What was found in Three Rivers'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 | 300 µg/L 3% of the EPA limit 10000 µg/L Main supplier: NPS-WOLVERTON · 2,940 people · 2019
Highest in the city: 740000 µg/L — SIERRA KING HOMEOWNERS ASSN · 260 people · 2019 | 8/11 | SYR4 |
| Nitrate | 474.6 µg/L 4.7% of the EPA limit 10000 µg/L Main supplier: NPS-WOLVERTON · 2,940 people · 2019
Highest in the city: 8600 µg/L — EAST THREE RIVERS MUTUAL WATER CORP · 40 people · 2019 | 10/11 | SYR4 |
| Fluoride | 1125 µg/L 28% of the EPA limit 4000 µg/L Highest in the city: SIERRA KING HOMEOWNERS ASSN · 260 people · 2019 | 10/11 | SYR4 |
| Barium | 111.9 µg/L 5.6% of the EPA limit 2000 µg/L Main supplier: NPS-WOLVERTON · 2,940 people · 2019
Highest in the city: 319.6 µg/L — NORTH KAWEAH MUTUAL WATER COMPANY · 560 people · 2019 | 8/11 | SYR4 |
| Copper | 290 µg/L 22% of the EPA limit 1300 µg/L Main supplier: NPS-WOLVERTON · 2,940 people · 2019 | 5/11 | SYR4 |
| Total Haloacetic Acids (HAA5) | 124 µg/L 207% of the EPA limit, at the 95th percentile of samples — 60 µg/L Main supplier: NPS-WOLVERTON · 2,940 people · 2019 | 6/11 | SYR4 |
| Combined Uranium | 108.174 µg/L 361% of the EPA limit, at the 95th percentile of samples — 30 µg/L Highest in the city: EAST THREE RIVERS MUTUAL WATER CORP · 40 people · 2019 | 7/11 | SYR4 |
| TTHM | 105.7 µg/L 132% of the EPA limit, at the 95th percentile of samples — 80 µg/L Main supplier: NPS-WOLVERTON · 2,940 people · 2019 | 7/11 | SYR4 |
| Chloroform | 100 µg/L No EPA limit set Main supplier: NPS-WOLVERTON · 2,940 people · 2019 | 4/11 | SYR4 |
| Trichloroacetic Acid | 96 µg/L No EPA limit set Main supplier: NPS-WOLVERTON · 2,940 people · 2019 | 4/11 | SYR4 |
| Arsenic | 49.3 µg/L 493% of the EPA limit, at the 95th percentile of samples — 10 µg/L Highest in the city: EAST THREE RIVERS MUTUAL WATER CORP · 40 people · 2019 | 7/11 | SYR4 |
| Dichloroacetic Acid | 40.45 µg/L No EPA limit set Main supplier: NPS-WOLVERTON · 2,940 people · 2019 | 5/11 | SYR4 |
| Bromoform | 23.2 µg/L No EPA limit set Main supplier: NPS-WOLVERTON · 2,940 people · 2019 | 7/11 | SYR4 |
| Dibromochloromethane | 8.05 µg/L No EPA limit set Main supplier: NPS-WOLVERTON · 2,940 people · 2019
Highest in the city: 17.7 µg/L — NORTH KAWEAH MUTUAL WATER COMPANY · 560 people · 2019 | 7/11 | SYR4 |
| Chromium | 2.5 µg/L 2.5% of the EPA limit 100 µg/L Main supplier: NPS-WOLVERTON · 2,940 people · 2019
Highest in the city: 14 µg/L — SOUTH KAWEAH MUTUAL WATER COMPANY · 384 people · 2019 | 4/11 | SYR4 |
| Lead | 13.63 µg/L 91% of the EPA limit 15 µg/L Main supplier: NPS-WOLVERTON · 2,940 people · 2019 | 5/11 | SYR4 |
| Bromodichloromethane | 5.5 µg/L No EPA limit set Main supplier: NPS-WOLVERTON · 2,940 people · 2019
Highest in the city: 12.58 µg/L — NORTH KAWEAH MUTUAL WATER COMPANY · 560 people · 2019 | 6/11 | SYR4 |
| Dibromoacetic Acid | 1.95 µg/L No EPA limit set Main supplier: NPS-WOLVERTON · 2,940 people · 2019
Highest in the city: 9.4 µg/L — NORTH KAWEAH MUTUAL WATER COMPANY · 560 people · 2018 | 6/11 | SYR4 |
| Selenium | 7.1 µg/L 14% of the EPA limit 50 µg/L Highest in the city: RIVER RETREAT MUTUAL WATER COMPANY · 40 people · 2018 | 4/11 | SYR4 |
| Cyanide | 5.4 µg/L 2.7% of the EPA limit 200 µg/L Highest in the city: NPS-ASH MOUNTAIN · 2,930 people · 2016 | 1/11 | SYR4 |
| Monochloroacetic Acid | 3.55 µg/L No EPA limit set Main supplier: NPS-WOLVERTON · 2,940 people · 2019
Highest in the city: 4.38 µg/L — NPS-ASH MOUNTAIN · 2,930 people · 2019 | 2/11 | SYR4 |
| Toluene | 1.5 µg/L 0.2% of the EPA limit 1000 µg/L Highest in the city: VILLAGE APARTMENTS · 33 people · 2019 | 1/11 | SYR4 |
| Cadmium | 1.2 µg/L 24% of the EPA limit 5 µg/L Highest in the city: EAST THREE RIVERS MUTUAL WATER CORP · 40 people · 2019 | 1/11 | SYR4 |
| Monobromoacetic Acid | 1 µg/L No EPA limit set Main supplier: NPS-WOLVERTON · 2,940 people · 2019 | 1/11 | SYR4 |
| Mercury | 0.4670 µg/L 23% of the EPA limit 2 µg/L Highest in the city: IMPROVEMENT DISTRICT NO. 1 · 200 people · 2019 | 2/11 | SYR4 |
| Lead | 0.0110 mg/L 73% of the EPA limit 0.0150 mg/L Main supplier: NPS-WOLVERTON · 2,940 people · 2025 | 11/11 | 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 Three Rivers
| Supplier | Population served |
|---|---|
| NPS-WOLVERTON | 2,940 |
| NPS-ASH MOUNTAIN | 2,930 |
| NORTH KAWEAH MUTUAL WATER COMPANY | 560 |
| SOUTH KAWEAH MUTUAL WATER COMPANY | 384 |
| SIERRA KING HOMEOWNERS ASSN | 260 |
| IMPROVEMENT DISTRICT NO. 1 | 200 |
| SOUTH FORK ESTATES MUTUAL WATER CO | 106 |
| DEER MEADOW MUTUAL WATER COMPANY | 70 |
| EAST THREE RIVERS MUTUAL WATER CORP | 40 |
| RIVER RETREAT MUTUAL WATER COMPANY | 40 |
| VILLAGE APARTMENTS | 33 |
Frequently asked questions about Three Rivers tap water
Is Three Rivers tap water safe to drink?
EPA testing detected 26 contaminants in the water serving Three Rivers. 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 Three Rivers?
11 public water suppliers report drinking-water monitoring for Three Rivers, California to the EPA. Each is listed above with its population served.
What contaminants are in Three Rivers's water?
The contaminants EPA monitoring detected in Three Rivers include Nitrate-Nitrite, Nitrate, Fluoride, Barium, Copper. 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.