What was found in Wasco'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 | 10000 µg/L 100% of the EPA limit 10000 µg/L Main supplier: WASCO, CITY OF · 22,757 people · 2019 | 3/3 | SYR4 |
| Fluoride | 124.1 µg/L 3.1% of the EPA limit 4000 µg/L Main supplier: WASCO, CITY OF · 22,757 people · 2019
Highest in the city: 313 µg/L — POND MUTUAL WATER COMPANY · 48 people · 2019 | 2/3 | SYR4 |
| Barium | 71.1 µg/L 3.6% of the EPA limit 2000 µg/L Main supplier: WASCO, CITY OF · 22,757 people · 2019 | 2/3 | SYR4 |
| Arsenic | 4.45 µg/L 45% of the EPA limit 10 µg/L Main supplier: WASCO, CITY OF · 22,757 people · 2019
Highest in the city: 16.65 µg/L — POND MUTUAL WATER COMPANY · 48 people · 2019 | 3/3 | SYR4 |
| TTHM | 14.85 µg/L 19% of the EPA limit 80 µg/L Main supplier: WASCO, CITY OF · 22,757 people · 2019
Highest in the city: 16.43 µg/L — WASCO ST. PRISON RECEPTION CTR · 5,124 people · 2019 | 2/3 | SYR4 |
| Bromoform | 9.38 µg/L No EPA limit set Main supplier: WASCO, CITY OF · 22,757 people · 2019
Highest in the city: 11.67 µg/L — WASCO ST. PRISON RECEPTION CTR · 5,124 people · 2019 | 2/3 | SYR4 |
| Lithium | 9.1 µg/L No EPA limit set Highest in the city: WASCO ST. PRISON RECEPTION CTR · 5,124 people · 2025 | 1/3 | UCMR-5 |
| Chromium | 8.6 µg/L 8.6% of the EPA limit 100 µg/L Highest in the city: WASCO ST. PRISON RECEPTION CTR · 5,124 people · 2019 | 1/3 | SYR4 |
| Dibromochloromethane | 4.9 µg/L No EPA limit set Main supplier: WASCO, CITY OF · 22,757 people · 2019 | 2/3 | SYR4 |
| Total Haloacetic Acids (HAA5) | 3.5 µg/L 5.8% of the EPA limit 60 µg/L Main supplier: WASCO, CITY OF · 22,757 people · 2019 | 2/3 | SYR4 |
| Selenium | 2.5 µg/L 5% of the EPA limit 50 µg/L Main supplier: WASCO, CITY OF · 22,757 people · 2019
Highest in the city: 2.565 µg/L — WASCO ST. PRISON RECEPTION CTR · 5,124 people · 2018 | 2/3 | SYR4 |
| Dibromoacetic Acid | 2.085 µg/L No EPA limit set Main supplier: WASCO, CITY OF · 22,757 people · 2019
Highest in the city: 2.53 µg/L — WASCO ST. PRISON RECEPTION CTR · 5,124 people · 2019 | 2/3 | SYR4 |
| Trichloroacetic Acid | 2.35 µg/L No EPA limit set Main supplier: WASCO, CITY OF · 22,757 people · 2019 | 1/3 | SYR4 |
| Bromodichloromethane | 1.725 µg/L No EPA limit set Main supplier: WASCO, CITY OF · 22,757 people · 2019 | 2/3 | SYR4 |
| Combined Radium (-226 And -228) | 1.6335 pCi/L 33% of the EPA limit 5 pCi/L Highest in the city: WASCO ST. PRISON RECEPTION CTR · 5,124 people · 2015 | 1/3 | SYR4 |
| 1,1-Dichloroethylene | 1.295 µg/L 19% of the EPA limit 7 µg/L Highest in the city: WASCO ST. PRISON RECEPTION CTR · 5,124 people · 2019 | 1/3 | SYR4 |
| Chloroform | 0.8625 µg/L No EPA limit set Main supplier: WASCO, CITY OF · 22,757 people · 2019
Highest in the city: 0.9640 µg/L — WASCO ST. PRISON RECEPTION CTR · 5,124 people · 2019 | 2/3 | SYR4 |
| Ethylene Dibromide | 0.4100 µg/L 820% of the EPA limit, at the 95th percentile of samples — 0.0500 µg/L Main supplier: WASCO, CITY OF · 22,757 people · 2018 | 1/3 | SYR4 |
| 1,2-DIBROMO-3-CHLOROPROPANE | 0.0780 µg/L 39% of the EPA limit 0.2000 µg/L Main supplier: WASCO, CITY OF · 22,757 people · 2019 | 1/3 | SYR4 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: WASCO, CITY OF · 22,757 people · 2023 | 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 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 Wasco
| Supplier | Population served |
|---|---|
| WASCO, CITY OF | 22,757 |
| WASCO ST. PRISON RECEPTION CTR | 5,124 |
| POND MUTUAL WATER COMPANY | 48 |
Frequently asked questions about Wasco tap water
Is Wasco tap water safe to drink?
EPA testing detected 20 contaminants in the water serving Wasco. 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 Wasco?
3 public water suppliers report drinking-water monitoring for Wasco, California to the EPA. Each is listed above with its population served.
What contaminants are in Wasco's water?
The contaminants EPA monitoring detected in Wasco include Nitrate, Fluoride, Barium, Arsenic, 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.