Utility-reported hardness
Unavailable
Ask your provider or test your tap
Local water dashboard
Official source aggregationWater quality in Colchester, CT 06415
Regional hardness evidence, possible serving systems, EPA compliance history, and the measurements that are—and are not—available for New London County.
2 active health-based record(s) across possible systems
- Largest possible serving system
- Colchester Sewer & Water Commission
- Source water
- Groundwater
- County
- New London County
- Profile updated
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 →At a glance
What the current records say
EPA quarter 2026Q2
All possible systems
Review needed
2 active health-based records
Measurements by utility
Each result belongs to a specific system.
Utility match
8 systems
Serves 4,020 people system-wide
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.
Colchester Sewer & Water Commission
CT0280011 · Groundwater · 4,020 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
- 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 (13)
| Rule | Status | Period |
|---|---|---|
| E. COLI | Archived | Mar 1, 2026 to Mar 31, 2026 |
| Consumer Confidence Rule | Resolved | Aug 10, 2025 to Aug 29, 2025 |
| Consumer Confidence Rule | Resolved | Jul 1, 2025 to Jul 25, 2025 |
| Public Notice | Resolved | Jun 15, 2025 to Aug 29, 2025 |
| Public Notice | Resolved | Jun 15, 2025 to Aug 29, 2025 |
| Public Notice | Resolved | May 25, 2024 to Aug 29, 2025 |
| E. COLI | Resolved | Mar 1, 2024 to Mar 31, 2024 |
| E. COLI | Resolved | Jan 1, 2024 to Jan 31, 2024 |
| Total Haloacetic Acids (HAA5) | Resolved | Jan 1, 2024 to Dec 31, 2024 |
| TTHM | Resolved | Jan 1, 2024 to Dec 31, 2024 |
| Consumer Confidence Rule | Resolved | Jul 1, 2023 to Jul 17, 2023 |
| Chlorine | Resolved | Oct 1, 2022 to Nov 30, 2022 |
| Consumer Confidence Rule | Resolved | Jul 1, 2021 to Jul 2, 2021 |
Ctwc - Amston Lake Division
CT0670331 · Groundwater · 910 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
- Reported level
- 0.0015 mg/L
- Action level
- 0.015 mg/L
10% 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.
Colchester Estates
CT0280041 · Groundwater · 276 people served system-wide
The system names this served city; Census place overlap links the city to this ZCTA.
1 reported active health-based record(s) for this system
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
- 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 (32)
| Rule | Status | Period |
|---|---|---|
| Lead and Copper Rule | Resolved | Dec 30, 2024 to Dec 31, 2024 |
| LEAD AND COPPER RULE REVISIONSHealth-based | Unaddressed | Oct 17, 2024 |
| LEAD AND COPPER RULE REVISIONS | Unaddressed | Oct 17, 2024 |
| Nitrate | Resolved | Jan 1, 2023 to Dec 31, 2023 |
| Nitrite | Resolved | Jan 1, 2023 to Dec 31, 2023 |
| Consumer Confidence Rule | Resolved | Aug 10, 2022 to Oct 12, 2022 |
| Public Notice | Resolved | Dec 29, 2021 to Mar 11, 2022 |
| Consumer Confidence Rule | Resolved | Aug 10, 2021 to Aug 16, 2021 |
| Combined Radium (-226 and -228) | Resolved | Jan 1, 2021 to Dec 31, 2023 |
| Gross Alpha, Excl. Radon and U | Resolved | Jan 1, 2021 to Dec 31, 2023 |
| 1,2,4-Trichlorobenzene | Archived | Jan 1, 2021 to Dec 31, 2023 |
| cis-1,2-Dichloroethylene | Archived | Jan 1, 2021 to Dec 31, 2023 |
| o-Dichlorobenzene | Archived | Jan 1, 2021 to Dec 31, 2023 |
| p-Dichlorobenzene | Archived | Jan 1, 2021 to Dec 31, 2023 |
| trans-1,2-Dichloroethylene | Archived | Jan 1, 2021 to Dec 31, 2023 |
| 1,2-Dichloroethane | Archived | Jan 1, 2021 to Dec 31, 2023 |
| 1,1,1-Trichloroethane | Archived | Jan 1, 2021 to Dec 31, 2023 |
| Carbon tetrachloride | Archived | Jan 1, 2021 to Dec 31, 2023 |
| 1,2-Dichloropropane | Archived | Jan 1, 2021 to Dec 31, 2023 |
| Trichloroethylene | Archived | Jan 1, 2021 to Dec 31, 2023 |
| CHLOROBENZENE | Archived | Jan 1, 2021 to Dec 31, 2023 |
| Toluene | Archived | Jan 1, 2021 to Dec 31, 2023 |
| Styrene | Archived | Jan 1, 2021 to Dec 31, 2023 |
| 1,1,2-Trichloroethane | Archived | Jan 1, 2021 to Dec 31, 2023 |
| Combined Uranium | Resolved | Jan 1, 2021 to Dec 31, 2023 |
| Ethylbenzene | Archived | Jan 1, 2021 to Dec 31, 2023 |
| DICHLOROMETHANE | Archived | Jan 1, 2021 to Dec 31, 2023 |
| 1,1-Dichloroethylene | Archived | Jan 1, 2021 to Dec 31, 2023 |
| Benzene | Archived | Jan 1, 2021 to Dec 31, 2023 |
| Tetrachloroethylene | Archived | Jan 1, 2021 to Dec 31, 2023 |
| Vinyl chloride | Archived | Jan 1, 2021 to Dec 31, 2023 |
| Consumer Confidence Rule | Unaddressed | Jul 1, 2017 |
Ctwc - Westchester Village
CT0282001 · Groundwater · 252 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
- 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 (0)
No record returned in this imported window. This is not a guarantee of tap-water safety.
