Drinking water quality · 2024
· Verified
What's in Stamford, CT tap water
21 contaminants were measured in the Stamford, CT water system's 2024 annual report. Each is shown below against its federal limit — 1 sit at or above that limit.
- Reporting year
- 2024
- Contaminants measured
- 21
- Over federal limit
- 1
- Approaching the limit
- 1
- Worst contaminant
- pH
- Service area
- CT
PFAS — EPA UCMR5 (2023–2025)
2 PFAS compounds above EPA limits in Stamford, CT
The EPA finalized the first-ever federal drinking-water limits for six PFAS compounds in April 2024. These numbers come straight from EPA's UCMR5 lab dataset — every U.S. system serving more than 3,300 people tested every PFAS sample at an entry point to its distribution system. PFAS not listed below were either tested and not detected, or not yet sampled.
PFOA (Perfluorooctanoic acid)
● Over EPA limit (2.7×)near national p90 (13.649999999999999 ng/L across detecting U.S. systems)
PFOS (Perfluorooctane sulfonic acid)
● Over EPA limit (1.6×)below national p90 (19.900000000000006 ng/L across detecting U.S. systems)
PFPeA
● Detected (no federal limit)below national p90 (15.95999999999999 ng/L across detecting U.S. systems)
PFBA
● Detected (no federal limit)below national p90 (18 ng/L across detecting U.S. systems)
PFHpA
● Detected (no federal limit)below national p90 (9.309999999999999 ng/L across detecting U.S. systems)
PFBS
● Detected (no federal limit)below national p90 (13.909999999999979 ng/L across detecting U.S. systems)
PFHxA
● Detected (no federal limit)near national p90 (12.190000000000003 ng/L across detecting U.S. systems)
Where your water comes from · EPA SDWIS
Stamford, CT's drinking water comes from surface water, drawn from 17 sources.
Source
- WESTPORT · 4
- COLEYTOWN · 2
- ASPETUCK RESERVOIR
- EASTON LAKE RESERVOIR INTAKE
- + 9 more
Treatment
- COLEYTOWN WELLFIELD TREATMENT PLANT
- EASTON WATER TREATMENT PLANT
- HEMLOCKS WATER TREATMENT PLANT
- + 3 more
Distribution
Also buys water from NORWALK FIRST TAXING DISTRICT, AQUARION-STAMFORD, and 1 more.
Historical readings · EPA Six-Year Review (2012–2019)
2 contaminants historically over EPA limits in Stamford, CT
Every U.S. public water system reports compliance-monitoring data to EPA. The Six-Year Review releases the 2012–2019 window as a single dataset — here's what your system reported, year by year. Values shown are the highest detection per analyte per year, compared to the federal MCL.
| Contaminant | Worst detection | EPA limit | Years (2012–2019) |
|---|---|---|---|
TTHM worst: 2018 | 0.101 mg/L 1.3× | 0.08 mg/L | '12'13'14'15'16'17'18'19 |
HAA5 worst: 2014 | 0.075 mg/L 1.3× | 0.06 mg/L | '12'13'14'15'16'17'18'19 |
FLUORIDE worst: 2014 | 1.08 mg/L within | 4 mg/L | '12'13'14'15'16'17'18'19 |
NITRATE worst: 2014 | 1.56 mg/L within | 10 mg/L | '12'13'14'15'16'17'18'19 |
NITRATE NITRITE worst: 2014 | 1.56 mg/L within | 10 mg/L | '12'13'14'15'16'17'18'19 |
BARIUM worst: 2017 | 0.055 mg/L within below national p90 | 2 mg/L | '12'13'14'15'16'17'18'19 |
COPPER worst: 2012 | 0.36 mg/L below national p90 | — | '12'13'14'15'17'18 |
LEAD worst: 2012 | 0.668 mg/L | — | '12'15'18 |
DBAA worst: 2012 | 0.001 mg/L | — | '12'13'14'15'16'17'18'19 |
DCAA worst: 2012 | 0.027 mg/L | — | '12'13'14'15'16'17'18'19 |
MBAA worst: 2015 | 0.001 mg/L | — | '15'16'19 |
MCAA worst: 2012 | 0.002 mg/L | — | '12'13'14'15'16'17'18'19 |
TCAA worst: 2012 | 0.032 mg/L | — | '12'13'14'15'16'17'18'19 |
BROMODICHLOROMETHANE worst: 2012 | 0.015 mg/L | — | '12'13'14'15'16'17'18'19 |
BROMOFORM worst: 2015 | 0.0005 mg/L | — | '15'17 |
CHLOROFORM worst: 2012 | 0.055 mg/L | — | '12'13'14'15'16'17'18'19 |
DIBROMOCHLOROMETHANE worst: 2012 | 0.003 mg/L | — | '12'13'14'15'16'17'18'19 |
Physical & aggregate
