MASHANTUCKET, 01

Mashantucket Pequot Water System Water System

Current status

No open violations on record as of July 4, 2026.

This system's next federally required Consumer Confidence Report is due July 1, 2027, under the EPA's revised reporting rule.

Data sourced from the EPA ECHO database (SDWA bulk download), last refreshed July 4, 2026. This is a record-keeping and public-information tool — it does not replace EPA Region 1’s official records. Always confirm current status with EPA Region 1 before making decisions based on this information.

System facts

System ID (PWSID): 010106001
System type: Community Water System
Population served: 26,445
Service connections: 154
Ownership: Native American tribal
Water source: surface water (rivers, lakes, or reservoirs)

Violation history

Consumer Confidence Report Inadequate Reporting
—
Consumer Confidence Rule
July 1, 2025 – October 2, 2025
Resolved
Consumer Confidence Report Inadequate Reporting
—
Consumer Confidence Rule
July 1, 2024 – October 2, 2025
Resolved
Report Sample Result/Fail Monitor (RTCR)
—
Revised Total Coliform Rule
November 1, 2018 – January 8, 2019
Resolved
Maximum Contaminant Level Violation, Average
Health-based
TTHM
October 1, 2018 – December 31, 2018
Resolved
Public Notification Violation for NPDWR Violation
—
Public Notice
September 28, 2018 – December 27, 2018
Resolved
Failure Submit IDSE/Subpart V Plan Rpt
—
TTHM
August 9, 2018 – December 26, 2018
Resolved
Failure Submit IDSE/Subpart V Plan Rpt
—
TTHM
July 1, 2018 – December 26, 2018
Resolved
Maximum Contaminant Level Violation, Average
Health-based
TTHM
July 1, 2018 – September 30, 2018
Resolved
Monitoring, Regular
—
Glyphosate
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Di(2-ethylhexyl) adipate
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
OXAMYL
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Simazine
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Di(2-ethylhexyl) phthalate
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Picloram
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Dinoseb
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Hexachlorocyclopentadiene
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Carbofuran
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Atrazine
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
LASSO
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Heptachlor
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Heptachlor epoxide
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
2,4-D
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
2,4,5-TP
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
HEXACHLOROBENZENE
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Benzo(a)pyrene
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Pentachlorophenol
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Total Polychlorinated Biphenyls (PCB)
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
ETHYLENE DIBROMIDE
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Chlordane
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
1,2-DIBROMO-3-CHLOROPROPANE
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Endrin
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
BHC-GAMMA
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Methoxychlor
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Toxaphene
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Dalapon
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Diquat
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Regular
—
Endothall
January 1, 2016 – December 31, 2016
Resolved
Monitoring, Routine Minor (TCR)
—
Coliform (TCR)
November 1, 1993 – November 30, 1993
Resolved
Water Quality Parameter M/R
—
Lead and Copper Rule
July 1, 1993 – December 31, 1993
Resolved
Water Quality Parameter M/R
—
Lead and Copper Rule
July 1, 1993 – December 31, 1993
Resolved
Maximum Contaminant Level Violation, Acute (TCR)
Health-based
Coliform (TCR)
February 1, 1993 – February 28, 1993
Resolved
Maximum Contaminant Level Violation, Acute (TCR)
Health-based
Coliform (TCR)
January 1, 1993 – January 31, 1993
Resolved
Maximum Contaminant Level Violation, Acute (TCR)
Health-based
Coliform (TCR)
December 1, 1992 – December 31, 1992
Resolved
Maximum Contaminant Level Violation, Acute (TCR)
Health-based
Coliform (TCR)
November 1, 1992 – November 30, 1992
Resolved
Maximum Contaminant Level Violation, Acute (TCR)
Health-based
Coliform (TCR)
March 1, 1992 – March 18, 1992
Resolved
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
January 1, 1992 – January 31, 1992
Resolved

