Is HIDDEN LAKE YELLOWSTONE COUNTY W AND S D required to publish a Consumer Confidence Report?

Yes. HIDDEN LAKE YELLOWSTONE COUNTY W AND S D is a community water system, and federal rules (40 CFR 141 Subpart O) require every community water system to publish a Consumer Confidence Report each year.

When is HIDDEN LAKE YELLOWSTONE COUNTY W AND S D’s next Consumer Confidence Report due?

HIDDEN LAKE YELLOWSTONE COUNTY W AND S D’s next Consumer Confidence Report is due by July 1, 2027. The report covers calendar year 2026.

What is a Consumer Confidence Report?

A Consumer Confidence Report (CCR) is the annual drinking water quality report that community water systems must provide to the people they serve. It lists the contaminants detected in the system’s water during the year, where the water comes from, and how the results compare with federal limits. EPA’s revised CCR rule takes effect January 1, 2027, and the first reports in the new format are due July 1, 2027.

BILLINGS, MT · Yellowstone County

HIDDEN LAKE YELLOWSTONE COUNTY W AND S D Water System

Consumer Confidence Report status

HIDDEN LAKE YELLOWSTONE COUNTY W AND S D must publish a Consumer Confidence Report — the annual drinking water quality report covering calendar year 2026 — by July 1, 2027.

As of August 1, 2026, EPA's federal records show no open violations for HIDDEN LAKE YELLOWSTONE COUNTY W AND S D.

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

System facts

System ID (PWSID): MT0003374
System type: Community Water System
Population served: 350
Service connections: 113
Ownership: local government
Water source: groundwater (wells)

HIDDEN LAKE YELLOWSTONE COUNTY W AND S D is one of 1,084 community water systems in Montana in the 500 or fewer people size category, serving 350 people from groundwater.

As of August 1, 2026, its federal record holds 63 entries between 1992 and 2023, all of which EPA lists as closed. Nothing has been added since 2023.

Of the 63, 60 are monitoring and reporting requirements — the category that accounts for about four in five of all violations in EPA's national dataset — rather than findings about the water itself. The record involves volatile organic chemicals, inorganic chemicals, and the Total Coliform Rules.

Violation history

Monitoring of Treatment (SWTR-Unfilt/GWR)
—
Groundwater Rule
November 1, 2023 – January 3, 2023
Resolved
Monitoring of Treatment (SWTR-Unfilt/GWR)
—
Groundwater Rule
August 1, 2021 – August 31, 2021
Resolved
Monitoring of Treatment (SWTR-Unfilt/GWR)
—
Groundwater Rule
April 1, 2020 – April 30, 2020
Resolved
Monitoring, Regular
—
Toluene
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
Benzene
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
CHLOROBENZENE
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
Tetrachloroethylene
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
1,1,2-Trichloroethane
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
Trichloroethylene
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
Styrene
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
Ethylbenzene
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
Vinyl chloride
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
1,1-Dichloroethylene
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
trans-1,2-Dichloroethylene
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
1,2-Dichloroethane
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
1,1,1-Trichloroethane
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
Carbon tetrachloride
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
1,2-Dichloropropane
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
1,2,4-Trichlorobenzene
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
cis-1,2-Dichloroethylene
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
Xylenes, Total
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
DICHLOROMETHANE
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
o-Dichlorobenzene
January 1, 2020 – December 31, 2022
Resolved
Monitoring, Regular
—
p-Dichlorobenzene
January 1, 2020 – December 31, 2022
Resolved
Consumer Confidence Report Complete Failure to Report
—
Consumer Confidence Rule
July 1, 2017 – July 25, 2017
Resolved
Monitoring of Treatment (SWTR-Unfilt/GWR)
—
Groundwater Rule
July 1, 2017 – July 31, 2017
Resolved
Maximum Contaminant Level Violation, Monthly (TCR)
Health-based
Coliform (TCR)
July 1, 2015 – July 31, 2015
Resolved
Maximum Contaminant Level Violation, Acute (TCR)
Health-based
Coliform (TCR)
July 1, 2015 – July 31, 2015
Resolved
Lead Consumer Notice
—
Lead and Copper Rule
December 30, 2014 – February 5, 2015
Resolved
Monitoring and Reporting (DBP)
—
Chlorine
January 1, 2012 – March 31, 2012
Resolved
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
November 1, 2007 – November 30, 2007
Resolved
Follow-up Or Routine LCR Tap M/R
—
Lead and Copper Rule
October 1, 2004 – July 23, 2007
Resolved
Monitoring, Regular
—
Nitrate-Nitrite
January 1, 2004 – December 31, 2004
Resolved
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
June 1, 1999 – June 30, 1999
Resolved
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
December 1, 1998 – December 31, 1998
Resolved
Monitoring, Regular
—
Nitrate
January 1, 1998 – December 31, 1998
Resolved
Monitoring, Regular
—
Nitrate
January 1, 1997 – December 31, 1997
Resolved
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
August 1, 1996 – August 31, 1996
Resolved
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
February 1, 1996 – February 29, 1996
Resolved
Monitoring, Regular
—
OXAMYL
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Heptachlor epoxide
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Aldicarb
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
LASSO
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
2,4,5-TP
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Methoxychlor
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Endrin
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
January 1, 1996 – January 31, 1996
Resolved
Monitoring, Regular
—
1,1,2-Trichloroethane
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Ethylbenzene
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
1,2-Dichloroethane
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Thallium, Total
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Nickel
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Beryllium, Total
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Antimony, Total
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Xylenes, Total
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Benzo(a)pyrene
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Picloram
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Barium
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Arsenic
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Chromium
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Regular
—
Cadmium
January 1, 1996 – December 31, 1998
Resolved
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
October 1, 1995 – October 31, 1995
Resolved
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
August 1, 1992 – August 31, 1992
Resolved

