What was found in ZIP 94558
The highest level seen across the suppliers serving this ZIP, the EPA limit for each, and where the figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate-Nitrite | 1000000 µg/L 10000% of the EPA limit, in the worst sample — 10000 µg/L | 2/3 | SYR4 |
| Nitrate | 1900 µg/L 19% of the EPA limit 10000 µg/L | 2/3 | SYR4 |
| Copper | 399 µg/L 31% of the EPA limit 1300 µg/L | 3/3 | SYR4 |
| Fluoride | 288 µg/L 7.2% of the EPA limit 4000 µg/L | 2/3 | SYR4 |
| Chlorite | 260 µg/L 26% of the EPA limit 1000 µg/L | 1/3 | SYR4 |
| TTHM | 140 µg/L 175% of the EPA limit, in the worst sample — 80 µg/L | 3/3 | SYR4 |
| Lead | 123 µg/L 820% of the EPA limit, in the worst sample — 15 µg/L | 2/3 | SYR4 |
| Chloroform | 120 µg/L No EPA limit set | 2/3 | SYR4 |
| Total Haloacetic Acids (HAA5) | 116 µg/L 193% of the EPA limit, in the worst sample — 60 µg/L | 2/3 | SYR4 |
| Chromium | 103 µg/L 103% of the EPA limit, in the worst sample — 100 µg/L | 2/3 | SYR4 |
| Trichloroacetic Acid | 62.8 µg/L No EPA limit set | 2/3 | SYR4 |
| Dichloroacetic Acid | 50.8 µg/L No EPA limit set | 2/3 | SYR4 |
| Barium | 38 µg/L 1.9% of the EPA limit 2000 µg/L | 1/3 | SYR4 |
| Bromodichloromethane | 32 µg/L No EPA limit set | 2/3 | SYR4 |
| Bromoform | 17.4 µg/L No EPA limit set | 2/3 | SYR4 |
| Dibromochloromethane | 17 µg/L No EPA limit set | 2/3 | SYR4 |
| Bromate | 11 µg/L 110% of the EPA limit, in the worst sample — 10 µg/L | 1/3 | SYR4 |
| Monochloroacetic Acid | 9.6 µg/L No EPA limit set | 1/3 | SYR4 |
| Arsenic | 7 µg/L 70% of the EPA limit 10 µg/L | 2/3 | SYR4 |
| Gross Beta Particle Activity | 5.8 pCi/L No EPA limit set | 2/3 | SYR4 |
| Dibromoacetic Acid | 4.4 µg/L No EPA limit set | 1/3 | SYR4 |
| Gross Alpha, Excl. Radon And U | 4.4 pCi/L 29% of the EPA limit 15 pCi/L | 1/3 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 3.8 µg/L 63% of the EPA limit 6 µg/L | 1/3 | SYR4 |
| Combined Uranium | 2.831 µg/L 9.4% of the EPA limit 30 µg/L | 2/3 | SYR4 |
| Cadmium | 2.3 µg/L 46% of the EPA limit 5 µg/L | 1/3 | SYR4 |
| Monobromoacetic Acid | 1.7 µg/L No EPA limit set | 1/3 | SYR4 |
| Trichloroethylene | 0.9700 µg/L 19% of the EPA limit 5 µg/L | 1/3 | SYR4 |
| Lead | 0.0107 mg/L 72% of the EPA limit 0.0150 mg/L | 3/3 | 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 single worst sample on
record — over 100% is worth reading, but is not by itself a violation.
Formal violations are listed separately.
Water suppliers serving ZIP 94558
| Supplier | State | Population served |
|---|---|---|
| NAPA, CITY OF | CA | 84,804 |
| CITY OF VALLEJO-LAKES SYSTEM | CA | 2,800 |
| KOHALA RANCH WATER CO. | HI | 850 |
Frequently asked questions about ZIP 94558 tap water
Is the tap water in ZIP 94558 safe to drink?
EPA testing detected 28 contaminants across the water suppliers serving ZIP 94558. 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 94558?
3 public water suppliers report EPA drinking-water monitoring for ZIP 94558. Each is listed above with its population served.
What contaminants are in ZIP 94558's water?
EPA monitoring detected Nitrate-Nitrite, Nitrate, Copper, Fluoride, Chlorite, and others across this ZIP's suppliers. The full list with levels and sources is above.