Tap Water Results

Is Norwalk, CT tap water safe?

Data: U.S. EPA · How we read the data · How we check it

Summary

No federal limits exceeded in EPA data for Aquarion-Eastern Fairfield County. 7 PFAS were detected below the limits.

4 public water systems serve parts of Norwalk. The largest, Aquarion-Eastern Fairfield County, serves 351,756 people, and one system here had PFAS above a federal limit. Your water bill names your system.

Largest system

Aquarion-Eastern Fairfield County

351,756 people · Surface water · EPA ID CT0150011

Buys treated water from Aquarion-Stamford, Aquarion-Ridgefield, Norwalk First Taxing District.

PFASHighest averageLimitStatus
PFOA
One sample above limit
1.05 ppt4 pptOne sample above limit
PFOS
One sample above limit
0 ppt4 pptOne sample above limit
PFHxS
Not detected
–10 pptNot detected
PFNA
Not detected
–10 pptNot detected
HFPO-DA (GenX)
Not detected
–10 pptNot detected

ppt = parts per trillion. "Highest average" is the highest average at any of the system's entry points, the way EPA compares results with the limits.

Lead: 0 ppb at the 90th percentile (Nov 2026, and 9 in 10 homes sampled were at or below it) Below action level
Health-based violations since 2016: 0

Full Aquarion-Eastern Fairfield County results

Across Connecticut, 29 of 62 water systems EPA tested had PFAS above a 2024 federal limit, and 1 system were above the lead action level in results from the last five years. Connecticut results.

Norwalk homes and lead pipes

69%
of homes built before 1980 (Connecticut 67%, US 50%)
25%
built before 1950 (Connecticut 27%)
44%
of households rent (Connecticut 34%)

Lead service lines and lead solder were allowed until 1986, so homes from before then are the ones to check. Renting? Ask your landlord what the service line is made of, because it's their pipe to replace. How to check your own line.

Housing: Census American Community Survey 2020–2024 5-year estimates for Norwalk city (tables B25034, B25003). Estimates for small places have a margin of error.

Which system serves your ZIP code

Based on the ZIP codes each system reported serving. Boundaries don't follow ZIP lines exactly, so your water bill is the final word.

SystemZIP codes in Norwalk
South Norwalk Electric & Water
42,000 people
06850, 06853, 06854, 06855
Norwalk First Taxing District
40,256 people
06851

Other water systems serving Norwalk

How nearby cities compare

CityMain water systemPFASLead (90th pct.)
Stamford 7 mi
Aquarion-Eastern Fairfield County
Aquarion-Eastern Fairfield CountyNone above limits0 ppb
Bridgeport 13 mi
Aquarion-Eastern Fairfield County
Aquarion-Eastern Fairfield CountyNone above limits0 ppb
Milford 21 mi
Regional Water Authority
Regional Water AuthorityAbove limit0 ppb
Shelton 21 mi
Aquarion-Eastern Fairfield County
Aquarion-Eastern Fairfield CountyNone above limits0 ppb
Danbury 21 mi
Danbury Water Department
Danbury Water DepartmentAbove limit0 ppb
West Haven 27 mi
Regional Water Authority
Regional Water AuthorityAbove limit0 ppb

Questions

Is Norwalk tap water safe to drink?

Aquarion-Eastern Fairfield County has had no health-based violations since 2016. Utility data can't show lead from your own pipes: if your home was built before 1986, test your tap. Your utility's annual Consumer Confidence Report is the official summary.

Who supplies water in Norwalk, CT?

4 public water systems serve parts of Norwalk. The largest is Aquarion-Eastern Fairfield County (351,756 people). Your water bill names your system. The EPA ID is also on your utility's Consumer Confidence Report.

Does Norwalk tap water have PFAS?

Aquarion-Eastern Fairfield County had 7 PFAS detected at least once in EPA's 2023–2025 testing, all with averages below the federal limits.

Do Norwalk homes have lead pipes?

Census estimates put 69% of Norwalk homes as built before 1980 (Connecticut: 67%). Lead service lines and lead solder were allowed until 1986, so older homes are more likely to have them. Aquarion-Eastern Fairfield County's service line inventory says what your line is made of. The only way to know for your home is to check the line where it enters the house and test your tap.

Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.