Water Quality in SIDNEY, MT (59270)

EPA violation data for public water systems serving ZIP code 59270.

223

Total Violations

Health-Based

188

Monitoring / Reporting

219

Resolved

What does this mean?

219 of 223 violations have been resolved. 35 are health-based violations, meaning contaminant levels exceeded federal safety limits. The remaining 188 are monitoring or reporting violations (missed testing deadlines or late paperwork — not necessarily a water quality issue). Not all violations mean your water is unsafe. The EPA requires reporting even for minor administrative issues.

Water systems: 28 Population served: 8,108

Violations Detail (223 total)

Contaminant	Category	MCL Limit	Measured	Date	Status	Health Effects
TTHM	Health-Based	N/A	0.115	Sep 30, 2025	Active	N/A
TTHM	Health-Based	N/A	0.115	Sep 30, 2025	Active	N/A
TTHM	Health-Based	N/A	0.115	Sep 30, 2025	Active	N/A
TTHM	Health-Based	N/A	0.108	Jun 30, 2025	Resolved	N/A
TTHM	Health-Based	N/A	0.108	Jun 30, 2025	Resolved	N/A
TTHM	Health-Based	N/A	0.108	Jun 30, 2025	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Mar 31, 2025	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Mar 31, 2025	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Mar 31, 2025	Resolved	N/A
TTHM	Health-Based	N/A	0.137	Mar 31, 2025	Resolved	N/A
TTHM	Health-Based	N/A	0.137	Mar 31, 2025	Resolved	N/A
TTHM	Health-Based	N/A	0.137	Mar 31, 2025	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Mar 31, 2025	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Mar 31, 2025	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Mar 31, 2025	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Jan 31, 2025	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Jan 31, 2025	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Jan 31, 2025	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Dec 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Dec 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Dec 31, 2024	Resolved	N/A
TTHM	Health-Based	N/A	0.1	Dec 31, 2024	Resolved	N/A
TTHM	Health-Based	N/A	0.1	Dec 31, 2024	Resolved	N/A
TTHM	Health-Based	N/A	0.1	Dec 31, 2024	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Dec 29, 2024	Active	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Dec 29, 2024	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Dec 29, 2024	Resolved	N/A
E. COLI	Monitoring	0	N/A	Dec 18, 2024	Resolved	Severe gastrointestinal illness; may be fatal in vulnerable populations
E. COLI	Monitoring	0	N/A	Dec 18, 2024	Resolved	Severe gastrointestinal illness; may be fatal in vulnerable populations
E. COLI	Monitoring	0	N/A	Dec 18, 2024	Resolved	Severe gastrointestinal illness; may be fatal in vulnerable populations
TTHM	Health-Based	N/A	105	Sep 30, 2024	Resolved	N/A
TTHM	Health-Based	N/A	105	Sep 30, 2024	Resolved	N/A
TTHM	Health-Based	N/A	105	Sep 30, 2024	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Sep 30, 2024	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Sep 30, 2024	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Sep 30, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Aug 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Aug 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Aug 31, 2024	Resolved	N/A
E. COLI	Monitoring	0	N/A	Aug 26, 2024	Resolved	Severe gastrointestinal illness; may be fatal in vulnerable populations
E. COLI	Monitoring	0	N/A	Aug 26, 2024	Resolved	Severe gastrointestinal illness; may be fatal in vulnerable populations
E. COLI	Monitoring	0	N/A	Aug 26, 2024	Resolved	Severe gastrointestinal illness; may be fatal in vulnerable populations
TTHM	Health-Based	N/A	110	Jun 30, 2024	Resolved	N/A
TTHM	Health-Based	N/A	110	Jun 30, 2024	Resolved	N/A
Consumer Confidence Rule	Monitoring	N/A	N/A	Jun 30, 2024	Resolved	N/A
Consumer Confidence Rule	Monitoring	N/A	N/A	Jun 30, 2024	Resolved	N/A
TTHM	Health-Based	N/A	110	Jun 30, 2024	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Jun 30, 2024	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Jun 30, 2024	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Jun 30, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	May 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	May 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	May 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	May 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	May 31, 2024	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	May 31, 2024	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	May 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Apr 30, 2024	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Apr 30, 2024	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Apr 30, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Apr 30, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Mar 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Mar 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Mar 31, 2024	Resolved	N/A
TTHM	Health-Based	N/A	0.115	Mar 31, 2024	Resolved	N/A
TTHM	Health-Based	N/A	0.115	Mar 31, 2024	Resolved	N/A
TTHM	Health-Based	N/A	0.115	Mar 31, 2024	Resolved	N/A
