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City water profile

Water hardness in Stonington

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

Utility-reported hardness

Not yet available

Check your provider and source →
State comparison
Unavailable
Evidence comparison rank
—
Matched utilities
3
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-Mystic

CT1370011 · Surface water · 10,788 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 (0)

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

Ctwc - Shoreline Region-Masons Island

CT1370051 · Surface water · 445 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 (1)
Imported violation history for Ctwc - Shoreline Region-Masons Island
RuleStatusPeriod
Lead and Copper RuleResolvedDec 30, 2021 to Jan 10, 2022

Aquarion-Arlington Acres

CT1370071 · Groundwater · 392 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 (2)

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
0.0019 mg/L
Action level
0.015 mg/L

13% of the listed benchmark

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

Copper (90th percentile)

EPA SDWIS Lead and Copper Rule samples

Above action level
Reported level
1.61 mg/L
Action level
1.3 mg/L

124% of the listed benchmark

Monitoring period: Dec 31, 1997 to Jun 30, 1998

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

Stonington has 1 published ZIP profile across New London County. The regional-evidence median is 16 PPM. The city does not meet the stricter comparison standard.

Because only one ZIP is represented, the city median and range are the same local estimate. It should not be read as multiple independent samples across the community.

Hardness distribution

How local ZIP estimates compare

Soft1 ZIP
Moderately hard0 ZIPs
Hard0 ZIPs
Very hard0 ZIPs

1 of 1 ZIP profiles have a hardness estimate. Bars count ZIP profiles, not households or laboratory samples.

Evidence quality

Distance, dates, and confidence

Median nearest distance
3.9 miles
Profiles with evidence
1/1

Confidence labels

High: 1Moderate: 0Low: 0

Observation window: Aug 3, 2016 to May 26, 2026.

ZIP directory

Water reports in Stonington

Open a ZIP for site-level provenance and measurements.

ZIP code

06378

Soft

15.8 PPM

Nearest site
3.9 mi
Confidence
High

View full ZIP evidence →

Practical next steps

Move from index to evidence

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

Questions people ask

About water in Stonington

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.