Resolved addressed and confirmed by the state

Period	Violation	Contaminant / rule	Health-based	Status
November 1, 2023 – January 3, 2023	Monitoring of Treatment (SWTR-Unfilt/GWR)	Groundwater Rule	—	Resolved
August 1, 2021 – August 31, 2021	Monitoring of Treatment (SWTR-Unfilt/GWR)	Groundwater Rule	—	Resolved
April 1, 2020 – April 30, 2020	Monitoring of Treatment (SWTR-Unfilt/GWR)	Groundwater Rule	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	Toluene	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	Benzene	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	CHLOROBENZENE	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	Tetrachloroethylene	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	1,1,2-Trichloroethane	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	Trichloroethylene	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	Styrene	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	Ethylbenzene	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	Vinyl chloride	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	1,1-Dichloroethylene	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	trans-1,2-Dichloroethylene	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	1,2-Dichloroethane	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	1,1,1-Trichloroethane	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	Carbon tetrachloride	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	1,2-Dichloropropane	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	1,2,4-Trichlorobenzene	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	cis-1,2-Dichloroethylene	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	Xylenes, Total	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	DICHLOROMETHANE	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	o-Dichlorobenzene	—	Resolved
January 1, 2020 – December 31, 2022	Monitoring, Regular	p-Dichlorobenzene	—	Resolved
July 1, 2017 – July 25, 2017	Consumer Confidence Report Complete Failure to Report	Consumer Confidence Rule	—	Resolved
July 1, 2017 – July 31, 2017	Monitoring of Treatment (SWTR-Unfilt/GWR)	Groundwater Rule	—	Resolved
July 1, 2015 – July 31, 2015	Maximum Contaminant Level Violation, Monthly (TCR)	Coliform (TCR)	Health-based	Resolved
July 1, 2015 – July 31, 2015	Maximum Contaminant Level Violation, Acute (TCR)	Coliform (TCR)	Health-based	Resolved
December 30, 2014 – February 5, 2015	Lead Consumer Notice	Lead and Copper Rule	—	Resolved
January 1, 2012 – March 31, 2012	Monitoring and Reporting (DBP)	Chlorine	—	Resolved
November 1, 2007 – November 30, 2007	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Resolved
October 1, 2004 – July 23, 2007	Follow-up Or Routine LCR Tap M/R	Lead and Copper Rule	—	Resolved
January 1, 2004 – December 31, 2004	Monitoring, Regular	Nitrate-Nitrite	—	Resolved
June 1, 1999 – June 30, 1999	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Resolved
December 1, 1998 – December 31, 1998	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Resolved
January 1, 1998 – December 31, 1998	Monitoring, Regular	Nitrate	—	Resolved
January 1, 1997 – December 31, 1997	Monitoring, Regular	Nitrate	—	Resolved
August 1, 1996 – August 31, 1996	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Resolved
February 1, 1996 – February 29, 1996	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	OXAMYL	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Heptachlor epoxide	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Aldicarb	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	LASSO	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	2,4,5-TP	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Methoxychlor	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Endrin	—	Resolved
January 1, 1996 – January 31, 1996	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	1,1,2-Trichloroethane	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Ethylbenzene	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	1,2-Dichloroethane	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Thallium, Total	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Nickel	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Beryllium, Total	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Antimony, Total	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Xylenes, Total	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Benzo(a)pyrene	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Picloram	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Barium	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Arsenic	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Chromium	—	Resolved
January 1, 1996 – December 31, 1998	Monitoring, Regular	Cadmium	—	Resolved
October 1, 1995 – October 31, 1995	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Resolved
August 1, 1992 – August 31, 1992	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Resolved