TTHM	Health-Based	N/A	0.115	Mar 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Mar 31, 2024	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Mar 31, 2024	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Mar 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Feb 29, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Feb 29, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Feb 29, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Feb 29, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Feb 29, 2024	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Feb 29, 2024	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Feb 29, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Feb 29, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Jan 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Jan 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Jan 31, 2024	Resolved	N/A
Revised Total Coliform Rule	Health-Based	N/A	N/A	Jan 12, 2024	Resolved	N/A
Revised Total Coliform Rule	Health-Based	N/A	N/A	Jan 12, 2024	Resolved	N/A
TTHM	Health-Based	N/A	0.141	Dec 31, 2023	Resolved	N/A
TTHM	Health-Based	N/A	0.141	Dec 31, 2023	Resolved	N/A
TTHM	Health-Based	N/A	0.141	Dec 31, 2023	Resolved	N/A
TTHM	Health-Based	N/A	0.141	Dec 31, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Dec 31, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Dec 31, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Dec 31, 2023	Resolved	N/A
Bromate	Monitoring	N/A	N/A	Dec 31, 2023	Resolved	Increased risk of cancer
Bromate	Monitoring	N/A	N/A	Dec 31, 2023	Resolved	Increased risk of cancer
Bromate	Monitoring	N/A	N/A	Dec 31, 2023	Resolved	Increased risk of cancer
Groundwater Rule	Monitoring	N/A	N/A	Nov 30, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Nov 30, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Nov 30, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Nov 30, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Nov 30, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Nov 30, 2023	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Nov 28, 2023	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Nov 28, 2023	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Nov 28, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Oct 31, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Oct 31, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Oct 31, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Oct 31, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Oct 31, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Oct 31, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 30, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 30, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 30, 2023	Resolved	N/A
TTHM	Health-Based	N/A	0.139	Sep 30, 2023	Resolved	N/A
TTHM	Health-Based	N/A	0.139	Sep 30, 2023	Resolved	N/A
TTHM	Health-Based	N/A	0.139	Sep 30, 2023	Resolved	N/A
TTHM	Health-Based	N/A	0.139	Sep 30, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Sep 30, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Sep 30, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Sep 30, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Aug 31, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Aug 31, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Aug 31, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Aug 31, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Aug 31, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Aug 31, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Jul 31, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Jul 31, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Jul 31, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Jun 30, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Jun 30, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Jun 30, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Jun 30, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Jun 30, 2023	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Jun 30, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Mar 31, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Mar 31, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Mar 31, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Mar 31, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Mar 31, 2023	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Mar 31, 2023	Resolved	N/A
Groundwater Rule	Health-Based	N/A	N/A	Feb 28, 2023	Resolved	N/A
Groundwater Rule	Health-Based	N/A	N/A	Feb 28, 2023	Resolved	N/A
Groundwater Rule	Health-Based	N/A	N/A	Feb 28, 2023	Resolved	N/A
Nitrate-Nitrite	Monitoring	N/A	N/A	Dec 31, 2022	Resolved	N/A
Nitrate-Nitrite	Monitoring	N/A	N/A	Dec 31, 2022	Resolved	N/A
