What was found in Temecula'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 | 5100 µg/L 51% of the EPA limit 10000 µg/L Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 3/3 | SYR4 |
| Fluoride | 3600 µg/L 90% of the EPA limit 4000 µg/L Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 3/3 | SYR4 |
| Barium | 222 µg/L 11% of the EPA limit 2000 µg/L Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 3/3 | SYR4 |
| Nitrite | 120 µg/L 12% of the EPA limit 1000 µg/L Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 1/3 | SYR4 |
| TTHM | 54 µg/L 68% of the EPA limit 80 µg/L Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 3/3 | SYR4 |
| Lithium | 44 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2024
Highest in the city: 50 µg/L — Pechanga · 29,100 people · 2024 | 2/3 | UCMR-5 |
| Monochloroacetic Acid | 30 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 1/3 | SYR4 |
| Bromoform | 26.1 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 2/3 | SYR4 |
| Total Haloacetic Acids (HAA5) | 21 µg/L 35% of the EPA limit 60 µg/L Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 2/3 | SYR4 |
| Arsenic | 18 µg/L 180% of the EPA limit, at the 95th percentile of samples — 10 µg/L Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 2/3 | SYR4 |
| Dibromochloromethane | 16.05 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 2/3 | SYR4 |
| Bromodichloromethane | 13 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 1/3 | SYR4 |
| Chloroform | 10 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 1/3 | SYR4 |
| Combined Uranium | 9.64402 µg/L 32% of the EPA limit 30 µg/L Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 3/3 | SYR4 |
| Selenium | 6.82 µg/L 14% of the EPA limit 50 µg/L Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 1/3 | SYR4 |
| Dibromoacetic Acid | 6.2 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 1/3 | SYR4 |
| Trichloroacetic Acid | 4.76 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 1/3 | SYR4 |
| Gross Beta Particle Activity | 4.6275 pCi/L No EPA limit set Highest in the city: OAK HAVEN ASSOCIATION · 120 people · 2018 | 1/3 | SYR4 |
| Dichloroacetic Acid | 4.52 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 1/3 | SYR4 |
| Chromium | 3.86 µg/L 3.9% of the EPA limit 100 µg/L Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 3/3 | SYR4 |
| Gross Alpha, Excl. Radon And U | 2.899 pCi/L 19% of the EPA limit 15 pCi/L Highest in the city: Pechanga · 29,100 people · 2016 | 1/3 | SYR4 |
| Monobromoacetic Acid | 2.68 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 1/3 | SYR4 |
| Toluene | 1.755 µg/L 0.2% of the EPA limit 1000 µg/L Highest in the city: OAK HAVEN ASSOCIATION · 120 people · 2018 | 1/3 | SYR4 |
| Dichloromethane | 0.6900 µg/L 14% of the EPA limit 5 µg/L Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 1/3 | SYR4 |
| Pentachlorophenol | 0.3300 µg/L 33% of the EPA limit 1 µg/L Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2019 | 1/3 | SYR4 |
| PFOS | 0.0160 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2024 | 1/3 | UCMR-5 |
| PFOA | 0.0110 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2024 | 1/3 | UCMR-5 |
| Pfpea | 0.0077 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2024
Highest in the city: 0.0089 µg/L — Pechanga · 29,100 people · 2024 | 2/3 | UCMR-5 |
| Pfba | 0.0078 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2024 | 1/3 | UCMR-5 |
| PFBS | 0.0073 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2024 | 2/3 | UCMR-5 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2025
Highest in the city: 0.0067 mg/L — OAK HAVEN ASSOCIATION · 120 people · 2024 | 3/3 | LCR |
| PFHXS | 0.0067 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2024 | 1/3 | UCMR-5 |
| Pfhxa | 0.0066 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2024 | 2/3 | UCMR-5 |
| Pfhpa | 0.0033 µg/L No EPA limit set Main supplier: RANCHO CALIFORNIA WATER DISTRICT · 146,147 people · 2024 | 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 Temecula
| Supplier | Population served |
|---|---|
| RANCHO CALIFORNIA WATER DISTRICT | 146,147 |
| Pechanga | 29,100 |
| OAK HAVEN ASSOCIATION | 120 |
Frequently asked questions about Temecula tap water
Is Temecula tap water safe to drink?
EPA testing detected 34 contaminants in the water serving Temecula. 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 Temecula?
3 public water suppliers report drinking-water monitoring for Temecula, California to the EPA. Each is listed above with its population served.
What contaminants are in Temecula's water?
The contaminants EPA monitoring detected in Temecula include Nitrate, Fluoride, Barium, Nitrite, 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.