What was found in Pauma Valley'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 | 41000 µg/L 410% of the EPA limit, at the 95th percentile of samples — 10000 µg/L Highest in the city: YUIMA MUNICIPAL WATER DISTRICT IDA · 769 people · 2019 | 4/10 | SYR4 |
| Nitrate | 1720 µg/L 17% of the EPA limit 10000 µg/L Main supplier: Pauma · 5,700 people · 2019
Highest in the city: 31640 µg/L — YUIMA MUNICIPAL WATER DISTRICT IDA · 769 people · 2019 | 7/10 | SYR4 |
| Fluoride | 157 µg/L 3.9% of the EPA limit 4000 µg/L Main supplier: Pauma · 5,700 people · 2013
Highest in the city: 835 µg/L — RANCHO ESTATES MUTUAL WATER CO. · 200 people · 2018 | 8/10 | SYR4 |
| Lead | 171.1 µg/L 1141% of the EPA limit, at the 95th percentile of samples — 15 µg/L Highest in the city: RANCHO ESTATES MUTUAL WATER CO. · 200 people · 2018 | 3/10 | SYR4 |
| Barium | 10 µg/L 0.5% of the EPA limit 2000 µg/L Main supplier: Pauma · 5,700 people · 2013
Highest in the city: 140.5 µg/L — YUIMA MUNICIPAL WATER DISTRICT IDA · 769 people · 2019 | 8/10 | SYR4 |
| Combined Uranium | 4.917 µg/L 16% of the EPA limit 30 µg/L Main supplier: Pauma · 5,700 people · 2016
Highest in the city: 68.5028 µg/L — RANCHO ESTATES MUTUAL WATER CO. · 200 people · 2019 | 7/10 | SYR4 |
| Copper | 50 µg/L 3.8% of the EPA limit 1300 µg/L Highest in the city: RANCHO PAUMA MUTUAL WC · 899 people · 2019 | 4/10 | SYR4 |
| Thallium, Total | 38 µg/L 1900% of the EPA limit, at the 95th percentile of samples — 2 µg/L Highest in the city: RANCHO ESTATES MUTUAL WATER CO. · 200 people · 2018 | 1/10 | SYR4 |
| Selenium | 31.75 µg/L 64% of the EPA limit 50 µg/L Main supplier: Pauma · 5,700 people · 2013
Highest in the city: 37.8 µg/L — RANCHO ESTATES MUTUAL WATER CO. · 200 people · 2018 | 7/10 | SYR4 |
| TTHM | 12.95 µg/L 16% of the EPA limit 80 µg/L Main supplier: Pauma · 5,700 people · 2019
Highest in the city: 30.95 µg/L — YUIMA MUNICIPAL WATER DISTRICT IDA · 769 people · 2019 | 6/10 | SYR4 |
| Total Haloacetic Acids (HAA5) | 5.92 µg/L 9.9% of the EPA limit 60 µg/L Main supplier: Pauma · 5,700 people · 2019
Highest in the city: 19.85 µg/L — YUIMA MUNICIPAL WATER DISTRICT · 360 people · 2019 | 6/10 | SYR4 |
| Dibromochloromethane | 11.95 µg/L No EPA limit set Highest in the city: YUIMA MUNICIPAL WATER DISTRICT IDA · 769 people · 2019 | 3/10 | SYR4 |
| Bromoform | 11.325 µg/L No EPA limit set Highest in the city: RANCHO PAUMA MUTUAL WC · 899 people · 2019 | 3/10 | SYR4 |
| Arsenic | 6 µg/L 60% of the EPA limit 10 µg/L Main supplier: Pauma · 5,700 people · 2013
Highest in the city: 9.22 µg/L — PAUMA VALLEY WATER COMPANY · 185 people · 2019 | 5/10 | SYR4 |
| Toluene | 8.5 µg/L 0.9% of the EPA limit 1000 µg/L Highest in the city: YUIMA MUNICIPAL WATER DISTRICT · 360 people · 2017 | 3/10 | SYR4 |
| Bromodichloromethane | 7.635 µg/L No EPA limit set Highest in the city: YUIMA MUNICIPAL WATER DISTRICT IDA · 769 people · 2019 | 3/10 | SYR4 |
