What was found in San Juan Capistrano'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 |
|---|---|---|---|
| Lithium | 57.4 µg/L No EPA limit set Main supplier: SANTA MARGARITA WATER DISTRICT-ID9 · 39,684 people · 2025 | 1/1 | UCMR-5 |
| TTHM | 55.45 µg/L 69% of the EPA limit 80 µg/L Main supplier: SANTA MARGARITA WATER DISTRICT-ID9 · 39,684 people · 2019 | 1/1 | SYR4 |
| Total Haloacetic Acids (HAA5) | 25 µg/L 42% of the EPA limit 60 µg/L Main supplier: SANTA MARGARITA WATER DISTRICT-ID9 · 39,684 people · 2019 | 1/1 | SYR4 |
| Chloroform | 19 µg/L No EPA limit set Main supplier: SANTA MARGARITA WATER DISTRICT-ID9 · 39,684 people · 2019 | 1/1 | SYR4 |
| Dibromochloromethane | 19 µg/L No EPA limit set Main supplier: SANTA MARGARITA WATER DISTRICT-ID9 · 39,684 people · 2019 | 1/1 | SYR4 |
| Bromodichloromethane | 17 µg/L No EPA limit set Main supplier: SANTA MARGARITA WATER DISTRICT-ID9 · 39,684 people · 2019 | 1/1 | SYR4 |
| Dichloroacetic Acid | 10.85 µg/L No EPA limit set Main supplier: SANTA MARGARITA WATER DISTRICT-ID9 · 39,684 people · 2019 | 1/1 | SYR4 |
| Monochloroacetic Acid | 8.6 µg/L No EPA limit set Main supplier: SANTA MARGARITA WATER DISTRICT-ID9 · 39,684 people · 2019 | 1/1 | SYR4 |
| Bromoform | 7.945 µg/L No EPA limit set Main supplier: SANTA MARGARITA WATER DISTRICT-ID9 · 39,684 people · 2019 | 1/1 | SYR4 |
| Trichloroacetic Acid | 7.745 µg/L No EPA limit set Main supplier: SANTA MARGARITA WATER DISTRICT-ID9 · 39,684 people · 2019 | 1/1 | SYR4 |
| Monobromoacetic Acid | 6.4 µg/L No EPA limit set Main supplier: SANTA MARGARITA WATER DISTRICT-ID9 · 39,684 people · 2019 | 1/1 | SYR4 |
| Dibromoacetic Acid | 5.34 µg/L No EPA limit set Main supplier: SANTA MARGARITA WATER DISTRICT-ID9 · 39,684 people · 2019 | 1/1 | SYR4 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: SANTA MARGARITA WATER DISTRICT-ID9 · 39,684 people · 2024 | 1/1 | LCR |
Water suppliers serving San Juan Capistrano
| Supplier | Population served |
|---|---|
| SANTA MARGARITA WATER DISTRICT-ID9 | 39,684 |
Frequently asked questions about San Juan Capistrano tap water
Is San Juan Capistrano tap water safe to drink?
EPA testing detected 13 contaminants in the water serving San Juan Capistrano. 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 San Juan Capistrano?
1 public water supplier report drinking-water monitoring for San Juan Capistrano, California to the EPA. Each is listed above with its population served.
What contaminants are in San Juan Capistrano's water?
The contaminants EPA monitoring detected in San Juan Capistrano include Lithium, TTHM, Total Haloacetic Acids (HAA5), Chloroform, Dibromochloromethane. 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.