What was found in ZIP 99403
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 | 1620 µg/L 16% of the EPA limit 10000 µg/L Main supplier: PUD #1 OF ASOTIN COUNTY · 21,930 people · 2019 | 1/1 | SYR4 |
| Lithium | 43.8 µg/L No EPA limit set Main supplier: PUD #1 OF ASOTIN COUNTY · 21,930 people · 2025 | 1/1 | UCMR-5 |
| TTHM | 8.368 µg/L 10% of the EPA limit 80 µg/L Main supplier: PUD #1 OF ASOTIN COUNTY · 21,930 people · 2019 | 1/1 | SYR4 |
| Bromoform | 4.962 µg/L No EPA limit set Main supplier: PUD #1 OF ASOTIN COUNTY · 21,930 people · 2019 | 1/1 | SYR4 |
| Dibromochloromethane | 2.6695 µg/L No EPA limit set Main supplier: PUD #1 OF ASOTIN COUNTY · 21,930 people · 2019 | 1/1 | SYR4 |
| Dibromoacetic Acid | 1.1065 µg/L No EPA limit set Main supplier: PUD #1 OF ASOTIN COUNTY · 21,930 people · 2019 | 1/1 | SYR4 |
| Total Haloacetic Acids (HAA5) | 1.1065 µg/L 1.8% of the EPA limit 60 µg/L Main supplier: PUD #1 OF ASOTIN COUNTY · 21,930 people · 2019 | 1/1 | SYR4 |
| Bromodichloromethane | 0.8440 µg/L No EPA limit set Main supplier: PUD #1 OF ASOTIN COUNTY · 21,930 people · 2019 | 1/1 | SYR4 |
| Chloroform | 0.2600 µg/L No EPA limit set Main supplier: PUD #1 OF ASOTIN COUNTY · 21,930 people · 2019 | 1/1 | SYR4 |
| Lead | 0.0035 mg/L 23% of the EPA limit 0.0150 mg/L Main supplier: PUD #1 OF ASOTIN COUNTY · 21,930 people · 2023 | 1/1 | 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 99403
| Supplier | State | Population served |
|---|---|---|
| PUD #1 OF ASOTIN COUNTY | WA | 21,930 |
Frequently asked questions about ZIP 99403 tap water
Is the tap water in ZIP 99403 safe to drink?
EPA testing detected 10 contaminants across the water suppliers serving ZIP 99403. 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 99403?
1 public water supplier report EPA drinking-water monitoring for ZIP 99403. Each is listed above with its population served.
What contaminants are in ZIP 99403's water?
EPA monitoring detected Nitrate, Lithium, TTHM, Bromoform, Dibromochloromethane, and others across this ZIP's suppliers. The full list with levels and sources is above.