| Chloroform | 7.415 µg/L No EPA limit set Highest in the city: YUIMA MUNICIPAL WATER DISTRICT · 360 people · 2019 | 3/10 | SYR4 |
| Dichloroacetic Acid | 7.36 µg/L No EPA limit set Highest in the city: YUIMA MUNICIPAL WATER DISTRICT · 360 people · 2019 | 3/10 | SYR4 |
| Trichloroacetic Acid | 7.06 µg/L No EPA limit set Highest in the city: YUIMA MUNICIPAL WATER DISTRICT · 360 people · 2019 | 2/10 | SYR4 |
| Antimony, Total | 6.7 µg/L 112% of the EPA limit, at the 95th percentile of samples — 6 µg/L Highest in the city: PAUMA VALLEY WATER COMPANY · 185 people · 2019 | 2/10 | SYR4 |
| Dibromoacetic Acid | 6.24 µg/L No EPA limit set Highest in the city: RANCHO PAUMA MUTUAL WC · 899 people · 2019 | 3/10 | SYR4 |
| Gross Beta Particle Activity | 6.187 pCi/L No EPA limit set Highest in the city: PAUMA VALLEY WATER COMPANY · 185 people · 2019 | 3/10 | SYR4 |
| Gross Alpha, Excl. Radon And U | 6.009 pCi/L 40% of the EPA limit 15 pCi/L Main supplier: Pauma · 5,700 people · 2016 | 1/10 | SYR4 |
| Monochloroacetic Acid | 5.27 µg/L No EPA limit set Highest in the city: YUIMA MUNICIPAL WATER DISTRICT · 360 people · 2019 | 2/10 | SYR4 |
| Chromium | 2.5 µg/L 2.5% of the EPA limit 100 µg/L Highest in the city: YUIMA MUNICIPAL WATER DISTRICT · 360 people · 2017 | 2/10 | SYR4 |
| Dichloromethane | 2.3 µg/L 46% of the EPA limit 5 µg/L Highest in the city: La Jolla Western · 296 people · 2018 | 3/10 | SYR4 |
| Monobromoacetic Acid | 1.285 µg/L No EPA limit set Highest in the city: YUIMA MUNICIPAL WATER DISTRICT · 360 people · 2019 | 2/10 | SYR4 |
| Combined Radium (-226 And -228) | 0.3300 pCi/L 6.6% of the EPA limit 5 pCi/L Main supplier: Pauma · 5,700 people · 2017 | 1/10 | SYR4 |
| Nitrite | 0.1200 µg/L 0% of the EPA limit 1000 µg/L Highest in the city: PAUMA VALLEY WATER COMPANY · 185 people · 2019 | 1/10 | SYR4 |
| Lead | 0.0050 mg/L 33% of the EPA limit 0.0150 mg/L Main supplier: Pauma · 5,700 people · 2025 | 10/10 | 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 Pauma Valley
| Supplier | Population served |
|---|---|
| Pauma | 5,700 |
| La Jolla Eastern | 1,076 |
| RANCHO PAUMA MUTUAL WC | 899 |
| YUIMA MUNICIPAL WATER DISTRICT IDA | 769 |
| YUIMA MUNICIPAL WATER DISTRICT | 360 |
| La Jolla Western | 296 |
| RANCHO ESTATES MUTUAL WATER CO. | 200 |
| PAUMA VALLEY WATER COMPANY | 185 |
| LAZY H MUTUAL WATER COMPANY | 142 |
| Arviso - Mobile Home Park | 70 |
Frequently asked questions about Pauma Valley tap water
Is Pauma Valley tap water safe to drink?
EPA testing detected 30 contaminants in the water serving Pauma Valley. 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 Pauma Valley?
10 public water suppliers report drinking-water monitoring for Pauma Valley, California to the EPA. Each is listed above with its population served.
What contaminants are in Pauma Valley's water?
The contaminants EPA monitoring detected in Pauma Valley include Nitrate-Nitrite, Nitrate, Fluoride, Lead, Barium. 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.