Resolved addressed and confirmed by the state

Period	Violation	Contaminant / rule	Health-based	Status
July 1, 2025 – October 2, 2025	Consumer Confidence Report Inadequate Reporting	Consumer Confidence Rule	—	Resolved
July 1, 2024 – October 2, 2025	Consumer Confidence Report Inadequate Reporting	Consumer Confidence Rule	—	Resolved
November 1, 2018 – January 8, 2019	Report Sample Result/Fail Monitor (RTCR)	Revised Total Coliform Rule	—	Resolved
October 1, 2018 – December 31, 2018	Maximum Contaminant Level Violation, Average	TTHM	Health-based	Resolved
September 28, 2018 – December 27, 2018	Public Notification Violation for NPDWR Violation	Public Notice	—	Resolved
August 9, 2018 – December 26, 2018	Failure Submit IDSE/Subpart V Plan Rpt	TTHM	—	Resolved
July 1, 2018 – December 26, 2018	Failure Submit IDSE/Subpart V Plan Rpt	TTHM	—	Resolved
July 1, 2018 – September 30, 2018	Maximum Contaminant Level Violation, Average	TTHM	Health-based	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Glyphosate	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Di(2-ethylhexyl) adipate	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	OXAMYL	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Simazine	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Di(2-ethylhexyl) phthalate	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Picloram	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Dinoseb	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Hexachlorocyclopentadiene	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Carbofuran	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Atrazine	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	LASSO	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Heptachlor	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Heptachlor epoxide	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	2,4-D	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	2,4,5-TP	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	HEXACHLOROBENZENE	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Benzo(a)pyrene	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Pentachlorophenol	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Total Polychlorinated Biphenyls (PCB)	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	ETHYLENE DIBROMIDE	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Chlordane	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	1,2-DIBROMO-3-CHLOROPROPANE	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Endrin	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	BHC-GAMMA	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Methoxychlor	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Toxaphene	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Dalapon	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Diquat	—	Resolved
January 1, 2016 – December 31, 2016	Monitoring, Regular	Endothall	—	Resolved
November 1, 1993 – November 30, 1993	Monitoring, Routine Minor (TCR)	Coliform (TCR)	—	Resolved
July 1, 1993 – December 31, 1993	Water Quality Parameter M/R	Lead and Copper Rule	—	Resolved
July 1, 1993 – December 31, 1993	Water Quality Parameter M/R	Lead and Copper Rule	—	Resolved
February 1, 1993 – February 28, 1993	Maximum Contaminant Level Violation, Acute (TCR)	Coliform (TCR)	Health-based	Resolved
January 1, 1993 – January 31, 1993	Maximum Contaminant Level Violation, Acute (TCR)	Coliform (TCR)	Health-based	Resolved
December 1, 1992 – December 31, 1992	Maximum Contaminant Level Violation, Acute (TCR)	Coliform (TCR)	Health-based	Resolved
November 1, 1992 – November 30, 1992	Maximum Contaminant Level Violation, Acute (TCR)	Coliform (TCR)	Health-based	Resolved
March 1, 1992 – March 18, 1992	Maximum Contaminant Level Violation, Acute (TCR)	Coliform (TCR)	Health-based	Resolved
January 1, 1992 – January 31, 1992	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Resolved

