Tap Water Quality Report
Tap water quality in NEW CANAAN, Connecticut
Tap water in NEW CANAAN, Connecticut receives a grade of F (55/100) from TapWaterSafety.org. It's served by AQUARION-EASTERN FAIRFIELD COUNTY. The most significant water quality concerns are: PFAS contamination; Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in NEW CANAAN's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving NEW CANAAN.
PFAS contamination
Severe concernPerfluorooctane sulfonate (PFOS), Perfluorooctanoic acid (PFOA) 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 58.1 ppb, 968x above the EWG health guideline of 0.06 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 52.4 ppb, 349x above the EWG health guideline of 0.15 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 31.9 ppb, 319x above the EWG health guideline of 0.1 ppb.
EPA compliance record
Official U.S. EPA records for AQUARION-EASTERN FAIRFIELD COUNTY (system ID CT0150011) for the last 3 years. Checked 2026-10-07.
| Rule | Type | Since | Status |
|---|---|---|---|
| Arsenic Rule | Missed testing or reporting | 01/01/2021 | Resolved |
| Inorganic Chemicals | Missed testing or reporting | 01/01/2021 | Resolved |
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 NEW CANAAN
Filters matched to the specific contaminants in NEW CANAAN'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 NEW CANAAN'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 |
58.1 ppb | 0.06 | — | — | — | — | — | 968× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
52.4 ppb | 0.15 | 80.0 | 100 | — | — | — | 349× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
31.9 ppb | 0.1 | 60.0 | 60 | — | — | — | 319× over |
| Trichloroacetic acid Disinfection byproduct |
18.0 ppb | 0.1 | — | — | — | — | — | 180× over |
| Bromodichloromethane Disinfection byproduct |
10.0 ppb | 0.06 | — | — | — | — | — | 167× over |
| Chloroform Disinfection byproduct |
37.1 ppb | 0.4 | — | — | — | — | — | 93× over |
| Dichloroacetic acid Disinfection byproduct |
12.6 ppb | 0.2 | — | — | — | — | — | 63× over |
| Perfluorooctanoic acid (PFOA) PFAS |
1.66 ppt | 0.09 | 4.0 | 100 | 100 | 0.007 | — | 18× over |
| Dibromochloromethane Disinfection byproduct |
1.68 ppb | 0.1 | — | — | — | — | — | 17× over |
| Dibromoacetic acid Disinfection byproduct |
0.331 ppb | 0.03 | — | — | — | — | — | 11× over |
| Nitrate Inorganic |
0.765 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 5.5× over |
| Nitrate and nitrite Inorganic |
0.525 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 3.7× over |
| Perfluorooctane sulfonate (PFOS) PFAS |
0.893 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | 3.0× over |
| Chromium (hexavalent) Heavy metal |
0.0506 ppb | 0.02 | — | — | — | — | — | 2.5× over |
| Chlorate Disinfection byproduct |
137.1 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
10.4 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
1.01 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
12.1 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Vanadium Other |
0.243 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.0621 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Perfluorobutanoic Acid (PFBA) PFAS |
1.47 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA) PFAS |
0.807 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA) PFAS |
0.75 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoroheptanoic acid (PFHPA) PFAS |
0.279 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
0.293 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.0588 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.324 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 AQUARION-EASTERN FAIRFIELD COUNTY.
General Contact
Treatment Plant
ZIP codes served
NEW CANAAN's public water systems serve the following ZIP codes: