What was found in Hermiston'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 | 6600 µg/L 66% of the EPA limit 10000 µg/L Main supplier: HERMISTON, CITY OF · 20,000 people · 2019
Highest in the city: 12700 µg/L — HAT ROCK WATER COMPANY · 150 people · 2019 | 6/7 | SYR4 |
| Nitrate-Nitrite | 5560 µg/L 56% of the EPA limit 10000 µg/L Highest in the city: VISTA HOME PARK · 300 people · 2013 | 3/7 | SYR4 |
| Fluoride | 2554.5 µg/L 64% of the EPA limit 4000 µg/L Highest in the city: NORTH HILL WATER CORPORATION · 100 people · 2018 | 5/7 | SYR4 |
| Copper | 296.15 µg/L 23% of the EPA limit 1300 µg/L Main supplier: HERMISTON, CITY OF · 20,000 people · 2017
Highest in the city: 984.5 µg/L — HAT ROCK WATER COMPANY · 150 people · 2018 | 5/7 | SYR4 |
| Nitrite | 120 µg/L 12% of the EPA limit 1000 µg/L Highest in the city: SHADY REST MOBILE COURT · 110 people · 2019 | 2/7 | SYR4 |
| Barium | 106.8 µg/L 5.3% of the EPA limit 2000 µg/L Highest in the city: CHARLES TRACTS WATER COMPANY · 290 people · 2019 | 3/7 | SYR4 |
| Total Haloacetic Acids (HAA5) | 49.525 µg/L 83% of the EPA limit 60 µg/L Main supplier: HERMISTON, CITY OF · 20,000 people · 2019 | 2/7 | SYR4 |
| TTHM | 46.97 µg/L 59% of the EPA limit 80 µg/L Main supplier: HERMISTON, CITY OF · 20,000 people · 2019 | 4/7 | SYR4 |
| Lithium | 32 µg/L No EPA limit set Main supplier: HERMISTON, CITY OF · 20,000 people · 2024 | 1/7 | UCMR-5 |
| Lead | 11.5 µg/L 77% of the EPA limit 15 µg/L Main supplier: HERMISTON, CITY OF · 20,000 people · 2017 | 5/7 | SYR4 |
| Gross Alpha, Excl. Radon And U | 7.2125 pCi/L 48% of the EPA limit 15 pCi/L Main supplier: HERMISTON, CITY OF · 20,000 people · 2018
Highest in the city: 11.157 pCi/L — VISTA HOME PARK · 300 people · 2019 | 5/7 | SYR4 |
| Arsenic | 9 µg/L 90% of the EPA limit 10 µg/L Main supplier: HERMISTON, CITY OF · 20,000 people · 2014 | 6/7 | SYR4 |
| Gross Beta Particle Activity | 7.3 pCi/L No EPA limit set Highest in the city: HAT ROCK WATER COMPANY · 150 people · 2017 | 1/7 | SYR4 |
| Combined Uranium | 7.286 µg/L 24% of the EPA limit 30 µg/L Main supplier: HERMISTON, CITY OF · 20,000 people · 2018 | 5/7 | SYR4 |
| Chromium | 2.76 µg/L 2.8% of the EPA limit 100 µg/L Highest in the city: VISTA HOME PARK · 300 people · 2013 | 2/7 | SYR4 |
| Combined Radium (-226 And -228) | 0.8998 pCi/L 18% of the EPA limit 5 pCi/L Highest in the city: VISTA HOME PARK · 300 people · 2019 | 1/7 | SYR4 |
| Xylenes, Total | 0.6600 µg/L 0% of the EPA limit 10000 µg/L Main supplier: HERMISTON, CITY OF · 20,000 people · 2019 | 1/7 | SYR4 |
| cis-1,2-Dichloroethylene | 0.5000 µg/L 0.7% of the EPA limit 70 µg/L Highest in the city: CHARLES TRACTS WATER COMPANY · 290 people · 2019 | 1/7 | SYR4 |
| PFHXS | 0.0120 µg/L No EPA limit set Main supplier: HERMISTON, CITY OF · 20,000 people · 2024 | 1/7 | UCMR-5 |
| PFOS | 0.0120 µg/L No EPA limit set Main supplier: HERMISTON, CITY OF · 20,000 people · 2024 | 1/7 | UCMR-5 |
| PFBS | 0.0100 µg/L No EPA limit set Main supplier: HERMISTON, CITY OF · 20,000 people · 2024 | 1/7 | UCMR-5 |
| Lead | 0.0030 mg/L 20% of the EPA limit 0.0150 mg/L Main supplier: HERMISTON, CITY OF · 20,000 people · 2023
Highest in the city: 0.0050 mg/L — VISTA HOME PARK · 300 people · 2024 | 7/7 | LCR |
| Pfpea | 0.0042 µg/L No EPA limit set Main supplier: HERMISTON, CITY OF · 20,000 people · 2024 | 1/7 | UCMR-5 |
| Pfhxa | 0.0039 µg/L No EPA limit set Main supplier: HERMISTON, CITY OF · 20,000 people · 2024 | 1/7 | UCMR-5 |
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 Hermiston
| Supplier | Population served |
|---|---|
| HERMISTON, CITY OF | 20,000 |
| VISTA HOME PARK | 300 |
| CHARLES TRACTS WATER COMPANY | 290 |
| HAT ROCK WATER COMPANY | 150 |
| CHART SUBDIVISION | 125 |
| SHADY REST MOBILE COURT | 110 |
| NORTH HILL WATER CORPORATION | 100 |
Frequently asked questions about Hermiston tap water
Is Hermiston tap water safe to drink?
EPA testing detected 24 contaminants in the water serving Hermiston. 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 Hermiston?
7 public water suppliers report drinking-water monitoring for Hermiston, Oregon to the EPA. Each is listed above with its population served.
What contaminants are in Hermiston's water?
The contaminants EPA monitoring detected in Hermiston include Nitrate, Nitrate-Nitrite, Fluoride, Copper, Nitrite. 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.