Public water system record
Mashantucket Pequot Water System
Serves Pawcatuck, Southeastern Connecticut Planning Region, CT · 26,445 people served
Federal records show 2 health-based violations and 36 monitoring/reporting issues for Mashantucket Pequot Water System in the last ten years. The most serious issue in this window was a resolved Total Trihalomethanes (TTHMs) violation.
System profile
- Health-based violations, last 10 years
- 2
- Resolved
- 2
- Unresolved
- 0
- Any acute record
- No
- Monitoring issues, last 10 years
- 36
Key facts
- Mashantucket Pequot Water System draws water from 5 wells.
- Highest measured level in the last 10 years: Total Trihalomethanes (TTHMs), 0.088 mg/L, federal limit 0.08 mg/L (1.1 times the limit), 2018.
- Most recent enforcement action: boil water order by EPA, February 1993.
- Record on file since 1992, with 5 health-based violations before October 19, 2016.
- Lead pipe inventory: 0 lead and 0 unknown out of 154 service lines.
Check whether Mashantucket Pequot Water System serves your address
Health-based violations
Since October 2016Violation data reflects EPA records through March 2026. For the most current status, visit the EPA ECHO database.
| Contaminant | Rule family | Start date | Status | Acute |
|---|---|---|---|---|
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.0839 mg/L, federal limit 0.08 mg/L (at or just above the limit)
|
220 | Oct 1, 2018 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.088 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
|
220 | Jul 1, 2018 | Resolved | No |
Monitoring and reporting issues
Since October 2016Missed tests or reports, not contaminants found above a limit.
| Issue | Start date | Status |
|---|---|---|
|
Consumer Confidence Rule
OTHER
|
Jul 1, 2025 | Resolved |
|
Consumer Confidence Rule
OTHER
|
Jul 1, 2024 | Resolved |
|
Revised Total Coliform Rule
RPT
|
Nov 1, 2018 | Resolved |
|
Public Notice
OTHER
|
Sep 28, 2018 | Resolved |
|
Total Trihalomethanes (TTHMs)
Monitoring and reporting
|
Aug 9, 2018 | Resolved |
|
Total Trihalomethanes (TTHMs)
Monitoring and reporting
|
Jul 1, 2018 | Resolved |
|
Public Notice
OTHER
|
Apr 2, 2018 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
|
Chlordane
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
ETHYLENE DIBROMIDE
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
1,2-DIBROMO-3-CHLOROPROPANE
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Total Polychlorinated Biphenyls (PCB)
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Pentachlorophenol
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Benzo(a)pyrene
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
HEXACHLOROBENZENE
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
2,4,5-TP
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
2,4-D
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Heptachlor epoxide
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Heptachlor
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
LASSO
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Atrazine
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Carbofuran
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Hexachlorocyclopentadiene
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Dinoseb
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Picloram
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Di(2-ethylhexyl) phthalate
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Simazine
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
OXAMYL
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Di(2-ethylhexyl) adipate
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Glyphosate
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Endothall
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Diquat
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Dalapon
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Toxaphene
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Methoxychlor
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
BHC-GAMMA
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
|
Endrin
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
Full record since 1992
EPA's records for Mashantucket Pequot Water System go back to 1992. Before October 19, 2016 they list 5 health-based violations (5 resolved) and 33 monitoring or reporting violations.
| Violations that began in | Health-based | Monitoring and reporting |
|---|---|---|
| 1990s | 5 | 4 |
| 2010 to October 18, 2016 | 0 | 29 |
| October 19, 2016 to 2019 | 2 | 5 |
| 2020s | 0 | 2 |
Most recent health-based violation before October 19, 2016: Total Coliform (acute), began February 1993, Resolved.
Show all 5 health-based violations before October 19, 2016
| Contaminant | Start date | Status |
|---|---|---|
|
Total Coliform (acute)
Contaminant limit exceeded
|
Feb 1, 1993 | Resolved |
|
Total Coliform (acute)
Contaminant limit exceeded
|
Jan 1, 1993 | Resolved |
|
Total Coliform (acute)
Contaminant limit exceeded
|
Dec 1, 1992 | Resolved |
|
Total Coliform (acute)
Contaminant limit exceeded
|
Nov 1, 1992 | Resolved |
|
Total Coliform (acute)
Contaminant limit exceeded
|
Mar 1, 1992 | Resolved |
Enforcement actions
EPA issued 2 boil water orders to Mashantucket Pequot Water System between 1992 and 1993, filed as 5 records in EPA's data. The most recent was a boil water order in February 1993.
| Date | By | Action | Violations covered |
|---|---|---|---|
| Feb 1, 1993 | EPA | Boil water order | 4 violations (4 health-based): Total Coliform |
| Mar 5, 1992 | EPA | Boil water order | 1 violation (1 health-based): Total Coliform |
What the violations mean
Total Trihalomethanes (TTHMs)
2 incidentsDisinfection byproduct levels exceeded the federal limit
Long-term TTHM exposure may increase bladder cancer risk
Where the water comes from
Mashantucket Pequot Water System draws water from 5 wells.
Annual water quality report
Mashantucket Pequot Water System must give its customers an annual water quality report (Consumer Confidence Report) by July 1, with the levels its tests found in the previous year.
Systems serving 10,000 or more people must mail or deliver the report to every customer, and from 2027 they must send it twice a year.
Find a posted report with EPA's Consumer Confidence Report search
Testing your own water
To test the water at your tap, or a private well this record does not cover, use a laboratory certified for drinking water by EPA Region 1.
Certified drinking water labs by state EPA guidance for private wells