Nitrate-Nitrite	Monitoring	N/A	N/A	Dec 31, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Dec 31, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Dec 31, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Dec 31, 2022	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Nov 30, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Nov 30, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Nov 30, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Nov 30, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Nov 30, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Nov 30, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Nov 30, 2022	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Nov 30, 2022	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Nov 30, 2022	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Nov 30, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Oct 31, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Oct 31, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Oct 31, 2022	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 30, 2022	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 30, 2022	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 30, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Sep 30, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Sep 30, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Sep 30, 2022	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Jul 31, 2022	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Jul 31, 2022	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Jul 31, 2022	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Jul 31, 2022	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Jun 30, 2022	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Jun 30, 2022	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Jun 30, 2022	Resolved	N/A
Bromate	Monitoring	N/A	N/A	Jun 30, 2022	Resolved	Increased risk of cancer
Bromate	Monitoring	N/A	N/A	Jun 30, 2022	Resolved	Increased risk of cancer
Bromate	Monitoring	N/A	N/A	Jun 30, 2022	Resolved	Increased risk of cancer
Groundwater Rule	Monitoring	N/A	N/A	Mar 31, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Mar 31, 2022	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	Mar 31, 2022	Resolved	N/A
Nitrate-Nitrite	Monitoring	N/A	N/A	Dec 31, 2021	Resolved	N/A
Nitrate-Nitrite	Monitoring	N/A	N/A	Dec 31, 2021	Resolved	N/A
Nitrate-Nitrite	Monitoring	N/A	N/A	Dec 31, 2021	Resolved	N/A
Bromate	Monitoring	N/A	N/A	Dec 31, 2021	Resolved	Increased risk of cancer
Bromate	Monitoring	N/A	N/A	Dec 31, 2021	Resolved	Increased risk of cancer
Bromate	Monitoring	N/A	N/A	Dec 31, 2021	Resolved	Increased risk of cancer
Lead and Copper Rule	Monitoring	N/A	N/A	Dec 29, 2021	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Dec 29, 2021	Resolved	N/A
E. COLI	Monitoring	0	N/A	Dec 23, 2021	Resolved	Severe gastrointestinal illness; may be fatal in vulnerable populations
E. COLI	Monitoring	0	N/A	Dec 23, 2021	Resolved	Severe gastrointestinal illness; may be fatal in vulnerable populations
E. COLI	Monitoring	0	N/A	Dec 23, 2021	Resolved	Severe gastrointestinal illness; may be fatal in vulnerable populations
E. COLI	Monitoring	0	N/A	Dec 23, 2021	Resolved	Severe gastrointestinal illness; may be fatal in vulnerable populations
E. COLI	Monitoring	0	N/A	Nov 10, 2021	Resolved	Severe gastrointestinal illness; may be fatal in vulnerable populations
E. COLI	Monitoring	0	N/A	Nov 10, 2021	Resolved	Severe gastrointestinal illness; may be fatal in vulnerable populations
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 30, 2021	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 30, 2021	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 30, 2021	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 30, 2021	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Sep 30, 2021	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Sep 30, 2021	Resolved	N/A
Lead and Copper Rule	Monitoring	N/A	N/A	Sep 30, 2021	Resolved	N/A
Consumer Confidence Rule	Monitoring	N/A	N/A	Sep 30, 2021	Resolved	N/A
Consumer Confidence Rule	Monitoring	N/A	N/A	Sep 30, 2021	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 30, 2021	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 30, 2021	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 30, 2021	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 1, 2021	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 1, 2021	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Sep 1, 2021	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Aug 31, 2021	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Aug 31, 2021	Resolved	N/A
Revised Total Coliform Rule	Monitoring	N/A	N/A	Aug 31, 2021	Resolved	N/A
Consumer Confidence Rule	Monitoring	N/A	N/A	Jun 30, 2021	Resolved	N/A
Consumer Confidence Rule	Monitoring	N/A	N/A	Jun 30, 2021	Resolved	N/A
Bromate	Monitoring	N/A	N/A	Jun 30, 2021	Resolved	Increased risk of cancer
Bromate	Monitoring	N/A	N/A	Jun 30, 2021	Resolved	Increased risk of cancer
Bromate	Monitoring	N/A	N/A	Jun 30, 2021	Resolved	Increased risk of cancer
Consumer Confidence Rule	Monitoring	N/A	N/A	Jun 30, 2021	Resolved	N/A
Consumer Confidence Rule	Monitoring	N/A	N/A	Jun 30, 2021	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	May 31, 2021	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	May 31, 2021	Resolved	N/A
Groundwater Rule	Monitoring	N/A	N/A	May 31, 2021	Resolved	N/A

