What was found in El Monte'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 | 235060 µg/L 2351% of the EPA limit, at the 95th percentile of samples — 10000 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 2/6 | SYR4 |
| Nitrate | 11752 µg/L 118% of the EPA limit, at the 95th percentile of samples — 10000 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 5/6 | SYR4 |
| Fluoride | 697 µg/L 17% of the EPA limit 4000 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019
Highest in the city: 994 µg/L — STERLING MUTUAL WATER COMPANY · 198 people · 2019 | 5/6 | SYR4 |
| Copper | 326.2 µg/L 25% of the EPA limit 1300 µg/L Highest in the city: EL MONTE-CITY, WATER DEPT. · 22,968 people · 2019 | 1/6 | SYR4 |
| Barium | 207 µg/L 10% of the EPA limit 2000 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 4/6 | SYR4 |
| Tetrachloroethylene | 110 µg/L 2200% of the EPA limit, at the 95th percentile of samples — 5 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 2/6 | SYR4 |
| Trichloroethylene | 61 µg/L 1220% of the EPA limit, at the 95th percentile of samples — 5 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 2/6 | SYR4 |
| Combined Uranium | 13.7378 µg/L 46% of the EPA limit 30 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 4/6 | SYR4 |
| 1,1-Dichloroethylene | 12 µg/L 171% of the EPA limit, at the 95th percentile of samples — 7 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 2/6 | SYR4 |
| Chloroform | 1.8 µg/L No EPA limit set Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019
Highest in the city: 11 µg/L — EL MONTE-CITY, WATER DEPT. · 22,968 people · 2019 | 3/6 | SYR4 |
| TTHM | 10 µg/L 13% of the EPA limit 80 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 4/6 | SYR4 |
| Carbon Tetrachloride | 7.83 µg/L 157% of the EPA limit, at the 95th percentile of samples — 5 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 2/6 | SYR4 |
| Gross Beta Particle Activity | 5.645 pCi/L No EPA limit set Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2018 | 1/6 | SYR4 |
| trans-1,2-Dichloroethylene | 5.325 µg/L 5.3% of the EPA limit 100 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 1/6 | SYR4 |
| Selenium | 5 µg/L 10% of the EPA limit 50 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 1/6 | SYR4 |
| Bromoform | 4.6 µg/L No EPA limit set Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019
Highest in the city: 4.82 µg/L — EL MONTE-CITY, WATER DEPT. · 22,968 people · 2019 | 3/6 | SYR4 |
| Dibromochloromethane | 4.43 µg/L No EPA limit set Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 4/6 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 4.4 µg/L 73% of the EPA limit 6 µg/L Highest in the city: EL MONTE-CITY, WATER DEPT. · 22,968 people · 2019 | 1/6 | SYR4 |
| Bromodichloromethane | 2.4 µg/L No EPA limit set Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019
Highest in the city: 3.9 µg/L — EL MONTE-CITY, WATER DEPT. · 22,968 people · 2019 | 4/6 | SYR4 |
| cis-1,2-Dichloroethylene | 3.8 µg/L 5.4% of the EPA limit 70 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 2/6 | SYR4 |
| 1,1,2-Trichloroethane | 3.775 µg/L 76% of the EPA limit 5 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 1/6 | SYR4 |
| Arsenic | 3.005 µg/L 30% of the EPA limit 10 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 3/6 | SYR4 |
| Monochloroacetic Acid | 3 µg/L No EPA limit set Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 1/6 | SYR4 |
| 1,2-Dichloroethane | 2.3 µg/L 46% of the EPA limit 5 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 1/6 | SYR4 |
| Dibromoacetic Acid | 1.91 µg/L No EPA limit set Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 2/6 | SYR4 |
| Total Haloacetic Acids (HAA5) | 1.91 µg/L 3.2% of the EPA limit 60 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 2/6 | SYR4 |
| Nitrite | 0.4700 µg/L 0% of the EPA limit 1000 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019
Highest in the city: 1.491 µg/L — EL MONTE-CITY, WATER DEPT. · 22,968 people · 2019 | 2/6 | SYR4 |
| Pentachlorophenol | 0.8470 µg/L 85% of the EPA limit 1 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 1/6 | SYR4 |
| Toluene | 0.5200 µg/L 0.1% of the EPA limit 1000 µg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2019 | 1/6 | SYR4 |
| Pfba | 0.0100 µg/L No EPA limit set Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2025 | 1/6 | UCMR-5 |
| Pfpea | 0.0056 µg/L No EPA limit set Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2025 | 1/6 | UCMR-5 |
| PFOS | 0.0044 µg/L No EPA limit set Highest in the city: EL MONTE-CITY, WATER DEPT. · 22,968 people · 2024 | 1/6 | UCMR-5 |
| PFHXS | 0.0032 µg/L No EPA limit set Highest in the city: EL MONTE-CITY, WATER DEPT. · 22,968 people · 2024 | 1/6 | UCMR-5 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: SAN GABRIEL VALLEY WATER CO.-EL MONTE · 248,000 people · 2023 | 6/6 | 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 El Monte
| Supplier | Population served |
|---|---|
| SAN GABRIEL VALLEY WATER CO.-EL MONTE | 248,000 |
| EL MONTE-CITY, WATER DEPT. | 22,968 |
| SAN GABRIEL VALLEY WATER CO-MONTEBELLO 1 | 9,630 |
| DEL RIO MUTUAL | 700 |
| HEMLOCK MUTUAL WATER CO. | 686 |
| STERLING MUTUAL WATER COMPANY | 198 |
Frequently asked questions about El Monte tap water
Is El Monte tap water safe to drink?
EPA testing detected 34 contaminants in the water serving El Monte. 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 El Monte?
6 public water suppliers report drinking-water monitoring for El Monte, California to the EPA. Each is listed above with its population served.
What contaminants are in El Monte's water?
The contaminants EPA monitoring detected in El Monte include Nitrate-Nitrite, Nitrate, Fluoride, Copper, 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.