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Community Water System · PWS CT0520011

Ctwc - Unionville System

Clinton, Connecticut 06413 - drinking water served from surface water sources to 14,693 people, tracked in EPA SDWIS and UCMR5.

14,693
People served
27
EPA violations
8
Health-based
6 PFAS
UCMR5 result

The verdict

EPA records 27 drinking-water violations at Ctwc - Unionville System, 30% of them health-based - below the Connecticut per-system average, and UCMR5 testing detected 6 PFAS compounds.

27
Total EPA violations on record
30%
Health-based (MCL / treatment failure)
14,693
People served by this system
6
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Ctwc - Unionville System

Ctwc - Unionville System is a private-owned community water system that delivers drinking water to 14,693 residents in Clinton, Connecticut (Hartford County) through 6,319 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 27 total violations for this system , of which 8 (30%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 9 monitoring and reporting violations are on file. The most recent violation on record dates to 2019.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 7 violations (MR). Under EPA's UCMR5 PFAS monitoring program, 6 PFAS compounds were detected in samples collected from this system, with a maximum reported concentration of 7 ppt (parts per trillion). PFAS are persistent synthetic chemicals linked to health effects at very low exposure levels.

Across Connecticut, EPA tracks 2,332 public water systems serving 2,886,005 people, with 206,662 cumulative violations and 21,779 health-based violations on record. About 94% of systems in the state carry at least one violation, and state-wide the average per system is 88.6 violations. Statewide, 40 of 63 UCMR5-tested systems have reported PFAS detections (63.5%).

Ctwc - Unionville System's 27 violations sit below the Connecticut average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

PFAS Detected

6 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.

Population Served
14,693
Total Violations
27
Health-Based Violations
8
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Private
Connections
6,319
County
Hartford
School/Daycare
No
MCL Violations
4
Monitoring Violations
9
Treatment Tech Violations
4

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 7 1999
Coliform (TCR) MCL 4 2002
Groundwater Rule TT 4 2019
Lead and Copper Rule MR 2 2016

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 12 of 290 samples detected PFAS.

Contaminant Date Result MRL Status
PFUnA 9/19/2023 <2.00 ppt 2.00 ppt Not Detected
PFOS 9/19/2023 6.00 ppt 4.00 ppt Detected
PFHxA 9/19/2023 4.00 ppt 3.00 ppt Detected
PFDoA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
11Cl-PF3OUdS 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
PFDA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFOA 9/19/2023 6.00 ppt 4.00 ppt Detected
PFNA 9/19/2023 <4.00 ppt 4.00 ppt Not Detected
PFHxS 9/19/2023 3.00 ppt 3.00 ppt Detected
PFHpA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFBS 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
NMeFOSAA 9/19/2023 <6.00 ppt 6.00 ppt Not Detected
NEtFOSAA 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 9/19/2023 <7.00 ppt 7.00 ppt Not Detected
9Cl-PF3ONS 9/19/2023 <2.00 ppt 2.00 ppt Not Detected
PFEESA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
ADONA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpS 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeS 9/19/2023 <4.00 ppt 4.00 ppt Not Detected
NFDHA 9/19/2023 <20.00 ppt 20.00 ppt Not Detected
PFTA 9/19/2023 <8.00 ppt 8.00 ppt Not Detected
PFMBA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeA 9/19/2023 4.00 ppt 3.00 ppt Detected
PFMPA 9/19/2023 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
PFBA 9/19/2023 7.00 ppt 5.00 ppt Detected
HFPO-DA 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
PFPeA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
PFBA 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
6:2 FTS 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFBS 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFMPA 9/19/2023 <4.00 ppt 4.00 ppt Not Detected
PFMBA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFEESA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 9/19/2023 <20.00 ppt 20.00 ppt Not Detected
PFPeS 9/19/2023 <4.00 ppt 4.00 ppt Not Detected
PFHpS 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 9/19/2023 <5.00 ppt 5.00 ppt Not Detected
9Cl-PF3ONS 9/19/2023 <2.00 ppt 2.00 ppt Not Detected
PFHxS 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
PFUnA 9/19/2023 <2.00 ppt 2.00 ppt Not Detected
PFDoA 9/19/2023 <3.00 ppt 3.00 ppt Not Detected
NMeFOSAA 9/19/2023 <6.00 ppt 6.00 ppt Not Detected
PFTA 9/19/2023 <8.00 ppt 8.00 ppt Not Detected
PFTrDA 9/19/2023 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 9/19/2023 <5.00 ppt 5.00 ppt Not Detected

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Ctwc - Unionville System.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID CT0520011 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Connecticut Drinking Water Authority

Connecticut's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.

Find CT regulator via EPA SDWIS

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2019 Groundwater Rule TT 4 SDWIS / CT0520011 / 0700
2016 Lead and Copper Rule MR 2 SDWIS / CT0520011 / 5000
2002 Coliform (TCR) MCL 4 SDWIS / CT0520011 / 3100
1999 Coliform (TCR) MR 7 SDWIS / CT0520011 / 3100

How Ctwc - Unionville System Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Ctwc - Unionville System Connecticut avg Federal benchmark
Total violations 27 88.6 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 8 9.3 Indicates a contaminant exceeded a federal MCL
PFAS detection 6 compounds 63.5% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 14,693 1,238 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 2,332 regulated public water systems in Connecticut.

Federal MCL reference, Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Ctwc - Unionville System water safe to drink? ▼
Ctwc - Unionville System (PWS ID: CT0520011) has 27 recorded violations in the EPA SDWIS database. PFAS contamination has been detected in UCMR5 testing, with 6 PFAS compounds found. This system serves 14,693 people using Surface Water sources.
How many people does Ctwc - Unionville System serve? ▼
Ctwc - Unionville System serves 14,693 people in Clinton, Connecticut. It is a Private-owned system using Surface Water water sources with 6,319 service connections.
What type of violations does Ctwc - Unionville System have? ▼
Ctwc - Unionville System has 27 total violations: 8 health-based violations (MCL exceedances or treatment failures), 9 monitoring/reporting violations, and 4 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Ctwc - Unionville System water? ▼
Yes. UCMR5 testing detected 6 PFAS compounds in Ctwc - Unionville System's water supply: PFOS, PFHxA, PFOA, PFHxS, PFPeA, and others. PFAS are persistent "forever chemicals" that do not break down in the environment.
What water source does Ctwc - Unionville System use? ▼
Ctwc - Unionville System uses Surface Water as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. PFAS data from EPA UCMR5 monitoring program (2023-2025). This data is provided for informational purposes only.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.