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| pHA measure of how acidic or basic the water is. | 7.4AverageSystem-wide | 6.4MCL | At or above the limit |
| ColorA measure of visible tint in the water. | 2AverageSystem-wide | 15MCL | Within the limit |
| TurbidityA measure of cloudiness from suspended particles in the water. | 0.14 NTUAverageSystem-wide | 5 NTUMCL | Within the limit |
| HardnessA measure of dissolved calcium and magnesium minerals. | 2024Reported levelTest Date | None set | Detected — no federal limit |
| TOCTotal organic carbon — a measure of organic material dissolved in the water. | 1.6AverageSystem-wide | None set | Detected — no federal limit |
Metals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| SodiumA naturally occurring salt component. | 33 mg/LAverageSystem-wide | 100 mg/LNL | Within the limit |
Disinfectants
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ChlorineA disinfectant added to drinking water to kill bacteria and viruses. | 0.87 mg/LAverageSystem-wide | 4 mg/LMRDLG | Within the limit |
Inorganic chemicals
PFAS ("forever chemicals")
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Perfluorohexanesulfonic acidPerfluorohexanesulfonic acid, a PFAS 'forever chemical.' | Not detected ng/LAverageSystem-wide | 49 ng/LAction level | Within the limit |
Microbial
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Total ColiformA group of bacteria used as an indicator of overall water-system sanitation. | 0AverageSystem-wide | 0MCLG | Detected — no federal limit |
People also ask about Stamford, CT's water
+Is Stamford, CT tap water safe to drink in 2024?
The 2024 Consumer Confidence Report for the Stamford, CT water utility lists 1 contaminant at or above the federal limit: pH. Whether that means the water is "unsafe" depends on which contaminant, how long the exposure, and individual health factors. The table on this page shows the measured value, the federal threshold, and the regulated statistic used for compliance.
+What contaminants are in Stamford, CT tap water?
21 contaminants were measured in Stamford, CT's 2024 Consumer Confidence Report, spanning physical & aggregate, inorganic chemicals, and metals. 19 have an enforceable federal limit; the rest are detected but unregulated. Every measured value, in the utility's own units, is on this page.
+Which contaminants exceed federal limits in Stamford, CT tap water?
One contaminant in Stamford, CT's 2024 report sits at or above the federal limit: pH (1.2× the limit). The EPA enforces these limits against the regulated reporting statistic — typically a running annual average or 90th percentile — not a one-off sample spike.
+What is the worst contaminant in Stamford, CT tap water?
The contaminant with the highest measured value relative to its federal limit in the 2024 report is pH, at 1.2× the federal threshold. It belongs to the physical & aggregate family of contaminants.
+Are any contaminants in Stamford, CT tap water approaching the federal limit?
One contaminant is between 80% and 100% of the federal limit in this report: HAA5. Approaching means measured but not in violation — a margin that can close quickly if conditions change.
+Where does the data on this page come from?
Every value is transcribed from Stamford, CT's 2024 Consumer Confidence Report — the annual drinking-water report every U.S. public water utility is required by federal law to publish. The original source document is archived and viewable on this site. A water-quality report covers an entire service area, not a single address.
+How often is Stamford, CT's water quality data updated?
Each U.S. public water utility publishes one Consumer Confidence Report per year, covering the prior calendar year's measurements. This page reflects the 2024 report; a new report will replace it once the utility publishes its next annual update.