Lead & Copper Levels

Violation Timeline

2025(18)

TTHM

Sep 30Active

TTHM

Sep 30Active

TTHM

Sep 30Active

TTHM

Jun 30Resolved

TTHM

Jun 30Resolved

TTHM

Jun 30Resolved

Revised Total Coliform Rule

Mar 31Resolved

Revised Total Coliform Rule

Mar 31Resolved

Revised Total Coliform Rule

Mar 31Resolved

TTHM

Mar 31Resolved

TTHM

Mar 31Resolved

TTHM

Mar 31Resolved

Lead and Copper Rule

Mar 31Resolved

Lead and Copper Rule

Mar 31Resolved

Lead and Copper Rule

Mar 31Resolved

Revised Total Coliform Rule

Jan 31Resolved

Revised Total Coliform Rule

Jan 31Resolved

Revised Total Coliform Rule

Jan 31Resolved

2024(66)

Revised Total Coliform Rule

Dec 31Resolved

Revised Total Coliform Rule

Dec 31Resolved

Revised Total Coliform Rule

Dec 31Resolved

TTHM

Dec 31Resolved

TTHM

Dec 31Resolved

TTHM

Dec 31Resolved

Lead and Copper Rule

Dec 29Active

Lead and Copper Rule

Dec 29Resolved

Lead and Copper Rule

Dec 29Resolved

E. COLI

Dec 18Resolved

E. COLI

Dec 18Resolved

E. COLI

Dec 18Resolved

TTHM

Sep 30Resolved

TTHM

Sep 30Resolved

TTHM

Sep 30Resolved

Lead and Copper Rule

Sep 30Resolved

Lead and Copper Rule

Sep 30Resolved

Lead and Copper Rule

Sep 30Resolved

Revised Total Coliform Rule

Aug 31Resolved

Revised Total Coliform Rule

Aug 31Resolved

Revised Total Coliform Rule

Aug 31Resolved

E. COLI

Aug 26Resolved

E. COLI

Aug 26Resolved

E. COLI

Aug 26Resolved

TTHM

Jun 30Resolved

TTHM

Jun 30Resolved

Consumer Confidence Rule

Jun 30Resolved

Consumer Confidence Rule

Jun 30Resolved

TTHM

Jun 30Resolved

Lead and Copper Rule

Jun 30Resolved

Lead and Copper Rule

Jun 30Resolved

Lead and Copper Rule

Jun 30Resolved

Revised Total Coliform Rule

May 31Resolved

Revised Total Coliform Rule

May 31Resolved

Revised Total Coliform Rule

May 31Resolved

Revised Total Coliform Rule

May 31Resolved

Revised Total Coliform Rule

May 31Resolved

Groundwater Rule

May 31Resolved

Groundwater Rule

May 31Resolved

Revised Total Coliform Rule

Apr 30Resolved

Groundwater Rule

Apr 30Resolved

Groundwater Rule

Apr 30Resolved

Revised Total Coliform Rule

Apr 30Resolved

Revised Total Coliform Rule

Mar 31Resolved

Revised Total Coliform Rule

Mar 31Resolved

Revised Total Coliform Rule

Mar 31Resolved

TTHM

Mar 31Resolved

TTHM

Mar 31Resolved

TTHM

Mar 31Resolved

TTHM

Mar 31Resolved

Revised Total Coliform Rule

Mar 31Resolved

Groundwater Rule

Mar 31Resolved

Groundwater Rule

Mar 31Resolved

Revised Total Coliform Rule

Feb 29Resolved

Revised Total Coliform Rule

Feb 29Resolved

Revised Total Coliform Rule

Feb 29Resolved

Revised Total Coliform Rule

Feb 29Resolved

Revised Total Coliform Rule

Feb 29Resolved

Groundwater Rule

Feb 29Resolved

Groundwater Rule

Feb 29Resolved

Revised Total Coliform Rule

Feb 29Resolved

Revised Total Coliform Rule

Jan 31Resolved

Revised Total Coliform Rule

Jan 31Resolved

Revised Total Coliform Rule

Jan 31Resolved

Revised Total Coliform Rule

Jan 12Resolved

Revised Total Coliform Rule

Jan 12Resolved

2023(59)

