What was found in Missoula's water
The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate-Nitrite | 1730 µg/L 17% of the EPA limit 10000 µg/L Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 3940 µg/L — WESTVIEW MOBILE HOME PARK · 947 people · 2019 | 61/65 | SYR4 |
| Copper | 318 µg/L 24% of the EPA limit 1300 µg/L Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 2437 µg/L — SPRING MEADOWS COUNTY WATER DISTRICT · 162 people · 2019 | 62/65 | SYR4 |
| Nitrate | 2220 µg/L 22% of the EPA limit 10000 µg/L Highest in the city: GOODAN KEIL CO WATER DIST · 207 people · 2017 | 25/65 | SYR4 |
| Fluoride | 200 µg/L 5% of the EPA limit 4000 µg/L Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 1070 µg/L — BITTERROOT MEADOWS HOA LOLO · 120 people · 2019 | 48/65 | SYR4 |
| Barium | 456 µg/L 23% of the EPA limit 2000 µg/L Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 718 µg/L — COUNTRYSIDE COURT MISSOULA · 37 people · 2017 | 57/65 | SYR4 |
| Lead | 5 µg/L 33% of the EPA limit 15 µg/L Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 135.7 µg/L — EAST VIEW ACRES WATER SYSTEM · 25 people · 2019 | 57/65 | SYR4 |
| Chromium | 36 µg/L 36% of the EPA limit 100 µg/L Highest in the city: WESTVIEW MOBILE HOME PARK · 947 people · 2019 | 3/65 | SYR4 |
| TTHM | 9.7 µg/L 12% of the EPA limit 80 µg/L Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 21.75 µg/L — PHANTOM HILLS WATER SYSTEM · 810 people · 2019 | 9/65 | SYR4 |
| Lithium | 15 µg/L No EPA limit set Main supplier: MISSOULA WATER · 68,200 people · 2025 | 1/65 | UCMR-5 |
| Nitrite | 10 µg/L 1% of the EPA limit 1000 µg/L Main supplier: MISSOULA WATER · 68,200 people · 2019 | 1/65 | SYR4 |
| Gross Beta Particle Activity | 9.74 pCi/L No EPA limit set Main supplier: MISSOULA WATER · 68,200 people · 2018 | 3/65 | SYR4 |
| Arsenic | 3 µg/L 30% of the EPA limit 10 µg/L Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 8.9 µg/L — NEW CASTLE COURT · 55 people · 2017 | 29/65 | SYR4 |
| Chloroform | 1.137 µg/L No EPA limit set Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 8.63 µg/L — PHANTOM HILLS WATER SYSTEM · 810 people · 2019 | 8/65 | SYR4 |
| Gross Alpha, Excl. Radon And U | 4.99 pCi/L 33% of the EPA limit 15 pCi/L Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 7.3 pCi/L — BUENA VISTA COMMUNITY, INC · 90 people · 2016 | 37/65 | SYR4 |
| Bromodichloromethane | 2.2 µg/L No EPA limit set Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 5.92 µg/L — PHANTOM HILLS WATER SYSTEM · 810 people · 2019 | 5/65 | SYR4 |
| Bromoform | 2.5 µg/L No EPA limit set Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 5.625 µg/L — TRAVOIS VILLAGE MOBILE PARK · 702 people · 2019 | 7/65 | SYR4 |
| Dibromochloromethane | 3.7 µg/L No EPA limit set Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 4.65 µg/L — PHANTOM HILLS WATER SYSTEM · 810 people · 2019 | 4/65 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 4.6 µg/L 77% of the EPA limit 6 µg/L Main supplier: MISSOULA WATER · 68,200 people · 2019 | 3/65 | SYR4 |
| Total Haloacetic Acids (HAA5) | 1.085 µg/L 1.8% of the EPA limit 60 µg/L Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 4.4 µg/L — TRAVOIS VILLAGE MOBILE PARK · 702 people · 2019 | 6/65 | SYR4 |
| Combined Uranium | 2 µg/L 6.7% of the EPA limit 30 µg/L Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 4 µg/L — GOODAN KEIL CO WATER DIST · 207 people · 2016 | 39/65 | SYR4 |
| Combined Radium (-226 And -228) | 2.635 pCi/L 53% of the EPA limit 5 pCi/L Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 3.785 pCi/L — MOBILE CITY TRAILER COURT · 175 people · 2016 | 29/65 | SYR4 |
| Selenium | 1 µg/L 2% of the EPA limit 50 µg/L Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 2.95 µg/L — SPRING MEADOWS COUNTY WATER DISTRICT · 162 people · 2017 | 4/65 | SYR4 |
| Dichloroacetic Acid | 2.2955 µg/L No EPA limit set Highest in the city: TRAVOIS VILLAGE MOBILE PARK · 702 people · 2019 | 2/65 | SYR4 |
| Dibromoacetic Acid | 1.085 µg/L No EPA limit set Main supplier: MISSOULA WATER · 68,200 people · 2019
Highest in the city: 2.04 µg/L — TRAVOIS VILLAGE MOBILE PARK · 702 people · 2019 | 5/65 | SYR4 |
| Antimony, Total | 2 µg/L 33% of the EPA limit 6 µg/L Highest in the city: WESTVIEW MOBILE HOME PARK · 947 people · 2019 | 1/65 | SYR4 |
| Dichloromethane | 1.9 µg/L 38% of the EPA limit 5 µg/L Main supplier: MISSOULA WATER · 68,200 people · 2019 | 2/65 | SYR4 |
| Monobromoacetic Acid | 0.7220 µg/L No EPA limit set Highest in the city: TRAVOIS VILLAGE MOBILE PARK · 702 people · 2019 | 1/65 | SYR4 |
| Tetrachloroethylene | 0.2600 µg/L 5.2% of the EPA limit 5 µg/L Main supplier: MISSOULA WATER · 68,200 people · 2019 | 1/65 | SYR4 |
| Trichloroacetic Acid | 0.1755 µg/L No EPA limit set Highest in the city: TRAVOIS VILLAGE MOBILE PARK · 702 people · 2019 | 1/65 | SYR4 |
| Lead | 0.0010 mg/L 6.7% of the EPA limit 0.0150 mg/L Main supplier: MISSOULA WATER · 68,200 people · 2026
Highest in the city: 0.0110 mg/L — MISSOULA VILLAGE WEST TR CT · 68 people · 2019 | 65/65 | LCR |
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 the
system's samples — over 100% is worth reading, but is not by itself a
violation.
Formal violations are listed separately.
These are the utilities' own EPA-reported results, not a city-wide
average. A detection means the lab measured the
substance — it isn't the same as exceeding a legal limit. Hover a source
tag to see the EPA program and years behind each figure.
Water suppliers serving Missoula
The 50 largest of 65 suppliers serving Missoula, by population served.
Frequently asked questions about Missoula tap water
Is Missoula tap water safe to drink?
EPA testing detected 30 contaminants in the water serving Missoula. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.
How many water suppliers serve Missoula?
65 public water suppliers report drinking-water monitoring for Missoula, Montana to the EPA. Each is listed above with its population served.
What contaminants are in Missoula's water?
The contaminants EPA monitoring detected in Missoula include Nitrate-Nitrite, Copper, Nitrate, Fluoride, Barium. The full list, with the level at the main supplier and the data source, is in the table above.
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.