Westchester Hills Condominium Assn.
CT0280031 · Groundwater · 225 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
- Reported level
- 0 mg/L
- Action level
- 0.015 mg/L
0% of the listed benchmark
Monitoring period: Jul 1, 2025 to Dec 31, 2025
Violation history (3)
| Rule | Status | Period |
|---|---|---|
| Consumer Confidence Rule | Resolved | Jul 1, 2024 to Jul 2, 2024 |
| Consumer Confidence Rule | Resolved | Jul 1, 2022 to Oct 3, 2022 |
| Lead and Copper Rule | Resolved | Apr 1, 2021 to Sep 20, 2021 |
Colchester Commons
CT0286011 · Groundwater · 224 people served system-wide
The system names this served city; Census place overlap links the city to this ZCTA.
1 reported active health-based record(s) for this system
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
- 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 (4)
| Rule | Status | Period |
|---|---|---|
| Lead and Copper Rule | Resolved | Dec 30, 2024 to Dec 31, 2024 |
| LEAD AND COPPER RULE REVISIONS | Unaddressed | Oct 17, 2024 |
| LEAD AND COPPER RULE REVISIONSHealth-based | Unaddressed | Oct 17, 2024 |
| Revised Total Coliform RuleHealth-based | Resolved | Oct 1, 2022 to Oct 31, 2022 |
Knob Hill Condominiums
CT0280051 · Groundwater · 84 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
- Reported level
- 0 mg/L
- Action level
- 0.015 mg/L
0% of the listed benchmark
Monitoring period: Jul 1, 2025 to Dec 31, 2025
Violation history (14)
| Rule | Status | Period |
|---|---|---|
| Consumer Confidence Rule | Resolved | Jul 1, 2022 to Oct 3, 2022 |
| Arsenic | Resolved | Jan 1, 2022 to Dec 31, 2024 |
| Chromium | Resolved | Jan 1, 2022 to Dec 31, 2024 |
| CYANIDE | Resolved | Jan 1, 2022 to Dec 31, 2024 |
| Mercury | Resolved | Jan 1, 2022 to Dec 31, 2024 |
| Selenium | Resolved | Jan 1, 2022 to Dec 31, 2024 |
| Cadmium | Resolved | Jan 1, 2022 to Dec 31, 2024 |
| Nickel | Resolved | Jan 1, 2022 to Dec 31, 2024 |
| Fluoride | Resolved | Jan 1, 2022 to Dec 31, 2024 |
| Beryllium, Total | Resolved | Jan 1, 2022 to Dec 31, 2024 |
| Antimony, Total | Resolved | Jan 1, 2022 to Dec 31, 2024 |
| Barium | Resolved | Jan 1, 2022 to Dec 31, 2024 |
| Thallium, Total | Resolved | Jan 1, 2022 to Dec 31, 2024 |
| Revised Total Coliform Rule | Resolved | Aug 20, 2021 to Feb 7, 2022 |
Ctwc - Ponemah Village
CT0280071 · Groundwater · 60 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
- Reported level
- 0.0047 mg/L
- Action level
- 0.015 mg/L
31% of the listed benchmark
Monitoring period: Jan 1, 2022 to Dec 31, 2024
Violation history (0)
No record returned in this imported window. This is not a guarantee of tap-water safety.
Hardness meter
What does nearby environmental evidence show?
71.2
PPM as CaCO₃
Moderately Hard
PPM
71.2
GPG
4.2
Regional environmental evidence
USGS hardness classification scale
71.2 PPM
Soft
0–60Moderate
61–120Hard
121–180Very hard
181+
0–60Moderate
61–120Hard
121–180Very hard
181+
Parts per million
71.2
mg/L as CaCO₃ equivalent
Grains per gallon
4.2
1 GPG ≈ 17.1 PPM
How to use regional evidence
These samples describe nearby environmental water. They cannot establish whether your tap water is soft or hard. Use a utility result or a tap test for appliance settings and treatment sizing.
USGS sites used
36
Nearest site
11.9 mi
Observation range
May 17, 2016–Nov 21, 2025
Regional evidence confidence
Moderate
Median of the latest source-type-aligned hardness observation at each monitoring site within 25 miles. Nearest monitoring location: CT-FR 23 (Well).USGS source documentation ↗Evidence tier: Regional environmental evidence. This value is not used as proof of the serving utility's treated-water hardness.
Regional context
Is 06415 typical?
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Colchester median
71 PPM
About the same1 indexed ZIP readings · Range 71.2–71.2 PPM
Connecticut median
89 PPM
18 PPM lower98 indexed ZIP readings · Range 15.8–254 PPM
Evidence-first next steps
Confirm the problem before choosing treatment
This profile can help you ask the right question. It cannot select equipment for a property without a current result from the serving utility or the tap.
Confirm the serving system
ZIP boundaries and utility service areas do not perfectly match. Verify the system on a water bill before relying on system-wide records.
Read the current utility report
An active health-based record is present. Follow the utility's current notice and public-health instructions.
Find an official utility report →Test for the decision you face
Use a tap hardness test before sizing a softener. For health concerns, use a certified laboratory and the correct sampling protocol.
Convert your hardness test result →Frequently asked
Water questions for Colchester
Is tap water safe in Colchester?+
EPA ECHO reports 2 active health-based violations among the associated community water systems. Review the affected utility's current notice and Consumer Confidence Report.
How hard is the water?+
Utility-reported hardness is unavailable in this index. Regional samples do not establish tap-water hardness. Ask your provider or test your tap.
Do I need a water softener?+
Confirm hardness at your tap and consider actual scale or spotting before choosing treatment. Regional environmental values cannot determine whether you need a softener. A softener addresses hardness, not every contaminant.