What was found in Santa Clara'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 | 6079.999999999998 µg/L 61% of the EPA limit 10000 µg/L Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019
Highest in the city: 337999.9999999998 µg/L — CHEMEKETA PARK MUTUAL WATER COMPANY · 346 people · 2019 | 2/3 | SYR4 |
| Nitrate | 5600 µg/L 56% of the EPA limit 10000 µg/L Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019 | 2/3 | SYR4 |
| Fluoride | 177.99999999999997 µg/L 4.4% of the EPA limit 4000 µg/L Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019
Highest in the city: 370 µg/L — CHEMEKETA PARK MUTUAL WATER COMPANY · 346 people · 2019 | 2/3 | SYR4 |
| Barium | 167.99999999999997 µg/L 8.4% of the EPA limit 2000 µg/L Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019 | 2/3 | SYR4 |
| TTHM | 71 µg/L 89% of the EPA limit 80 µg/L Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019 | 2/3 | SYR4 |
| Chloroform | 51.94999999999999 µg/L No EPA limit set Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019 | 2/3 | SYR4 |
| Total Haloacetic Acids (HAA5) | 45 µg/L 75% of the EPA limit 60 µg/L Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019
Highest in the city: 51.74999999999999 µg/L — CHEMEKETA PARK MUTUAL WATER COMPANY · 346 people · 2019 | 2/3 | SYR4 |
| Dibromochloromethane | 32 µg/L No EPA limit set Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019 | 2/3 | SYR4 |
| Trichloroacetic Acid | 22 µg/L No EPA limit set Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019
Highest in the city: 27.499999999999996 µg/L — CHEMEKETA PARK MUTUAL WATER COMPANY · 346 people · 2019 | 2/3 | SYR4 |
| Dichloroacetic Acid | 25 µg/L No EPA limit set Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019 | 2/3 | SYR4 |
| Bromoform | 24 µg/L No EPA limit set Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019 | 2/3 | SYR4 |
| Bromodichloromethane | 18 µg/L No EPA limit set Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019
Highest in the city: 19.549999999999997 µg/L — CHEMEKETA PARK MUTUAL WATER COMPANY · 346 people · 2019 | 2/3 | SYR4 |
| Dibromoacetic Acid | 12 µg/L No EPA limit set Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019 | 2/3 | SYR4 |
| Lithium | 11 µg/L No EPA limit set Main supplier: CITY OF SANTA CLARA · 130,746 people · 2025 | 1/3 | UCMR-5 |
| Lead | 7.544999999999996 µg/L 50% of the EPA limit 15 µg/L Highest in the city: CHEMEKETA PARK MUTUAL WATER COMPANY · 346 people · 2019 | 1/3 | SYR4 |
| Arsenic | 4.68 µg/L 47% of the EPA limit 10 µg/L Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019 | 2/3 | SYR4 |
| Chromium | 2.625 µg/L 2.6% of the EPA limit 100 µg/L Highest in the city: CHEMEKETA PARK MUTUAL WATER COMPANY · 346 people · 2019 | 1/3 | SYR4 |
| Monochloroacetic Acid | 2.2 µg/L No EPA limit set Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019 | 1/3 | SYR4 |
| Monobromoacetic Acid | 1.7149999999999999 µg/L No EPA limit set Main supplier: CITY OF SANTA CLARA · 130,746 people · 2019 | 2/3 | SYR4 |
| Selenium | 1.67 µg/L 3.3% of the EPA limit 50 µg/L Highest in the city: CHEMEKETA PARK MUTUAL WATER COMPANY · 346 people · 2019 | 1/3 | SYR4 |
| Nitrite | 0.4900 µg/L 0% of the EPA limit 1000 µg/L Highest in the city: CHEMEKETA PARK MUTUAL WATER COMPANY · 346 people · 2019 | 1/3 | SYR4 |
| Cadmium | 0.2200 µg/L 4.4% of the EPA limit 5 µg/L Highest in the city: CHEMEKETA PARK MUTUAL WATER COMPANY · 346 people · 2019 | 1/3 | SYR4 |
| Lead | 0.0027 mg/L 18% of the EPA limit 0.0150 mg/L Main supplier: CITY OF SANTA CLARA · 130,746 people · 2025
Highest in the city: 0.0182 mg/L — CHEMEKETA PARK MUTUAL WATER COMPANY · 346 people · 2025 | 2/3 | 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 Santa Clara
| Supplier | Population served |
|---|---|
| CITY OF SANTA CLARA | 130,746 |
| CHEMEKETA PARK MUTUAL WATER COMPANY | 346 |
| LEE'S ORCHARD OWNERS ASSOCIATION | 35 |
Frequently asked questions about Santa Clara tap water
Is Santa Clara tap water safe to drink?
EPA testing detected 23 contaminants in the water serving Santa Clara. 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 Santa Clara?
3 public water suppliers report drinking-water monitoring for Santa Clara, California to the EPA. Each is listed above with its population served.
What contaminants are in Santa Clara's water?
The contaminants EPA monitoring detected in Santa Clara 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.