Resolved addressed and confirmed by the state

Enforcement actions

January 9, 2024State Public Notification received1 linked violation
December 27, 2023State Violation/Reminder Notice1 linked violation
December 27, 2023State Public Notification requested1 linked violation
February 16, 2023State Compliance achieved21 linked violations
February 16, 2023State Compliance achieved21 linked violations
February 16, 2023State Compliance achieved21 linked violations
February 16, 2023State Compliance achieved21 linked violations
February 16, 2023State Compliance achieved21 linked violations
February 16, 2023State Compliance achieved21 linked violations
February 7, 2023State Public Notification received21 linked violations
January 29, 2023State Violation/Reminder Notice21 linked violations
January 29, 2023State Public Notification requested21 linked violations
January 29, 2023State Public Notification requested21 linked violations
January 29, 2023State Violation/Reminder Notice21 linked violations
January 29, 2023State Public Notification requested21 linked violations
January 29, 2023State Violation/Reminder Notice21 linked violations
January 29, 2023State Public Notification requested21 linked violations
January 29, 2023State Violation/Reminder Notice21 linked violations
January 29, 2023State Public Notification requested21 linked violations
January 29, 2023State Violation/Reminder Notice21 linked violations
January 29, 2023State Public Notification requested21 linked violations
January 29, 2023State Violation/Reminder Notice21 linked violations
January 3, 2023State Compliance achieved1 linked violation
September 23, 2021State Compliance achieved1 linked violation
September 23, 2021State Public Notification received1 linked violation
September 15, 2021State Public Notification requested1 linked violation
September 15, 2021State Violation/Reminder Notice1 linked violation
June 8, 2020State Compliance achieved1 linked violation
June 8, 2020State Public Notification received1 linked violation
May 21, 2020State Public Notification requested1 linked violation
May 21, 2020State Violation/Reminder Notice1 linked violation
August 21, 2017State Public Notification received1 linked violation
August 15, 2017State Compliance achieved1 linked violation
August 14, 2017State Violation/Reminder Notice1 linked violation
August 14, 2017State Public Notification requested1 linked violation
July 25, 2017State Compliance achieved1 linked violation
July 20, 2017State Violation/Reminder Notice1 linked violation
August 3, 2015State Compliance achieved1 linked violation
August 3, 2015State Compliance achieved1 linked violation
July 20, 2015State Public Notification received1 linked violation
July 17, 2015State Violation/Reminder Notice1 linked violation
July 17, 2015State Public Notification requested1 linked violation
July 17, 2015State Violation/Reminder Notice1 linked violation
July 16, 2015State Boil Water Order1 linked violation
July 16, 2015State Public Notification requested1 linked violation
July 16, 2015State Public Notification received1 linked violation
July 16, 2015State Public Notification requested1 linked violation
July 16, 2015State Violation/Reminder Notice1 linked violation
July 16, 2015State Violation/Reminder Notice1 linked violation
February 5, 2015State Compliance achieved1 linked violation
January 26, 2015State Violation/Reminder Notice1 linked violation
February 19, 2013State Compliance achieved1 linked violation
April 25, 2012State Public Notification received1 linked violation
April 13, 2012State Violation/Reminder Notice1 linked violation
April 13, 2012State Public Notification requested1 linked violation
June 16, 2011State Compliance achieved1 linked violation
November 23, 2010State Public Notification received1 linked violation
