What was found in Oak View'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 | 320000 µg/L 3200% of the EPA limit, at the 95th percentile of samples — 10000 µg/L Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 1/2 | SYR4 |
| Nitrate | 12200 µg/L 122% of the EPA limit, at the 95th percentile of samples — 10000 µg/L Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 1/2 | SYR4 |
| Fluoride | 510 µg/L 13% of the EPA limit 4000 µg/L Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 1/2 | SYR4 |
| Barium | 130.4 µg/L 6.5% of the EPA limit 2000 µg/L Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 1/2 | SYR4 |
| TTHM | 64.65 µg/L 81% of the EPA limit 80 µg/L Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 2/2 | SYR4 |
| Total Haloacetic Acids (HAA5) | 58.9 µg/L 98% of the EPA limit 60 µg/L Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 2/2 | SYR4 |
| Chloroform | 41.13 µg/L No EPA limit set Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 2/2 | SYR4 |
| Lithium | 16 µg/L No EPA limit set Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2023
Highest in the city: 37 µg/L — OJAI WATER SYSTEM · 6,801 people · 2025 | 2/2 | UCMR-5 |
| Trichloroacetic Acid | 30.3 µg/L No EPA limit set Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 2/2 | SYR4 |
| Dichloroacetic Acid | 27 µg/L No EPA limit set Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 2/2 | SYR4 |
| Bromoform | 2 µg/L No EPA limit set Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019
Highest in the city: 21.45 µg/L — OJAI WATER SYSTEM · 6,801 people · 2019 | 2/2 | SYR4 |
| Dibromochloromethane | 6 µg/L No EPA limit set Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019
Highest in the city: 20.8 µg/L — OJAI WATER SYSTEM · 6,801 people · 2019 | 2/2 | SYR4 |
| Copper | 20 µg/L 1.5% of the EPA limit 1300 µg/L Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 1/2 | SYR4 |
| Bromodichloromethane | 18 µg/L No EPA limit set Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 2/2 | SYR4 |
| Monochloroacetic Acid | 3 µg/L No EPA limit set Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019
Highest in the city: 8.115 µg/L — OJAI WATER SYSTEM · 6,801 people · 2019 | 2/2 | SYR4 |
| Dibromoacetic Acid | 2 µg/L No EPA limit set Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019
Highest in the city: 6.37 µg/L — OJAI WATER SYSTEM · 6,801 people · 2019 | 2/2 | SYR4 |
| Monobromoacetic Acid | 4 µg/L No EPA limit set Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019
Highest in the city: 6.19 µg/L — OJAI WATER SYSTEM · 6,801 people · 2019 | 2/2 | SYR4 |
| Arsenic | 2 µg/L 20% of the EPA limit 10 µg/L Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 1/2 | SYR4 |
| Chromium | 2 µg/L 2% of the EPA limit 100 µg/L Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 1/2 | SYR4 |
| Lead | 1.95 µg/L 13% of the EPA limit 15 µg/L Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 1/2 | SYR4 |
| Gross Beta Particle Activity | 1.4645 pCi/L No EPA limit set Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2012 | 1/2 | SYR4 |
| Selenium | 1 µg/L 2% of the EPA limit 50 µg/L Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2019 | 1/2 | SYR4 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: CASITAS MUNICIPAL WATER DIST · 11,005 people · 2023 | 2/2 | 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 Oak View
| Supplier | Population served |
|---|---|
| CASITAS MUNICIPAL WATER DIST | 11,005 |
| OJAI WATER SYSTEM | 6,801 |
Frequently asked questions about Oak View tap water
Is Oak View tap water safe to drink?
EPA testing detected 23 contaminants in the water serving Oak View. 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 Oak View?
2 public water suppliers report drinking-water monitoring for Oak View, California to the EPA. Each is listed above with its population served.
What contaminants are in Oak View's water?
The contaminants EPA monitoring detected in Oak View include Nitrate-Nitrite, Nitrate, Fluoride, Barium, TTHM. 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.