What was found in Covina'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 | 5540 µg/L 55% of the EPA limit 10000 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019
Highest in the city: 896500 µg/L — SUBURBAN WATER SYSTEMS - SATIVA · 4,363 people · 2013 | 2/7 | SYR4 |
| Nitrate | 5650 µg/L 56% of the EPA limit 10000 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019 | 3/7 | SYR4 |
| Fluoride | 470 µg/L 12% of the EPA limit 4000 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019
Highest in the city: 578 µg/L — SUBURBAN WATER SYSTEMS-LA MIRADA · 56,793 people · 2018 | 4/7 | SYR4 |
| Barium | 150 µg/L 7.5% of the EPA limit 2000 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019 | 3/7 | SYR4 |
| TTHM | 50.75 µg/L 63% of the EPA limit 80 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019
Highest in the city: 130 µg/L — SUBURBAN WATER SYSTEMS-COVINA KNOLLS · 1,437 people · 2019 | 7/7 | SYR4 |
| Chloroform | 20.45 µg/L No EPA limit set Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019
Highest in the city: 58.5 µg/L — SUBURBAN WATER SYSTEMS-COVINA KNOLLS · 1,437 people · 2019 | 6/7 | SYR4 |
| Lithium | 54 µg/L No EPA limit set Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2025 | 3/7 | UCMR-5 |
| Dibromochloromethane | 14 µg/L No EPA limit set Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019
Highest in the city: 43.75 µg/L — SUBURBAN WATER SYSTEMS-COVINA KNOLLS · 1,437 people · 2019 | 7/7 | SYR4 |
| Total Haloacetic Acids (HAA5) | 18 µg/L 30% of the EPA limit 60 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019
Highest in the city: 42.9 µg/L — SUBURBAN WATER SYSTEMS-COVINA KNOLLS · 1,437 people · 2019 | 6/7 | SYR4 |
| Bromodichloromethane | 16 µg/L No EPA limit set Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019
Highest in the city: 30.75 µg/L — SUBURBAN WATER SYSTEMS-COVINA KNOLLS · 1,437 people · 2019 | 7/7 | SYR4 |
| Dichloroacetic Acid | 11 µg/L No EPA limit set Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019
Highest in the city: 23 µg/L — COVINA-CITY, WATER DEPT. · 33,300 people · 2019 | 5/7 | SYR4 |
| Bromoform | 6.975 µg/L No EPA limit set Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019
Highest in the city: 21.6 µg/L — SUBURBAN WATER SYSTEMS-COVINA KNOLLS · 1,437 people · 2019 | 7/7 | SYR4 |
| Trichloroacetic Acid | 7.5 µg/L No EPA limit set Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019
Highest in the city: 19.55 µg/L — SUBURBAN WATER SYSTEMS-COVINA KNOLLS · 1,437 people · 2019 | 5/7 | SYR4 |
| Dibromoacetic Acid | 4.6 µg/L No EPA limit set Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019
Highest in the city: 17.4 µg/L — SUBURBAN WATER SYSTEMS-COVINA KNOLLS · 1,437 people · 2019 | 6/7 | SYR4 |
| Chromium | 16.7 µg/L 17% of the EPA limit 100 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019 | 1/7 | SYR4 |
| Combined Uranium | 2.21265 µg/L 7.4% of the EPA limit 30 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2016
Highest in the city: 8.1056 µg/L — SUBURBAN WATER SYSTEMS - SATIVA · 4,363 people · 2015 | 4/7 | SYR4 |
| Trichloroethylene | 7.7 µg/L 154% of the EPA limit, at the 95th percentile of samples — 5 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019 | 3/7 | SYR4 |
| Monobromoacetic Acid | 6.7 µg/L No EPA limit set Highest in the city: COVINA-CITY, WATER DEPT. · 33,300 people · 2019 | 3/7 | SYR4 |
| Arsenic | 2.49 µg/L 25% of the EPA limit 10 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019
