City water profile

Water hardness in Norwalk

Find official utility reports, understand hardness, and check the water system serving your home in Norwalk, Connecticut.

Utility-reported hardness

Not yet available

Check your provider and source →

State comparison: Unavailable
Evidence comparison rank: —
Matched utilities: 4
Active health records: 0

Your tap water

What does the utility report?

Match the utility name to your water bill. These results describe the utility’s water, not a test at your home. A ZIP can include several water systems.

Utility hardness unavailable in this index

Nearby river or groundwater samples cannot tell us the hardness coming out of your tap. Ask your water provider for total hardness as CaCO₃, or test it at home.

Find an official utility report →

Convert a hardness result →Test your tap →

Match the name on your water bill

Your utility’s measurements and compliance records

These are possible serving systems. A record for one system does not apply to every home in this ZIP. Confirm your provider before interpreting a measurement or notice. Federal records can lag current utility notices.

EPA snapshot: 2026Q2. Historical window begins Jan 1, 2021.

Aquarion-Eastern Fairfield County

CT0150011 · Surface water · 351,756 people served system-wide

The system names this served city; Census place overlap links the city to this ZCTA.

No active health-based record in this imported snapshot

Find this utility’s official report →

Measurements (1)

An action level is a regulatory trigger, not a pass/fail health boundary. A reported zero is the value in the source record and does not establish that lead is absent at your tap.

Lead (90th percentile)

EPA SDWIS Lead and Copper Rule samples

Below action level

Reported level: 0 mg/L
Action level: 0.015 mg/L

0% of the listed benchmark

Monitoring period: Jan 1, 2025 to Dec 31, 2025

Violation history (24)

Imported violation history for Aquarion-Eastern Fairfield County
Rule	Status	Period
Arsenic	Archived	Jan 1, 2021 to Dec 31, 2023
Barium	Archived	Jan 1, 2021 to Dec 31, 2023
Chromium	Archived	Jan 1, 2021 to Dec 31, 2023
CYANIDE	Archived	Jan 1, 2021 to Dec 31, 2023
Antimony, Total	Archived	Jan 1, 2021 to Dec 31, 2023
Beryllium, Total	Archived	Jan 1, 2021 to Dec 31, 2023
Selenium	Archived	Jan 1, 2021 to Dec 31, 2023
Arsenic	Archived	Jan 1, 2021 to Dec 31, 2023
Cadmium	Archived	Jan 1, 2021 to Dec 31, 2023
Barium	Archived	Jan 1, 2021 to Dec 31, 2023
Mercury	Archived	Jan 1, 2021 to Dec 31, 2023
Nickel	Archived	Jan 1, 2021 to Dec 31, 2023
Antimony, Total	Archived	Jan 1, 2021 to Dec 31, 2023
Nickel	Archived	Jan 1, 2021 to Dec 31, 2023
Cadmium	Archived	Jan 1, 2021 to Dec 31, 2023
Thallium, Total	Archived	Jan 1, 2021 to Dec 31, 2023
Mercury	Archived	Jan 1, 2021 to Dec 31, 2023
Beryllium, Total	Archived	Jan 1, 2021 to Dec 31, 2023
Chromium	Archived	Jan 1, 2021 to Dec 31, 2023
Thallium, Total	Archived	Jan 1, 2021 to Dec 31, 2023
Fluoride	Archived	Jan 1, 2021 to Dec 31, 2023
CYANIDE	Archived	Jan 1, 2021 to Dec 31, 2023
Selenium	Archived	Jan 1, 2021 to Dec 31, 2023
Fluoride	Archived	Jan 1, 2021 to Dec 31, 2023

South Norwalk Electric & Water

CT1030021 · Surface water · 42,000 people served system-wide

The system names this served city; Census place overlap links the city to this ZCTA.

No active health-based record in this imported snapshot

Find this utility’s official report →

Measurements (1)

An action level is a regulatory trigger, not a pass/fail health boundary. A reported zero is the value in the source record and does not establish that lead is absent at your tap.

