Tap Water Quality Report
Tap water quality in MAMARONECK, New York
Tap water in MAMARONECK, New York receives a grade of F (57/100) from TapWaterSafety.org. It's served by WESTCHESTER JOINT WATER WORKS. The most significant water quality concerns are: PFAS contamination; Haloacetic acids (HAA9) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline; Trichloroacetic acid significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in MAMARONECK's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving MAMARONECK.
PFAS contamination
Severe concernPerfluorooctane sulfonate (PFOS) detected. PFAS are persistent chemicals linked to cancer and immune effects with no known safe exposure threshold.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 55.8 ppb, 929x above the EWG health guideline of 0.06 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 41.0 ppb, 410x above the EWG health guideline of 0.1 ppb.
Trichloroacetic acid significantly above health guideline
Moderate concernTrichloroacetic acid detected at 26.7 ppb, 267x above the EWG health guideline of 0.1 ppb.
Recommended filters for MAMARONECK
Filters matched to the specific contaminants in MAMARONECK's 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.
All contaminants detected in MAMARONECK's tap water
Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. 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 |
|---|---|---|---|---|---|---|---|---|
| Haloacetic acids (HAA9) Disinfection byproduct |
55.8 ppb | 0.06 | — | — | — | — | — | 929× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
41.0 ppb | 0.1 | 60.0 | 60 | — | — | — | 410× over |
| Trichloroacetic acid Disinfection byproduct |
26.7 ppb | 0.1 | — | — | — | — | — | 267× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
30.2 ppb | 0.15 | 80.0 | 100 | — | — | — | 202× over |
| Dichloroacetic acid Disinfection byproduct |
13.3 ppb | 0.2 | — | — | — | — | — | 66× over |
| Chloroform Disinfection byproduct |
26.1 ppb | 0.4 | — | — | — | — | — | 65× over |
| Bromochloroacetic acid Disinfection byproduct |
1.06 ppb | 0.02 | — | — | — | — | — | 53× over |
| Bromodichloromethane Disinfection byproduct |
2.84 ppb | 0.06 | — | — | — | — | — | 47× over |
| Chromium (hexavalent) Heavy metal |
0.0568 ppb | 0.02 | — | — | — | — | — | 2.8× over |
| Nitrate and nitrite Inorganic |
0.141 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 1.0× over |
| Nitrate Inorganic |
0.14 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | Below guideline |
| Perfluorooctane sulfonate (PFOS) PFAS |
0.105 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | Below guideline |
| Manganese Heavy metal |
23.4 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Dibromochloromethane Disinfection byproduct |
0.0231 ppb | 0.1 | — | — | — | — | — | Below guideline |
| Chlorate Disinfection byproduct |
6.42 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
17.1 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
0.183 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
0.0183 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.0211 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Chromium (total) Heavy metal |
0.174 ppb | — | 100.0 | — | — | — | — | Below guideline |
| Cyanide Inorganic |
3.89 ppb | — | 200.0 | 50 | 70 | 150 | — | Below guideline |
| Fluoride Inorganic |
0.597 ppm | — | 4.0 | 1.5 | 1.5 | — | — | 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, California OEHHA PHGs, EWG Tap Water Database.
Treatment plant contact info
For service issues, water quality concerns, or to request a Consumer Confidence Report from WESTCHESTER JOINT WATER WORKS.