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Tap water quality report

Thompson Falls City of

EPA monitoring tested this supplier for 74 contaminants and detected 16. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

74
contaminants tested
16
detected
1,950
people served
3
health-based violations
Montana rankingsLead in MontanaPFAS in Montana
Water source
Ground water
Ownership
Local government
Counties served
Sanders

Compliance record

Formal violations the EPA has on file for this supplier. A health-based violation means a contaminant limit or a required treatment was breached; the rest are monitoring or reporting failures — still violations, but not a measured health risk.

3
health-based violations
35
violations on file
0
still open
ViolationTypeStatusPeriod
TT Health-based Resolved 1999-12-01 → 1999-12-31
TT Health-based Resolved 1999-12-01 → 1999-12-31
TT Health-based Resolved 1999-12-01 → 1999-12-31
Other Monitoring Resolved 2015-07-01
Other Monitoring Resolved 2015-07-01
MR Monitoring Resolved 2005-11-01 → 2005-11-30
MR Monitoring Resolved 2005-11-01 → 2005-11-30
MR Monitoring Resolved 2005-11-01 → 2005-11-30
MR Monitoring Resolved 1997-04-01 → 1997-04-30
MR Monitoring Resolved 1997-01-01 → 1997-01-31

Other contaminants detected

Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the 95th percentile of this system's samples — over 100% is worth reading, but is not by itself a violation. Where a single sample came in higher than that percentile, it is noted under the bar. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Copper
302 µg/L 23%
of the EPA limit 1300 µg/L
worst single sample: 410 µg/L
30/30 SYR4 2013–2019
Nitrate-Nitrite
515 µg/L 5.1%
of the EPA limit 10000 µg/L
worst single sample: 530 µg/L
16/16 SYR4 2012–2019
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 13/13 LCR 2025
TTHM
3.35 µg/L 4.2%
of the EPA limit 80 µg/L
worst single sample: 3.4 µg/L
11/20 SYR4 2012–2019
Chloroform
2.57 µg/L
No EPA limit set
worst single sample: 2.6 µg/L
7/20 SYR4 2012–2019
Lead
2 µg/L 13%
of the EPA limit 15 µg/L
 7/30 SYR4 2013–2019
Fluoride
67.5 µg/L 1.7%
of the EPA limit 4000 µg/L
worst single sample: 70 µg/L
6/6 SYR4 2012–2018
Nitrate
510 µg/L 5.1%
of the EPA limit 10000 µg/L
 6/6 SYR4 2012–2015
Total Haloacetic Acids (HAA5)
2.2 µg/L 3.7%
of the EPA limit 60 µg/L
worst single sample: 2.4 µg/L
6/13 SYR4 2013–2019
Dichloroacetic Acid
2.04 µg/L
No EPA limit set
worst single sample: 2.2 µg/L
5/13 SYR4 2013–2019
Arsenic
1.95 µg/L 20%
of the EPA limit 10 µg/L
worst single sample: 2 µg/L
2/6 SYR4 2012–2018
Bromodichloromethane
0.5955 µg/L
No EPA limit set
worst single sample: 0.6000 µg/L
2/20 SYR4 2012–2019
Combined Radium (-226 And -228)
1.8 pCi/L 36%
of the EPA limit 5 pCi/L
 1/2 SYR4 2015
Combined Uranium
1 µg/L 3.3%
of the EPA limit 30 µg/L
 1/2 SYR4 2015
Dibromoacetic Acid
0.3700 µg/L
No EPA limit set
 1/13 SYR4 2013–2019
Toluene
1.4 µg/L 0.1%
of the EPA limit 1000 µg/L
 1/7 SYR4 2012–2018
58 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-Dichloroethane1,2-Dichloropropane2,4,5-TP2,4-DAntimony, TotalAtrazineBhc-GammaBariumBenzeneBenzo(A)PyreneBeryllium, TotalBromoformChlorobenzeneCadmiumCarbofuranCarbon TetrachlorideChlordaneChromiumDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDibromochloromethaneDinosebEndrinEthylbenzeneGross Alpha, Excl. Radon And UHexachlorobenzeneHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorMonobromoacetic AcidMonochloroacetic AcidNitriteOxamylPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalToxapheneTrichloroacetic AcidTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
HARNETT, JONATHAN O
Phone
406-827-3557
Email
[email protected]

Frequently asked questions about Thompson Falls City of

Is Thompson Falls City of tap water safe to drink?

EPA monitoring detected 16 contaminants in Thompson Falls City of's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.

What contaminants were detected in Thompson Falls City of's water?

EPA monitoring detected Copper, Nitrate-Nitrite, Lead, TTHM, Chloroform, and others. The full list with the level and data source for each is above.

How many people does Thompson Falls City of serve?

Thompson Falls City of reports serving 1,950 people in Montana, per its EPA record.

Has Thompson Falls City of had any water quality violations?

The EPA has 35 violations on file for Thompson Falls City of, of which 3 are health-based (a contaminant limit or required treatment was breached) and 0 remain open. The rest are monitoring or reporting failures.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.