October 30, 2010State Public Notification requested1 linked violation
October 30, 2010State Violation/Reminder Notice1 linked violation
January 6, 2009State Compliance achieved12 linked violations
January 11, 2008State Public Notification received1 linked violation
December 19, 2007State Compliance achieved1 linked violation
December 19, 2007State Violation/Reminder Notice1 linked violation
December 19, 2007State Public Notification requested1 linked violation
July 23, 2007State Compliance achieved2 linked violations
January 4, 2005State Public Notification requested1 linked violation
March 9, 2001State Compliance achieved70 linked violations
May 19, 2000State Other2 linked violations
May 19, 2000State Other1 linked violation
May 19, 2000State Other1 linked violation
May 18, 2000State Othergeneral compliance action — not tied to a specific violation on record
May 18, 2000State Othergeneral compliance action — not tied to a specific violation on record
May 18, 2000State Othergeneral compliance action — not tied to a specific violation on record
May 18, 2000State Other79 linked violations
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other3 linked violations
May 18, 2000State Other1 linked violation
May 18, 2000State Othergeneral compliance action — not tied to a specific violation on record
May 18, 2000State Other7 linked violations
May 18, 2000State Other6 linked violations
May 18, 2000State Othergeneral compliance action — not tied to a specific violation on record
May 18, 2000State Other41 linked violations
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other7 linked violations
May 18, 2000State Other1 linked violation
May 18, 2000State Other11 linked violations
May 18, 2000State Other13 linked violations
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Other5 linked violations
May 18, 2000State Other1 linked violation
May 18, 2000State Other1 linked violation
May 18, 2000State Othergeneral compliance action — not tied to a specific violation on record
May 18, 2000State Othergeneral compliance action — not tied to a specific violation on record
May 18, 2000State Other1 linked violation
May 18, 2000State Othergeneral compliance action — not tied to a specific violation on record
May 18, 2000State Other1 linked violation
May 18, 2000State Othergeneral compliance action — not tied to a specific violation on record
May 18, 2000State Other7 linked violations
November 8, 1999State Other21 linked violations
July 6, 1999State Violation/Reminder Notice3 linked violations

Common questions

Is HIDDEN LAKE YELLOWSTONE COUNTY W AND S D required to publish a Consumer Confidence Report?: Yes. HIDDEN LAKE YELLOWSTONE COUNTY W AND S D is a community water system, and federal rules (40 CFR 141 Subpart O) require every community water system to publish a Consumer Confidence Report each year.
When is HIDDEN LAKE YELLOWSTONE COUNTY W AND S D’s next Consumer Confidence Report due?: HIDDEN LAKE YELLOWSTONE COUNTY W AND S D’s next Consumer Confidence Report is due by July 1, 2027. The report covers calendar year 2026.
Does HIDDEN LAKE YELLOWSTONE COUNTY W AND S D have any open drinking water violations on record?: As of August 1, 2026, EPA's federal records show no open violations for HIDDEN LAKE YELLOWSTONE COUNTY W AND S D.
What is a Consumer Confidence Report?: A Consumer Confidence Report (CCR) is the annual drinking water quality report that community water systems must provide to the people they serve. It lists the contaminants detected in the system’s water during the year, where the water comes from, and how the results compare with federal limits. EPA’s revised CCR rule takes effect January 1, 2027, and the first reports in the new format are due July 1, 2027.

Contact

FRANCO, KRISTINA

406-694-3868

BILLINGS, MT 59105