR-5 |
| PFBS | 0.0036 µg/L No EPA limit set Highest in the city: WA OF WESTERN NASSAU · 120,000 people · 2024 | 1/9 | UCMR-5 |
| Pfhpa | 0.0034 µg/L No EPA limit set Highest in the city: WA OF WESTERN NASSAU · 120,000 people · 2024 | 1/9 | UCMR-5 |
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 Hempstead
| Supplier | Population served |
|---|---|
| LIBERTY UTILITIES NEW YORK - LYNBROOK | 220,000 |
| LIBERTY UTILITIES NEW YORK - MERRICK | 135,000 |
| WA OF WESTERN NASSAU | 120,000 |
| TOWN OF HEMPSTEAD WATER DEPARTMENT | 110,000 |
| HEMPSTEAD (V) | 56,000 |
| WEST HEMPSTEAD WD | 32,031 |
| FRANKLIN SQUARE WD | 20,000 |
| LIDO-POINT LOOKOUT WD | 2,000 |
| CATHEDRAL GARDENS WD | 1,500 |
Frequently asked questions about Hempstead tap water
Is Hempstead tap water safe to drink?
EPA testing detected 64 contaminants in the water serving 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 Hempstead?
9 public water suppliers report drinking-water monitoring for Hempstead, New York to the EPA. Each is listed above with its population served.
What contaminants are in Hempstead's water?
The contaminants EPA monitoring detected in Hempstead include Nitrate-Nitrite, Nitrate, Copper, Fluoride, Nitrite. 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.