What was found in Oceanside'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 | 13804.999999999984 µg/L 138% of the EPA limit, at the 95th percentile of samples — 10000 µg/L Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Nitrate-Nitrite | 11249.99999999999 µg/L 112% of the EPA limit, at the 95th percentile of samples — 10000 µg/L Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Fluoride | 395.34999999999997 µg/L 9.9% of the EPA limit 4000 µg/L Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Nitrite | 390.1499999999999 µg/L 39% of the EPA limit 1000 µg/L Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Barium | 179.5 µg/L 9% of the EPA limit 2000 µg/L Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| TTHM | 60.785 µg/L 76% of the EPA limit 80 µg/L Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Chromium | 53 µg/L 53% of the EPA limit 100 µg/L Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Lithium | 38 µg/L No EPA limit set Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2024 | 1/1 | UCMR-5 |
| Combined Uranium | 33.67399999999999 µg/L 112% of the EPA limit, at the 95th percentile of samples — 30 µg/L Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Total Haloacetic Acids (HAA5) | 28 µg/L 47% of the EPA limit 60 µg/L Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Toluene | 21 µg/L 2.1% of the EPA limit 1000 µg/L Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Monochloroacetic Acid | 20.719999999999995 µg/L No EPA limit set Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Bromodichloromethane | 20.34 µg/L No EPA limit set Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Dibromochloromethane | 19.384999999999998 µg/L No EPA limit set Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Chloroform | 18.61 µg/L No EPA limit set Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Dichloroacetic Acid | 14.139999999999997 µg/L No EPA limit set Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Bromoform | 8.959999999999999 µg/L No EPA limit set Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Dibromoacetic Acid | 7.314999999999998 µg/L No EPA limit set Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Trichloroacetic Acid | 6.534999999999999 µg/L No EPA limit set Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Monobromoacetic Acid | 2.7699999999999996 µg/L No EPA limit set Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Trichloroethylene | 2.7 µg/L 54% of the EPA limit 5 µg/L Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Arsenic | 2 µg/L 20% of the EPA limit 10 µg/L Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| 1,2-Dichloropropane | 0.8850 µg/L 18% of the EPA limit 5 µg/L Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2019 | 1/1 | SYR4 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: OCEANSIDE, CITY OF · 171,483 people · 2024 | 1/1 | 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 Oceanside
| Supplier | Population served |
|---|---|
| OCEANSIDE, CITY OF | 171,483 |
Frequently asked questions about Oceanside tap water
Is Oceanside tap water safe to drink?
EPA testing detected 24 contaminants in the water serving Oceanside. 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 Oceanside?
1 public water supplier report drinking-water monitoring for Oceanside, California to the EPA. Each is listed above with its population served.
What contaminants are in Oceanside's water?
The contaminants EPA monitoring detected in Oceanside include Nitrate, Nitrate-Nitrite, Fluoride, Nitrite, 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.