What was found in ZIP 94087
The level at this ZIP's main supplier, the highest level anywhere in it, the EPA limit for each, and where the figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate | 6300 µg/L 63% of the EPA limit 10000 µg/L Main supplier: CITY OF SUNNYVALE · 157,566 people · 2019
Highest in the ZIP: 8440.5604 µg/L — CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 2/2 | SYR4 |
| Nitrate-Nitrite | 7100 µg/L 71% of the EPA limit 10000 µg/L Highest in the ZIP: CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 1/2 | SYR4 |
| Fluoride | 212.99999999999994 µg/L 5.3% of the EPA limit 4000 µg/L Main supplier: CITY OF SUNNYVALE · 157,566 people · 2018 | 2/2 | SYR4 |
| Barium | 130 µg/L 6.5% of the EPA limit 2000 µg/L Main supplier: CITY OF SUNNYVALE · 157,566 people · 2018
Highest in the ZIP: 183.92244999999997 µg/L — CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 2/2 | SYR4 |
| TTHM | 60.37 µg/L 75% of the EPA limit 80 µg/L Main supplier: CITY OF SUNNYVALE · 157,566 people · 2019
Highest in the ZIP: 60.51 µg/L — CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 2/2 | SYR4 |
| Chloroform | 46.925 µg/L No EPA limit set Main supplier: CITY OF SUNNYVALE · 157,566 people · 2019 | 2/2 | SYR4 |
| Total Haloacetic Acids (HAA5) | 42.44999999999999 µg/L 71% of the EPA limit 60 µg/L Main supplier: CITY OF SUNNYVALE · 157,566 people · 2019 | 2/2 | SYR4 |
| Dibromochloromethane | 26.335 µg/L No EPA limit set Main supplier: CITY OF SUNNYVALE · 157,566 people · 2019 | 2/2 | SYR4 |
| Dichloroacetic Acid | 22 µg/L No EPA limit set Main supplier: CITY OF SUNNYVALE · 157,566 people · 2019 | 2/2 | SYR4 |
| Bromoform | 20.259999999999998 µg/L No EPA limit set Main supplier: CITY OF SUNNYVALE · 157,566 people · 2019 | 2/2 | SYR4 |
| Bromodichloromethane | 18.479999999999997 µg/L No EPA limit set Main supplier: CITY OF SUNNYVALE · 157,566 people · 2019
Highest in the ZIP: 19.557999999999996 µg/L — CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 2/2 | SYR4 |
| Trichloroacetic Acid | 19 µg/L No EPA limit set Main supplier: CITY OF SUNNYVALE · 157,566 people · 2019 | 2/2 | SYR4 |
| Dibromoacetic Acid | 12 µg/L No EPA limit set Main supplier: CITY OF SUNNYVALE · 157,566 people · 2019 | 2/2 | SYR4 |
| Chromium | 10.35245 µg/L 10% of the EPA limit 100 µg/L Highest in the ZIP: CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 1/2 | SYR4 |
| Monochloroacetic Acid | 4.879999999999999 µg/L No EPA limit set Main supplier: CITY OF SUNNYVALE · 157,566 people · 2019 | 2/2 | SYR4 |
| Selenium | 3.9272499999999986 µg/L 7.9% of the EPA limit 50 µg/L Highest in the ZIP: CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 1/2 | SYR4 |
| Copper | 3.741399999999999 µg/L 0.3% of the EPA limit 1300 µg/L Highest in the ZIP: CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 1/2 | SYR4 |
| Monobromoacetic Acid | 2.075 µg/L No EPA limit set Main supplier: CITY OF SUNNYVALE · 157,566 people · 2019 | 2/2 | SYR4 |
| Combined Uranium | 1.980806 µg/L 6.6% of the EPA limit 30 µg/L Highest in the ZIP: CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 1/2 | SYR4 |
| Arsenic | 0.5176 µg/L 5.2% of the EPA limit 10 µg/L Highest in the ZIP: CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 1/2 | SYR4 |
| Lead | 0.3208 µg/L 2.1% of the EPA limit 15 µg/L Highest in the ZIP: CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 1/2 | SYR4 |
| Antimony, Total | 0.0181 µg/L 0.3% of the EPA limit 6 µg/L Highest in the ZIP: CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 1/2 | SYR4 |
| Cadmium | 0.0125 µg/L 0.2% of the EPA limit 5 µg/L Highest in the ZIP: CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 1/2 | SYR4 |
| Thallium, Total | 0.0080 µg/L 0.4% of the EPA limit 2 µg/L Highest in the ZIP: CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 1/2 | SYR4 |
| PFHXS | 0.0035 µg/L No EPA limit set Highest in the ZIP: CWSC LOS ALTOS SUBURBAN · 69,973 people · 2025 | 1/2 | UCMR-5 |
| Beryllium, Total | 0.0020 µg/L 0.1% of the EPA limit 4 µg/L Highest in the ZIP: CWSC LOS ALTOS SUBURBAN · 69,973 people · 2019 | 1/2 | SYR4 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: CITY OF SUNNYVALE · 157,566 people · 2025
Highest in the ZIP: 0.0015 mg/L — CWSC LOS ALTOS SUBURBAN · 69,973 people · 2025 | 2/2 | 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.
Water suppliers serving ZIP 94087
| Supplier | State | Population served |
|---|---|---|
| CITY OF SUNNYVALE | CA | 157,566 |
| CWSC LOS ALTOS SUBURBAN | CA | 69,973 |
Frequently asked questions about ZIP 94087 tap water
Is the tap water in ZIP 94087 safe to drink?
EPA testing detected 27 contaminants across the water suppliers serving ZIP 94087. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and your utility's annual Consumer Confidence Report for the official status.
Which water suppliers serve ZIP 94087?
2 public water suppliers report EPA drinking-water monitoring for ZIP 94087. Each is listed above with its population served.
What contaminants are in ZIP 94087's water?
EPA monitoring detected Nitrate, Nitrate-Nitrite, Fluoride, Barium, TTHM, and others across this ZIP's suppliers. The full list with levels and sources is above.