TTHM

Dec 31Resolved

TTHM

Dec 31Resolved

TTHM

Dec 31Resolved

TTHM

Dec 31Resolved

Revised Total Coliform Rule

Dec 31Resolved

Revised Total Coliform Rule

Dec 31Resolved

Revised Total Coliform Rule

Dec 31Resolved

Bromate

Dec 31Resolved

Bromate

Dec 31Resolved

Bromate

Dec 31Resolved

Groundwater Rule

Nov 30Resolved

Groundwater Rule

Nov 30Resolved

Groundwater Rule

Nov 30Resolved

Revised Total Coliform Rule

Nov 30Resolved

Revised Total Coliform Rule

Nov 30Resolved

Revised Total Coliform Rule

Nov 30Resolved

Lead and Copper Rule

Nov 28Resolved

Lead and Copper Rule

Nov 28Resolved

Lead and Copper Rule

Nov 28Resolved

Revised Total Coliform Rule

Oct 31Resolved

Revised Total Coliform Rule

Oct 31Resolved

Revised Total Coliform Rule

Oct 31Resolved

Groundwater Rule

Oct 31Resolved

Groundwater Rule

Oct 31Resolved

Groundwater Rule

Oct 31Resolved

Revised Total Coliform Rule

Sep 30Resolved

Revised Total Coliform Rule

Sep 30Resolved

Revised Total Coliform Rule

Sep 30Resolved

TTHM

Sep 30Resolved

TTHM

Sep 30Resolved

TTHM

Sep 30Resolved

TTHM

Sep 30Resolved

Groundwater Rule

Sep 30Resolved

Groundwater Rule

Sep 30Resolved

Groundwater Rule

Sep 30Resolved

Groundwater Rule

Aug 31Resolved

Revised Total Coliform Rule

Aug 31Resolved

Revised Total Coliform Rule

Aug 31Resolved

Revised Total Coliform Rule

Aug 31Resolved

Groundwater Rule

Aug 31Resolved

Groundwater Rule

Aug 31Resolved

Groundwater Rule

Jul 31Resolved

Groundwater Rule

Jul 31Resolved

Groundwater Rule

Jul 31Resolved

Groundwater Rule

Jun 30Resolved

Revised Total Coliform Rule

Jun 30Resolved

Groundwater Rule

Jun 30Resolved

Revised Total Coliform Rule

Jun 30Resolved

Revised Total Coliform Rule

Jun 30Resolved

Groundwater Rule

Jun 30Resolved

Revised Total Coliform Rule

Mar 31Resolved

Revised Total Coliform Rule

Mar 31Resolved

Revised Total Coliform Rule

Mar 31Resolved

Revised Total Coliform Rule

Mar 31Resolved

Revised Total Coliform Rule

Mar 31Resolved

Revised Total Coliform Rule

Mar 31Resolved

Groundwater Rule

Feb 28Resolved

Groundwater Rule

Feb 28Resolved

Groundwater Rule

Feb 28Resolved

How Does This Compare?

SIDNEY (59270) has 223 recorded violations, including 35 health-based. 4 remain unresolved. Consider testing your tap water independently for added peace of mind.

Recommended Water Filters

Based on the contaminants detected in your area, these filter types may help improve your water quality.

Reverse Osmosis System

Highly effective at removing heavy metals, dissolved solids, and a wide range of contaminants. Recommended for homes with lead or arsenic concerns.

Targets:Lead, Copper, Arsenic, Mercury, Cadmium

Look for:NSF/ANSI 58 certified

NSF Certified Products → EPA Safe Drinking Water Guide →

Activated Carbon Filter

Excellent for removing chlorine, chloramine, and disinfection byproducts like THMs and HAAs. Available as pitcher filters, countertop, or under-sink units.

Targets:THMs, HAAs, Chlorine, Chloramine, Taste & Odor

Look for:NSF/ANSI 42 & 53 certified

NSF Certified Products → EPA Safe Drinking Water Guide →

UV Water Purifier

Uses ultraviolet light to neutralize bacteria, viruses, and parasites without chemicals. Ideal for homes with microbial contamination concerns.

Targets:E. coli, Coliform, Giardia, Cryptosporidium

Look for:NSF/ANSI 55 (Class A) certified

NSF Certified Products → EPA Safe Drinking Water Guide →

Always look for filters certified by NSF International for the specific contaminants you want to remove.

Water Quality in SIDNEY, MT (59270)

What does this mean?

Violations Detail (223 total)

Lead & Copper Levels

Violation Timeline

2025(18)

2024(66)

2023(59)

2022(38)

2021(42)

How Does This Compare?

Recommended Water Filters

Reverse Osmosis System

Activated Carbon Filter

UV Water Purifier

Nearby ZIP Codes

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