Tap Water Quality Report
Tap water quality in CAMBRIDGE, Massachusetts
Tap water in CAMBRIDGE, Massachusetts receives a grade of F (59/100) from TapWaterSafety.org. It's served by CAMBRIDGE WATER DEPARTMENT. The most significant water quality concerns are: PFAS contamination; Perfluorohexane sulfonate (PFHXS) significantly above health guideline; Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in CAMBRIDGE's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving CAMBRIDGE.
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 1.96 ppt, 1960x above the EWG health guideline of 0.001 ppt.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 13.7 ppb, 228x above the EWG health guideline of 0.06 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 11.6 ppb, 77x above the EWG health guideline of 0.15 ppb.
EPA compliance record
Official U.S. EPA records for CAMBRIDGE WATER DEPARTMENT (system ID MA3049000) for the last 3 years. Checked 2026-10-07.
Source: U.S. EPA Enforcement and Compliance History Online (ECHO), from the Safe Drinking Water Information System. See EPA's full report.
Recommended filters for CAMBRIDGE
Filters matched to the specific contaminants in CAMBRIDGE's water supply.
Filter certified for PFOA/PFOS (NSF/ANSI 53 or 58)
$180-$750Reverse osmosis and some carbon block filters reduce PFAS. Look for certification to NSF/ANSI 53 or 58 for PFOA/PFOS.
Carbon filter certified for VOCs (NSF/ANSI 53)
$180-$599Activated carbon is effective for disinfection byproducts. Look for NSF/ANSI 53 VOC reduction.
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 CAMBRIDGE'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 |
|---|---|---|---|---|---|---|---|---|
| Perfluorooctanoic acid (PFOA) PFAS |
5.96 ppt | 0.09 | 4.0 | 100 | 100 | 0.007 | — | EPA violation |
| Perfluorohexane sulfonate (PFHXS) PFAS |
1.96 ppt | 0.001 | 10.0 | — | — | — | — | 1960× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
13.7 ppb | 0.06 | — | — | — | — | — | 228× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
11.6 ppb | 0.15 | 80.0 | 100 | — | — | — | 77× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
6.54 ppb | 0.1 | 60.0 | 60 | — | — | — | 65× over |
| Bromodichloromethane Disinfection byproduct |
3.41 ppb | 0.06 | — | — | — | — | — | 57× over |
| Dibromoacetic acid Disinfection byproduct |
1.3 ppb | 0.03 | — | — | — | — | — | 43× over |
| Dibromochloromethane Disinfection byproduct |
3.24 ppb | 0.1 | — | — | — | — | — | 32× over |
| Dichloroacetic acid Disinfection byproduct |
5.07 ppb | 0.2 | — | — | — | — | — | 25× over |
| Perfluorononanoic acid (PFNA) PFAS |
0.11 ppt | 0.006 | 10.0 | — | — | — | — | 18× over |
| Chloroform Disinfection byproduct |
4.0 ppb | 0.4 | — | — | — | — | — | 10× over |
| Perfluorooctane sulfonate (PFOS) PFAS |
2.18 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | 7.3× over |
| Radium, combined (-226 and -228) Radiological |
0.21 pCi/L | 0.05 | 5.0 | — | — | — | — | 4.1× over |
| Chromium (hexavalent) Heavy metal |
0.0563 ppb | 0.02 | — | — | — | — | — | 2.8× over |
| Nitrate Inorganic |
0.35 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 2.5× over |
| Bromoform Disinfection byproduct |
0.99 ppb | 0.5 | — | — | — | — | — | 2.0× over |
| Bromate Disinfection byproduct |
0.12 ppb | 0.1 | 10.0 | 10 | 10 | 0.1 | — | 1.2× over |
| Chlorate Disinfection byproduct |
231.3 ppb | 210.0 | — | — | — | — | — | 1.1× over |
| Trichloroacetic acid Disinfection byproduct |
0.105 ppb | 0.1 | — | — | — | — | — | 1.0× over |
| Aluminum Heavy metal |
31.8 ppb | 600.0 | — | 200 | — | 600 | — | Below guideline |
| Barium Heavy metal |
36.7 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Manganese Heavy metal |
3.56 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA) PFAS |
3.44 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoroheptanoic acid (PFHPA) PFAS |
2.08 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA) PFAS |
1.78 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
2.35 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
0.0542 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.00813 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.146 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Bromide Other |
71.9 ppb | — | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.7 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Nitrite Inorganic |
0.00326 ppm | — | 1.0 | — | — | — | — | 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 CAMBRIDGE WATER DEPARTMENT.