Water Quality Report · Updated May 12, 2026
WA OF WESTERN NASSAU
WA OF WESTERN NASSAU delivers tap water graded F (49/100) by TapWaterSafety.org. The utility serves approximately 120,000 residents in HEMPSTEAD (T), New York using groundwater. The most significant water quality concerns are: PFAS contamination; Perfluorohexane sulfonate (PFHXS) significantly above health guideline; Haloacetic acids (HAA9) significantly above health guideline. For questions, the utility can be reached at 516-327-4053.
Is HEMPSTEAD (T) tap water safe to drink?
WA OF WESTERN NASSAU delivers tap water that earns a grade of F (49/100) from TapWaterSafety.org — a poor rating, with significant contamination concerns and/or recent violations.
The utility serves 120,000 residents in HEMPSTEAD (T) and 1 other community, drawing from groundwater.
Public testing data identifies 14 contaminants in this water above EWG's health-based guidelines, including: Perfluorohexane sulfonate (PFHXS), Haloacetic acids (HAA9), Perfluorononanoic acid (PFNA), Radium, combined (-226 and -228), Nitrate, Nitrate and nitrite, Perfluorooctanoic acid (PFOA), Chromium (hexavalent), Uranium, Perfluorooctane sulfonate (PFOS), 1,4-Dioxane, Chlorate, Dibromoacetic acid, Total trihalomethanes (TTHMs). For most residents, a properly certified home filter at the kitchen tap is the most cost-effective way to reduce exposure to whatever's in your water. See our filter recommendations below, matched specifically to this utility's contaminant profile.
Quick actions for HEMPSTEAD (T) residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for WA OF WESTERN NASSAU.
PFAS contamination
Severe concernPerfluorononanoic acid (PFNA), Perfluorooctane sulfonate (PFOS) detected. PFAS are persistent chemicals linked to cancer and immune effects with no known safe exposure threshold.
Perfluorohexane sulfonate (PFHXS) significantly above health guideline
Moderate concernPerfluorohexane sulfonate (PFHXS) detected at 0.805 ppt, 805x above the EWG health guideline of 0.001 ppt.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 2.44 ppb, 41x above the EWG health guideline of 0.06 ppb.
Contact WA OF WESTERN NASSAU
Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.
General Contact
Treatment Plant
Recommended water filters for HEMPSTEAD (T)
Filters matched to the specific contaminants in this water supply.
Reverse Osmosis or NSF P473 certified carbon
$80-$750Activated carbon and RO are the only technologies proven to remove PFAS at certified levels.
Carbon block (NSF/ANSI 42 + 53)
$40-$750Activated carbon is highly effective for disinfection byproducts like TTHM and HAA5.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
Score breakdown
This utility's overall score of 49/100 breaks down across five weighted components. Read the full methodology →
Contaminants detected — international standards comparison
Every contaminant detected, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal (the strictest US benchmark). Why we show multiple standards →
| Contaminant | Detected | EWG US health-based |
EPA US legal |
EU DWD Europe |
WHO global |
CA PHG strictest US |
Tested sample year |
Status |
|---|---|---|---|---|---|---|---|---|
| Perfluorohexane sulfonate (PFHXS) PFAS |
0.805 ppt | 0.001 | 10.0 | — | — | — | — | 805× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
2.44 ppb | 0.06 | — | — | — | — | — | 41× over |
| Perfluorononanoic acid (PFNA) PFAS |
0.213 ppt | 0.006 | 10.0 | — | — | — | — | 36× over |
| Radium, combined (-226 and -228) Radiological |
1.72 pCi/L | 0.05 | 5.0 | — | — | — | — | 34× over |
| Nitrate Inorganic |
3.56 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 25× over |
| Nitrate and nitrite Inorganic |
3.57 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 25× over |
| Perfluorooctanoic acid (PFOA) PFAS |
2.23 ppt | 0.09 | 4.0 | 100 | 100 | 0.007 | — | 25× over |
| Chromium (hexavalent) Heavy metal |
0.248 ppb | 0.02 | — | — | — | — | — | 12× over |
| Uranium Radiological |
1.71 pCi/L | 0.43 | 20.0 | 30 | 30 | 0.43 | — | 4.0× over |
| Perfluorooctane sulfonate (PFOS) PFAS |
0.954 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | 3.2× over |
| 1,4-Dioxane Semi-volatile organic compound |
1.09 ppb | 0.35 | — | — | 50 | 1 | — | 3.1× over |
| Chlorate Disinfection byproduct |
356.8 ppb | 210.0 | — | — | — | — | — | 1.7× over |
| Dibromoacetic acid Disinfection byproduct |
0.0387 ppb | 0.03 | — | — | — | — | — | 1.3× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
0.187 ppb | 0.15 | 80.0 | 100 | — | — | — | 1.2× over |
| Dibromochloromethane Disinfection byproduct |
0.0915 ppb | 0.1 | — | — | — | — | — | Below guideline |
| Haloacetic acids (HAA5) Disinfection byproduct |
0.0522 ppb | 0.1 | 60.0 | 60 | — | — | — | Below guideline |
| Perchlorate Disinfection byproduct |
0.343 ppb | 1.0 | — | — | — | — | — | Below guideline |
| Bromodichloromethane Disinfection byproduct |
0.0199 ppb | 0.06 | — | — | — | — | — | Below guideline |
| Benzo[a]pyrene Other |
0.00111 ppb | 0.007 | 0.2 | — | — | — | — | Below guideline |
| Bromoform Disinfection byproduct |
0.0582 ppb | 0.5 | — | — | — | — | — | Below guideline |
| Tetrachloroethylene (perchloroethylene) Volatile organic compound |
0.00485 ppb | 0.06 | 5.0 | — | — | — | — | Below guideline |
| Chloroform Disinfection byproduct |
0.0248 ppb | 0.4 | — | — | — | — | — | Below guideline |
| 6:2 Fluorotelomer sulfonate (6 2FTS) Other |
0.045 ppt | 1.0 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
2.73 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Barium Heavy metal |
16.5 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Perfluorobutanoic Acid (PFBA) PFAS |
3.33 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA) PFAS |
3.06 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA) PFAS |
2.14 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
0.0316 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Perfluoroheptanoic acid (PFHPA) PFAS |
0.656 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.0119 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
0.35 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Picloram Other |
0.0161 ppb | 166.0 | 500.0 | — | — | — | — | Below guideline |
| Strontium Radiological |
0.0854 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| 1,1-Dichloroethane Volatile organic compound |
7.5e-05 ppb | 3.0 | — | — | — | — | — | Below guideline |
| Xylenes (total) Volatile organic compound |
0.000976 ppb | 1800.0 | 10000.0 | — | — | — | — | Below guideline |
| Acetic acid Other |
2.22 ppb | — | — | 60 | — | — | — | Below guideline |
| Acetone Other |
0.879 ppb | — | — | — | — | — | — | Below guideline |
| Chlorodifluoromethane Other |
0.035 ppb | — | — | — | — | — | — | Below guideline |
| Dinoseb Pesticide/Herbicide |
0.0811 ppb | — | 7.0 | — | — | — | — | Below guideline |
| Formaldehyde Other |
1.5 ppb | — | — | — | — | — | — | Below guideline |
All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.
Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines (4th ed.), California OEHHA PHGs, EWG Tap Water Database.
WA OF WESTERN NASSAU service area
This water system serves 2 communities in Nassau County, New York. Click any city for its dedicated tap water quality page.
Find the right filter for HEMPSTEAD (T) water
Browse filter categories by water-quality concern. Each option below is NSF-certified for the matched contaminant type.