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Helena Water System

Published drinking-water records and contacts for Helena Water System. System MT0000241. Review sources and dates; not a real-time water assessment.

System ID
MT0000241
State or territory
MT
Published population served
32091
System type (source code)
CWS

Published records and dates

Missing records here do not mean the provider did not test. Published records are not a real-time assessment of your tap water.

Published testing results

Selected recent records are shown below. Different sampling locations and dates are not interchangeable. These excerpts are not a complete testing history.

“<” means below the stated reporting limit, not zero. A reported measurement alone is not a safety verdict. Read an example

EPA UCMR 5 — most recent imported sample per substance
SubstancePublished resultReporting limitSample dateSampling location
11Cl-PF3OUdS< 0.005 µg/L0.005 µg/L2024-06-13Ten Mile SWTP Intake / EP504
4:2 FTS< 0.003 µg/L0.003 µg/L2024-06-13Missouri WTP / EP502
6:2 FTS< 0.005 µg/L0.005 µg/L2024-06-13Ten Mile SWTP Intake / EP504
8:2 FTS< 0.005 µg/L0.005 µg/L2024-06-13Ten Mile SWTP Intake / EP504
9Cl-PF3ONS< 0.002 µg/L0.002 µg/L2024-06-13Ten Mile SWTP Intake / EP504
ADONA< 0.003 µg/L0.003 µg/L2024-06-13Missouri WTP / EP502
HFPO-DA< 0.005 µg/L0.005 µg/L2024-06-13Ten Mile SWTP Intake / EP504
NEtFOSAA< 0.005 µg/L0.005 µg/L2024-05-08Missouri WTP / EP502
NFDHA< 0.02 µg/L0.02 µg/L2024-06-13Ten Mile SWTP Intake / EP504
NMeFOSAA< 0.006 µg/L0.006 µg/L2024-05-08Ten Mile SWTP Intake / EP504
PFBA< 0.005 µg/L0.005 µg/L2024-06-13Missouri WTP / EP502
PFBS< 0.003 µg/L0.003 µg/L2024-06-13Ten Mile SWTP Intake / EP504
PFDA< 0.003 µg/L0.003 µg/L2024-06-13Missouri WTP / EP502
PFDoA< 0.003 µg/L0.003 µg/L2024-06-13Ten Mile SWTP Intake / EP504
PFEESA< 0.003 µg/L0.003 µg/L2024-06-13Ten Mile SWTP Intake / EP504
PFHpA< 0.003 µg/L0.003 µg/L2024-06-13Ten Mile SWTP Intake / EP504
PFHpS< 0.003 µg/L0.003 µg/L2024-06-13Ten Mile SWTP Intake / EP504
PFHxA< 0.003 µg/L0.003 µg/L2024-06-13Missouri WTP / EP502
PFHxS< 0.003 µg/L0.003 µg/L2024-06-13Missouri WTP / EP502
PFMBA< 0.003 µg/L0.003 µg/L2024-06-13Ten Mile SWTP Intake / EP504
PFMPA< 0.004 µg/L0.004 µg/L2024-06-13Missouri WTP / EP502
PFNA< 0.004 µg/L0.004 µg/L2024-06-13Ten Mile SWTP Intake / EP504
PFOA< 0.004 µg/L0.004 µg/L2024-06-13Missouri WTP / EP502
PFOS< 0.004 µg/L0.004 µg/L2024-06-13Missouri WTP / EP502
PFPeA< 0.003 µg/L0.003 µg/L2024-06-13Missouri WTP / EP502
PFPeS< 0.004 µg/L0.004 µg/L2024-06-13Missouri WTP / EP502
PFTA< 0.008 µg/L0.008 µg/L2024-05-08Ten Mile SWTP Intake / EP504
PFTrDA< 0.007 µg/L0.007 µg/L2024-05-08Ten Mile SWTP Intake / EP504
PFUnA< 0.002 µg/L0.002 µg/L2024-06-13Ten Mile SWTP Intake / EP504
lithium62 µg/L9 µg/L2024-05-08Missouri WTP / EP502

Download all EPA UCMR 5 records (CSV)

Lead and copper: 90th-percentile summaries

These describe a monitoring period across sampled locations, not the result at your home. How to read the 90th percentile

Eight most recent imported monitoring summaries
SubstancePublished 90th percentileMonitoring periodSource quarter
Lead (PB90) 0.003 mg/L2022-01-01 – 2024-12-312026Q3
Lead (PB90) 0.003 mg/L2019-01-01 – 2021-12-312026Q3
Lead (PB90) 0.001 mg/L2016-01-01 – 2018-12-312026Q3
Lead (PB90) 0.004 mg/L2013-01-01 – 2015-12-312026Q3
Lead (PB90) 0.004 mg/L2011-01-01 – 2013-12-312026Q3
Lead (PB90) 0.004 mg/L2008-01-01 – 2010-12-312026Q3
Lead (PB90) 0.004 mg/L2005-01-01 – 2007-12-312026Q3
Lead (PB90) 0.006 mg/L2002-01-01 – 2004-12-312026Q3
Twelve most recent imported state laboratory records
SubstancePublished resultSample dateLocation / source
NITRATE-NITRITE1.36 mg/L2026-08-13EP505 / Montana selected chemical sample panels
NITRATE-NITRITE0.04 mg/L2026-07-15EP504 / Montana selected chemical sample panels
ARSENIC0.003 mg/L2026-07-15EP504 / Montana selected chemical sample panels
NITRATE-NITRITE0.04 mg/L2026-07-15EP502 / Montana selected chemical sample panels
ARSENIC0.007 mg/L2026-05-13EP502 / Montana selected chemical sample panels

State sampling points can include untreated water. Publisher qualifiers and units are retained; consult the full source notes before interpreting a record.

Download state records with source notes (CSV)

Published compliance history

4 imported records. Status is as recorded in the source; historical records are not current advisories. Missing records do not establish that no violations occurred.

Twenty most recent imported compliance records
Rule / recordPeriodRecorded statusHealth-based (EPA classification)Source quarter
Stage 2 Disinfectants and Disinfection Byproducts Rule / Maximum Contaminant Level Violation, Average2023-01-01 – 2023-03-31ResolvedYes2026Q3
Stage 2 Disinfectants and Disinfection Byproducts Rule / Maximum Contaminant Level Violation, Average2022-10-01 – 2022-12-31ResolvedYes2026Q3
Stage 2 Disinfectants and Disinfection Byproducts Rule / Maximum Contaminant Level Violation, Average2022-07-01 – 2022-09-30ResolvedYes2026Q3
Radionuclides and Revised Rad Rule / Monitoring, Regular2008-01-01 – 2016-12-31ArchivedNo2026Q3

Source dates and refresh checks

A refresh check is not a sample date. Publication periods, sample dates and checks are shown separately.

Administrative contact (EPA filing)

Sanderson, Janice R: 406-457-8512

An administrative filing contact may not be a customer-service line. Confirm current contact details with the provider.

Official state resources · How to read these records