What was found in San Juan Bautista'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 | 7320 µg/L 73% of the EPA limit 10000 µg/L Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2018
Highest in the city: 500000 µg/L — LOS MADRONES MWC · 36 people · 2019 | 4/4 | SYR4 |
| Nitrate | 13847.5 µg/L 138% of the EPA limit, at the 95th percentile of samples — 10000 µg/L Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2019 | 4/4 | SYR4 |
| Fluoride | 1064 µg/L 27% of the EPA limit 4000 µg/L Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2018
Highest in the city: 1280 µg/L — LOS MADRONES MWC · 36 people · 2019 | 4/4 | SYR4 |
| Nitrite | 490 µg/L 49% of the EPA limit 1000 µg/L Highest in the city: LOS MADRONES MWC · 36 people · 2019 | 1/4 | SYR4 |
| Barium | 140 µg/L 7% of the EPA limit 2000 µg/L Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2018 | 2/4 | SYR4 |
| TTHM | 17.931 µg/L 22% of the EPA limit 80 µg/L Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2019
Highest in the city: 82.2 µg/L — LOS MADRONES MWC · 36 people · 2019 | 3/4 | SYR4 |
| Total Haloacetic Acids (HAA5) | 5.695 µg/L 9.5% of the EPA limit 60 µg/L Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2019
Highest in the city: 36.7 µg/L — LOS MADRONES MWC · 36 people · 2019 | 3/4 | SYR4 |
| Bromoform | 10.75 µg/L No EPA limit set Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2019
Highest in the city: 33.8 µg/L — LOS MADRONES MWC · 36 people · 2019 | 3/4 | SYR4 |
| Chromium | 30.55 µg/L 31% of the EPA limit 100 µg/L Highest in the city: LOS MADRONES MWC · 36 people · 2019 | 1/4 | SYR4 |
| Dibromochloromethane | 5.703 µg/L No EPA limit set Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2019
Highest in the city: 26 µg/L — LOS MADRONES MWC · 36 people · 2019 | 3/4 | SYR4 |
| Bromodichloromethane | 3.131 µg/L No EPA limit set Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2019
Highest in the city: 25.7 µg/L — LOS MADRONES MWC · 36 people · 2019 | 3/4 | SYR4 |
| Combined Uranium | 8.35294 µg/L 28% of the EPA limit 30 µg/L Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2019
Highest in the city: 20.86 µg/L — LOS MADRONES MWC · 36 people · 2019 | 3/4 | SYR4 |
| Chloroform | 1.4975 µg/L No EPA limit set Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2019
Highest in the city: 17.95 µg/L — LOS MADRONES MWC · 36 people · 2019 | 3/4 | SYR4 |
| Dichloroacetic Acid | 1.5 µg/L No EPA limit set Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2019
Highest in the city: 15.1 µg/L — LOS MADRONES MWC · 36 people · 2019 | 3/4 | SYR4 |
| Dibromoacetic Acid | 5.74 µg/L No EPA limit set Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2019
Highest in the city: 14.7 µg/L — LOS MADRONES MWC · 36 people · 2019 | 3/4 | SYR4 |
| Toluene | 10.07 µg/L 1% of the EPA limit 1000 µg/L Highest in the city: LOS MADRONES MWC · 36 people · 2019 | 1/4 | SYR4 |
| Trichloroacetic Acid | 1.4 µg/L No EPA limit set Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2019
Highest in the city: 7 µg/L — LOS MADRONES MWC · 36 people · 2019 | 3/4 | SYR4 |
| Arsenic | 2.4 µg/L 24% of the EPA limit 10 µg/L Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2018
Highest in the city: 3.7 µg/L — LOS MADRONES MWC · 36 people · 2019 | 3/4 | SYR4 |
| Combined Radium (-226 And -228) | 2 pCi/L 40% of the EPA limit 5 pCi/L Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2018 | 1/4 | SYR4 |
| Monobromoacetic Acid | 2 µg/L No EPA limit set Highest in the city: LOS MADRONES MWC · 36 people · 2019 | 1/4 | SYR4 |
| Selenium | 1 µg/L 2% of the EPA limit 50 µg/L Highest in the city: LOS MADRONES MWC · 36 people · 2019 | 1/4 | SYR4 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: SAN JUAN BAUTISTA, CITY OF · 2,335 people · 2025
Highest in the city: 0.0126 mg/L — LOS MADRONES MWC · 36 people · 2023 | 4/4 | 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 San Juan Bautista
| Supplier | Population served |
|---|---|
| SAN JUAN BAUTISTA, CITY OF | 2,335 |
| MISSION FARM R.V. PARK | 110 |
| BETABEL RV RESORT | 49 |
| LOS MADRONES MWC | 36 |
Frequently asked questions about San Juan Bautista tap water
Is San Juan Bautista tap water safe to drink?
EPA testing detected 22 contaminants in the water serving San Juan Bautista. 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 Bautista?
4 public water suppliers report drinking-water monitoring for San Juan Bautista, California to the EPA. Each is listed above with its population served.
What contaminants are in San Juan Bautista's water?
The contaminants EPA monitoring detected in San Juan Bautista include Nitrate-Nitrite, Nitrate, Fluoride, Nitrite, 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.