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Tap water quality report

Tri County Water District

EPA monitoring tested this supplier for 74 contaminants and detected 20. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

74
contaminants tested
20
detected
470
people served
0
health-based violations
Montana rankingsLead in MontanaPFAS in Montana
Water source
Ground water
Ownership
Local government
Counties served
Teton

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.

0
health-based violations
214
violations on file
0
still open
ViolationTypeStatusPeriod
MR Monitoring Resolved 2024-12-30
MR Monitoring Resolved 2024-12-30
Other Monitoring Resolved 2023-07-01
Other Monitoring Resolved 2023-07-01
MR Monitoring Resolved 2023-01-01 → 2025-12-31
MR Monitoring Resolved 2023-01-01 → 2025-12-31
MR Monitoring Resolved 2023-01-01 → 2025-12-31
MR Monitoring Resolved 2023-01-01 → 2025-12-31
MR Monitoring Resolved 2023-01-01 → 2025-12-31
MR Monitoring Resolved 2023-01-01 → 2025-12-31

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
Nitrate-Nitrite
5060 µg/L 51%
of the EPA limit 10000 µg/L
worst single sample: 5400 µg/L
46/46 SYR4 2012–2019
Lead
0.0010 mg/L 6.7%
of the EPA limit 0.0150 mg/L
 12/12 LCR 2024
Copper
764.9 µg/L 59%
of the EPA limit 1300 µg/L
worst single sample: 944 µg/L
10/10 SYR4 2014–2018
Combined Uranium
10 µg/L 33%
of the EPA limit 30 µg/L
 8/8 SYR4 2012–2019
Lead
6.25 µg/L 42%
of the EPA limit 15 µg/L
worst single sample: 8 µg/L
8/10 SYR4 2014–2018
Bromodichloromethane
5.18 µg/L
No EPA limit set
worst single sample: 5.24 µg/L
7/9 SYR4 2012–2019
Chloroform
15.45 µg/L
No EPA limit set
worst single sample: 16.9 µg/L
6/9 SYR4 2012–2019
Dibromochloromethane
2.7375 µg/L
No EPA limit set
worst single sample: 3.07 µg/L
6/9 SYR4 2012–2019
Dichloroacetic Acid
12.322 µg/L
No EPA limit set
worst single sample: 12.8 µg/L
3/3 SYR4 2013–2019
Gross Alpha, Excl. Radon And U
4.17 pCi/L 28%
of the EPA limit 15 pCi/L
worst single sample: 4.3 pCi/L
3/8 SYR4 2012–2019
Monochloroacetic Acid
5.9525 µg/L
No EPA limit set
worst single sample: 6.54 µg/L
3/3 SYR4 2013–2019
TTHM
23.48 µg/L 29%
of the EPA limit 80 µg/L
worst single sample: 23.9 µg/L
3/3 SYR4 2013–2019
Total Haloacetic Acids (HAA5)
20.79 µg/L 35%
of the EPA limit 60 µg/L
worst single sample: 21.5 µg/L
3/3 SYR4 2013–2019
Trichloroacetic Acid
4.991 µg/L
No EPA limit set
worst single sample: 5.18 µg/L
3/3 SYR4 2013–2019
Barium
76.95 µg/L 3.8%
of the EPA limit 2000 µg/L
worst single sample: 77 µg/L
2/2 SYR4 2016–2019
Bromoform
0.8250 µg/L
No EPA limit set
worst single sample: 0.8400 µg/L
2/9 SYR4 2012–2019
Combined Radium (-226 And -228)
1.435 pCi/L 29%
of the EPA limit 5 pCi/L
worst single sample: 1.5 pCi/L
2/7 SYR4 2012–2019
Dibromoacetic Acid
0.5618 µg/L
No EPA limit set
worst single sample: 0.5630 µg/L
2/3 SYR4 2013–2019
Fluoride
884.85 µg/L 22%
of the EPA limit 4000 µg/L
worst single sample: 887 µg/L
2/2 SYR4 2016–2019
Selenium
2.95 µg/L 5.9%
of the EPA limit 50 µg/L
worst single sample: 3 µg/L
2/2 SYR4 2016–2019
54 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, TotalArsenicAtrazineBhc-GammaBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCadmiumCarbofuranCarbon TetrachlorideChlordaneChromiumDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebEthylene DibromideEndrinEthylbenzeneHexachlorobenzeneHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorMonobromoacetic AcidOxamylPentachlorophenolPicloramSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
GRILLEY, CLIFTON H
Email
[email protected]

Frequently asked questions about Tri County Water District

Is Tri County Water District tap water safe to drink?

EPA monitoring detected 20 contaminants in Tri County Water District'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 Tri County Water District's water?

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

How many people does Tri County Water District serve?

Tri County Water District reports serving 470 people in Montana, per its EPA record.

Has Tri County Water District had any water quality violations?

The EPA has 214 violations on file for Tri County Water District, of which 0 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.