What was found in Highland'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 | 530000 µg/L 5300% of the EPA limit, at the 95th percentile of samples — 10000 µg/L Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| Nitrate | 10848 µg/L 108% of the EPA limit, at the 95th percentile of samples — 10000 µg/L Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| Fluoride | 2600 µg/L 65% of the EPA limit 4000 µg/L Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| TTHM | 78.66 µg/L 98% of the EPA limit 80 µg/L Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| Lithium | 56.2 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2025 | 1/1 | UCMR-5 |
| Combined Uranium | 42.2415 µg/L 141% of the EPA limit, at the 95th percentile of samples — 30 µg/L Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| Chloroform | 35.84 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| Dibromochloromethane | 32.07 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| Total Haloacetic Acids (HAA5) | 28.87 µg/L 48% of the EPA limit 60 µg/L Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| Bromodichloromethane | 23.6 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| Bromoform | 19.305 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| Trichloroacetic Acid | 18.225 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| Dichloroacetic Acid | 13.6 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| Dibromoacetic Acid | 12.43 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| Arsenic | 6.065 µg/L 61% of the EPA limit 10 µg/L Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| Tetrachloroethylene | 2.84 µg/L 57% of the EPA limit 5 µg/L Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| Monobromoacetic Acid | 1.3 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| 1,2-DIBROMO-3-CHLOROPROPANE | 0.0120 µg/L 6% of the EPA limit 0.2000 µg/L Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2019 | 1/1 | SYR4 |
| PFOS | 0.0120 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2025 | 1/1 | UCMR-5 |
| PFOA | 0.0090 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2025 | 1/1 | UCMR-5 |
| PFBS | 0.0089 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2025 | 1/1 | UCMR-5 |
| Pfhxa | 0.0047 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2025 | 1/1 | UCMR-5 |
| Pfpea | 0.0047 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2025 | 1/1 | UCMR-5 |
| PFHXS | 0.0040 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2025 | 1/1 | UCMR-5 |
| Pfhpa | 0.0031 µg/L No EPA limit set Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2025 | 1/1 | UCMR-5 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: EAST VALLEY WATER DISTRICT · 108,629 people · 2024 | 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.
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 Highland
| Supplier | Population served |
|---|---|
| EAST VALLEY WATER DISTRICT | 108,629 |
Frequently asked questions about Highland tap water
Is Highland tap water safe to drink?
EPA testing detected 26 contaminants in the water serving Highland. 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 Highland?
1 public water supplier report drinking-water monitoring for Highland, California to the EPA. Each is listed above with its population served.
What contaminants are in Highland's water?
The contaminants EPA monitoring detected in Highland include Nitrate-Nitrite, Nitrate, Fluoride, TTHM, Lithium. 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.