Lead (90th percentile)

EPA SDWIS Lead and Copper Rule samples

Below action level

Reported level: 0.002 mg/L
Action level: 0.015 mg/L

13% of the listed benchmark

Monitoring period: Jan 1, 2023 to Dec 31, 2025

Violation history (2)

Imported violation history for South Norwalk Electric & Water
Rule	Status	Period
Consumer Confidence Rule	Resolved	Aug 10, 2024 to Aug 13, 2024
Consumer Confidence Rule	Resolved	Jul 1, 2024 to Aug 12, 2024

Norwalk First Taxing District

CT1030011 · Surface water · 40,256 people served system-wide

The system names this served city; Census place overlap links the city to this ZCTA.

No active health-based record in this imported snapshot

Find this utility’s official report →

Measurements (1)

An action level is a regulatory trigger, not a pass/fail health boundary. A reported zero is the value in the source record and does not establish that lead is absent at your tap.

Lead (90th percentile)

EPA SDWIS Lead and Copper Rule samples

Below action level

Reported level: 0.003 mg/L
Action level: 0.015 mg/L

20% of the listed benchmark

Monitoring period: Jan 1, 2025 to Dec 31, 2025

Violation history (1)

Imported violation history for Norwalk First Taxing District
Rule	Status	Period
Lead and Copper Rule	Resolved	Dec 30, 2021 to Aug 23, 2021

Aquarion-Darien

CT0350011 · Surface water · 18,737 people served system-wide

The system names this served city; Census place overlap links the city to this ZCTA.

No active health-based record in this imported snapshot

Find this utility’s official report →

Measurements (1)

An action level is a regulatory trigger, not a pass/fail health boundary. A reported zero is the value in the source record and does not establish that lead is absent at your tap.

Lead (90th percentile)

EPA SDWIS Lead and Copper Rule samples

Below action level

Reported level: 0.002 mg/L
Action level: 0.015 mg/L

13% of the listed benchmark

Monitoring period: Jan 1, 2021 to Dec 31, 2023

Violation history (0)

No record returned in this imported window. This is not a guarantee of tap-water safety.

City summary

What the indexed records say

Norwalk has 5 published ZIP profiles across Fairfield County. The regional-evidence median is 114 PPM. The city does not meet the stricter comparison standard.

The 102.1–119 PPM range shows how much the available ZIP estimates vary within the city label.

Hardness distribution

How local ZIP estimates compare

Soft0 ZIPs

Moderately hard5 ZIPs

Hard0 ZIPs

Very hard0 ZIPs

5 of 5 ZIP profiles have a hardness estimate. Bars count ZIP profiles, not households or laboratory samples.

Evidence quality

Distance, dates, and confidence

Median nearest distance: 3.1 miles
Profiles with evidence: 5/5

Confidence labels

High: 5Moderate: 0Low: 0

1. Open your ZIP. Check distance, dates, confidence, and the associated utility.
2. Read the current CCR. Confirm source water, detections, limits, ranges, and notices.
3. Use a measured hardness result. Confirm health concerns or treatment sizing with the right method.

Continue comparing

Other Connecticut communities

Bethel

Fairfield County

95 PPM median

Bridgeport

Fairfield County

89 PPM median

Danbury

Fairfield County

95 PPM median

Greenwich

Fairfield County

119 PPM median

New Canaan

Fairfield County

114 PPM median

Newtown

Fairfield County

92 PPM median

Search all 52 Connecticut cities →

Questions people ask

About water in Norwalk

Is the water hard?

Check the utility-reported result above when available. Nearby environmental samples cannot establish tap-water hardness. Ask your provider or test your tap.

Is the tap water safe?

Compliance history is utility-wide and cannot guarantee conditions at every tap. Check current notices and test when address-specific evidence is needed.

Do I need treatment?

Choose treatment only after confirming the problem at the property. A softener targets hardness; contaminant treatment requires a matching, verified performance claim.