Resolved addressed and confirmed by the state

Enforcement actions

October 2, 2025Federal Public Notification received from PWS1 linked violation
October 2, 2025Federal Public Notification received from PWS1 linked violation
October 2, 2025Federal Compliance achieved1 linked violation
October 2, 2025Federal Compliance achieved1 linked violation
September 26, 2025Federal Public Notification issued1 linked violation
September 26, 2025Federal Public Notification issued1 linked violation
February 12, 2019Federal Compliance achieved1 linked violation
February 12, 2019Federal Compliance achieved1 linked violation
January 8, 2019Federal Compliance achieved1 linked violation
December 27, 2018Federal Public Notification received from PWS1 linked violation
December 27, 2018Federal Public Notification received from PWS1 linked violation
December 27, 2018Federal Public Notification received from PWS1 linked violation
December 27, 2018Federal Public Notification received from PWS1 linked violation
December 27, 2018Federal Public Notification received from PWS1 linked violation
December 27, 2018Federal Compliance achieved1 linked violation
December 26, 2018Federal Compliance achieved1 linked violation
December 26, 2018Federal Compliance achieved1 linked violation
December 3, 2018Federal Public Notification requested1 linked violation
December 3, 2018Federal Public Notification requested1 linked violation
December 3, 2018Federal Public Notification requested1 linked violation
December 3, 2018Federal Public Notification requested1 linked violation
December 3, 2018Federal Public Notification requested1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
August 3, 2017Federal Compliance achieved1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
July 13, 2017Federal Violation/Reminder Notice1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 30, 2017Federal Public Notification received from PWS1 linked violation
June 2, 1998Federal Compliance achieved1 linked violation
June 2, 1998Federal Compliance achieved1 linked violation
June 2, 1998Federal Compliance achieved1 linked violation
June 2, 1998Federal Compliance achieved1 linked violation
June 2, 1998Federal Compliance achieved1 linked violation
February 20, 1998Federal Compliance Meeting conducted1 linked violation
February 20, 1998Federal Compliance Meeting conducted1 linked violation
March 22, 1994Federal Violation/Reminder Notice1 linked violation
February 18, 1994Federal Violation/Reminder Notice1 linked violation
January 28, 1994Federal Compliance achieved1 linked violation
January 10, 1994Federal Compliance achieved1 linked violation
December 10, 1993Federal Violation/Reminder Notice1 linked violation
December 9, 1993Federal Violation/Reminder Notice1 linked violation
March 9, 1993Federal Technical Assistance Visit1 linked violation
March 9, 1993Federal Technical Assistance Visit1 linked violation
March 9, 1993Federal Technical Assistance Visit1 linked violation
March 9, 1993Federal Technical Assistance Visit1 linked violation
February 26, 1993Federal Violation/Reminder Notice1 linked violation
February 26, 1993Federal Violation/Reminder Notice1 linked violation
February 26, 1993Federal Violation/Reminder Notice1 linked violation
February 26, 1993Federal Violation/Reminder Notice1 linked violation
February 16, 1993Federal Violation/Reminder Notice1 linked violation
February 16, 1993Federal Violation/Reminder Notice1 linked violation
February 16, 1993Federal Violation/Reminder Notice1 linked violation
February 16, 1993Federal Violation/Reminder Notice1 linked violation
February 12, 1993Federal Violation/Reminder Notice1 linked violation
February 12, 1993Federal Violation/Reminder Notice1 linked violation
February 12, 1993Federal Violation/Reminder Notice1 linked violation
February 12, 1993Federal Violation/Reminder Notice1 linked violation
February 10, 1993Federal Violation/Reminder Notice1 linked violation
February 10, 1993Federal Violation/Reminder Notice1 linked violation
February 10, 1993Federal Violation/Reminder Notice1 linked violation
February 10, 1993Federal Violation/Reminder Notice1 linked violation
February 9, 1993Federal Violation/Reminder Notice1 linked violation
February 9, 1993Federal Violation/Reminder Notice1 linked violation
February 9, 1993Federal Violation/Reminder Notice1 linked violation
February 9, 1993Federal Violation/Reminder Notice1 linked violation
February 1, 1993Federal issued Boil Water Order1 linked violation
February 1, 1993Federal Violation/Reminder Notice1 linked violation
February 1, 1993Federal Violation/Reminder Notice1 linked violation
February 1, 1993Federal Violation/Reminder Notice1 linked violation
February 1, 1993Federal Violation/Reminder Notice1 linked violation
February 1, 1993Federal issued Boil Water Order1 linked violation
February 1, 1993Federal issued Boil Water Order1 linked violation
February 1, 1993Federal issued Boil Water Order1 linked violation
January 12, 1993Federal Violation/Reminder Notice1 linked violation
January 12, 1993Federal Violation/Reminder Notice1 linked violation
January 12, 1993Federal Violation/Reminder Notice1 linked violation
January 12, 1993Federal Violation/Reminder Notice1 linked violation
January 5, 1993Federal Violation/Reminder Notice1 linked violation
January 5, 1993Federal Violation/Reminder Notice1 linked violation
January 5, 1993Federal Violation/Reminder Notice1 linked violation
January 5, 1993Federal Violation/Reminder Notice1 linked violation
December 17, 1992Federal Violation/Reminder Notice1 linked violation
December 17, 1992Federal Violation/Reminder Notice1 linked violation
December 17, 1992Federal Violation/Reminder Notice1 linked violation
December 17, 1992Federal Violation/Reminder Notice1 linked violation
December 16, 1992Federal Violation/Reminder Notice1 linked violation
December 16, 1992Federal Violation/Reminder Notice1 linked violation
December 16, 1992Federal Violation/Reminder Notice1 linked violation
December 16, 1992Federal Violation/Reminder Notice1 linked violation
March 18, 1992Federal Compliance achieved1 linked violation
March 6, 1992Federal Public Notification received from PWS1 linked violation
March 5, 1992Federal Public Notification requested1 linked violation
March 5, 1992Federal issued Boil Water Order1 linked violation
March 5, 1992Federal issued Formal Notice of Violation1 linked violation
February 24, 1992Federal Violation/Reminder Notice1 linked violation
February 24, 1992Federal Compliance achieved1 linked violation
February 10, 1992Federal Violation/Reminder Notice1 linked violation

Contact

Mashantucket Pequot Tribal Utilities

8603966740

MASHANTUCKET, CT 06339-3060