What was found in Orange'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 | 3590.01 µg/L 36% of the EPA limit 10000 µg/L Main supplier: CITY OF ORANGE · 120,770 people · 2019
Highest in the city: 4270 µg/L — EAST ORANGE COUNTY WD - RZ · 3,464 people · 2019 | 2/3 | SYR4 |
| Nitrate-Nitrite | 3191 µg/L 32% of the EPA limit 10000 µg/L Main supplier: CITY OF ORANGE · 120,770 people · 2019
Highest in the city: 4171 µg/L — EAST ORANGE COUNTY WD - RZ · 3,464 people · 2019 | 2/3 | SYR4 |
| Fluoride | 452 µg/L 11% of the EPA limit 4000 µg/L Main supplier: CITY OF ORANGE · 120,770 people · 2019 | 2/3 | SYR4 |
| Barium | 123 µg/L 6.2% of the EPA limit 2000 µg/L Main supplier: CITY OF ORANGE · 120,770 people · 2019 | 1/3 | SYR4 |
| TTHM | 59.67 µg/L 75% of the EPA limit 80 µg/L Main supplier: CITY OF ORANGE · 120,770 people · 2019 | 3/3 | SYR4 |
| Lithium | 35.2774 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2025 | 1/3 | UCMR-5 |
| Total Haloacetic Acids (HAA5) | 21.8 µg/L 36% of the EPA limit 60 µg/L Main supplier: CITY OF ORANGE · 120,770 people · 2019
Highest in the city: 25.84 µg/L — EAST ORANGE COUNTY WD - RZ · 3,464 people · 2019 | 3/3 | SYR4 |
| Dibromochloromethane | 20 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2019 | 3/3 | SYR4 |
| Chloroform | 17.985 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2019 | 3/3 | SYR4 |
| Bromodichloromethane | 16.49 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2019
Highest in the city: 16.8 µg/L — EAST ORANGE COUNTY WD - WZ · 0 people · 2019 | 3/3 | SYR4 |
| Combined Uranium | 13.1209 µg/L 44% of the EPA limit 30 µg/L Main supplier: CITY OF ORANGE · 120,770 people · 2019 | 2/3 | SYR4 |
| Bromoform | 11.7 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2019
Highest in the city: 13.055 µg/L — EAST ORANGE COUNTY WD - RZ · 3,464 people · 2019 | 3/3 | SYR4 |
| Monochloroacetic Acid | 2.46 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2019
Highest in the city: 12 µg/L — EAST ORANGE COUNTY WD - RZ · 3,464 people · 2019 | 3/3 | SYR4 |
| Dichloroacetic Acid | 10.73 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2019
Highest in the city: 10.996 µg/L — EAST ORANGE COUNTY WD - RZ · 3,464 people · 2019 | 3/3 | SYR4 |
| Trichloroacetic Acid | 8.57 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2019
Highest in the city: 9.137 µg/L — EAST ORANGE COUNTY WD - RZ · 3,464 people · 2019 | 3/3 | SYR4 |
| Dibromoacetic Acid | 6.62 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2019
Highest in the city: 8.29 µg/L — EAST ORANGE COUNTY WD - RZ · 3,464 people · 2019 | 3/3 | SYR4 |
| Arsenic | 5.58 µg/L 56% of the EPA limit 10 µg/L Main supplier: CITY OF ORANGE · 120,770 people · 2019 | 1/3 | SYR4 |
| Monobromoacetic Acid | 1.76 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2019
Highest in the city: 2.239 µg/L — EAST ORANGE COUNTY WD - WZ · 0 people · 2019 | 3/3 | SYR4 |
| Pfpea | 0.0177 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2025 | 1/3 | UCMR-5 |
| PFOS | 0.0170 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2025 | 1/3 | UCMR-5 |
| Pfba | 0.0126 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2025 | 1/3 | UCMR-5 |
| PFHXS | 0.0102 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2025 | 1/3 | UCMR-5 |
| Pfhxa | 0.0101 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2025 | 1/3 | UCMR-5 |
| PFOA | 0.0093 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2025 | 1/3 | UCMR-5 |
| Lead | 0.0023 mg/L 16% of the EPA limit 0.0150 mg/L Main supplier: CITY OF ORANGE · 120,770 people · 2024
Highest in the city: 0.0055 mg/L — EAST ORANGE COUNTY WD - RZ · 3,464 people · 2024 | 2/3 | LCR |
| PFBS | 0.0033 µg/L No EPA limit set Main supplier: CITY OF ORANGE · 120,770 people · 2025 | 1/3 | 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 Orange
| Supplier | Population served |
|---|---|
| CITY OF ORANGE | 120,770 |
| EAST ORANGE COUNTY WD - RZ | 3,464 |
| EAST ORANGE COUNTY WD - WZ | 0 |
Frequently asked questions about Orange tap water
Is Orange tap water safe to drink?
EPA testing detected 26 contaminants in the water serving Orange. 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 Orange?
3 public water suppliers report drinking-water monitoring for Orange, California to the EPA. Each is listed above with its population served.
What contaminants are in Orange's water?
The contaminants EPA monitoring detected in Orange include Nitrate, Nitrate-Nitrite, 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.