Highest in the city: 4.74 µg/L — SUBURBAN WATER SYSTEMS-LA MIRADA · 56,793 people · 2018 | 4/7 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 3.76 µg/L 63% of the EPA limit 6 µg/L Highest in the city: SUBURBAN WATER SYSTEMS-WHITTIER · 66,045 people · 2019 | 1/7 | SYR4 |
| 1,1-Dichloroethylene | 3.7 µg/L 53% of the EPA limit 7 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019 | 1/7 | SYR4 |
| Monochloroacetic Acid | 3.7 µg/L No EPA limit set Highest in the city: SUBURBAN WATER SYSTEMS-WHITTIER · 66,045 people · 2019 | 1/7 | SYR4 |
| Tetrachloroethylene | 1.9 µg/L 38% of the EPA limit 5 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019 | 3/7 | SYR4 |
| Chlorobenzene | 1.329 µg/L 1.3% of the EPA limit 100 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019 | 1/7 | SYR4 |
| cis-1,2-Dichloroethylene | 1.2 µg/L 1.7% of the EPA limit 70 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019
Highest in the city: 1.31 µg/L — SUBURBAN WATER SYSTEMS-WHITTIER · 66,045 people · 2019 | 2/7 | SYR4 |
| trans-1,2-Dichloroethylene | 1.3 µg/L 1.3% of the EPA limit 100 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019 | 1/7 | SYR4 |
| Carbon Tetrachloride | 0.6590 µg/L 13% of the EPA limit 5 µg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2019 | 1/7 | SYR4 |
| PFOS | 0.0160 µg/L No EPA limit set Highest in the city: SUBURBAN WATER SYSTEMS-LA MIRADA · 56,793 people · 2025 | 2/7 | UCMR-5 |
| Pfba | 0.0062 µg/L No EPA limit set Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2025
Highest in the city: 0.0095 µg/L — SUBURBAN WATER SYSTEMS-LA MIRADA · 56,793 people · 2025 | 3/7 | UCMR-5 |
| PFOA | 0.0070 µg/L No EPA limit set Highest in the city: SUBURBAN WATER SYSTEMS-LA MIRADA · 56,793 people · 2025 | 2/7 | UCMR-5 |
| PFBS | 0.0036 µg/L No EPA limit set Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2025
Highest in the city: 0.0042 µg/L — SUBURBAN WATER SYSTEMS-LA MIRADA · 56,793 people · 2025 | 3/7 | UCMR-5 |
| Pfpea | 0.0035 µg/L No EPA limit set Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2025
Highest in the city: 0.0040 µg/L — SUBURBAN WATER SYSTEMS-WHITTIER · 66,045 people · 2024 | 3/7 | UCMR-5 |
| PFHXS | 0.0038 µg/L No EPA limit set Highest in the city: SUBURBAN WATER SYSTEMS-LA MIRADA · 56,793 people · 2025 | 1/7 | UCMR-5 |
| Pfhxa | 0.0033 µg/L No EPA limit set Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2025 | 2/7 | UCMR-5 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: SUBURBAN WATER SYSTEMS-SAN JOSE · 168,843 people · 2025 | 7/7 | 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 Covina
| Supplier | Population served |
|---|---|
| SUBURBAN WATER SYSTEMS-SAN JOSE | 168,843 |
| SUBURBAN WATER SYSTEMS-WHITTIER | 66,045 |
| SUBURBAN WATER SYSTEMS-LA MIRADA | 56,793 |
| COVINA-CITY, WATER DEPT. | 33,300 |
| SUBURBAN WATER SYSTEMS-GLENDORA | 5,249 |
| SUBURBAN WATER SYSTEMS - SATIVA | 4,363 |
| SUBURBAN WATER SYSTEMS-COVINA KNOLLS | 1,437 |
Frequently asked questions about Covina tap water
Is Covina tap water safe to drink?
EPA testing detected 35 contaminants in the water serving Covina. 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 Covina?
7 public water suppliers report drinking-water monitoring for Covina, California to the EPA. Each is listed above with its population served.
What contaminants are in Covina's water?
The contaminants EPA monitoring detected in Covina 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.