What was found in Escondido'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 | 500 µg/L 5% of the EPA limit 10000 µg/L Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019
Highest in the city: 8730 µg/L — DEL DIOS MUTUAL WATER COMPANY · 330 people · 2019 | 3/5 | SYR4 |
| Fluoride | 833.9999999999998 µg/L 21% of the EPA limit 4000 µg/L Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019 | 3/5 | SYR4 |
| Chlorite | 370 µg/L 37% of the EPA limit 1000 µg/L Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019 | 1/5 | SYR4 |
| Nitrate-Nitrite | 350 µg/L 3.5% of the EPA limit 10000 µg/L Highest in the city: DEL DIOS MUTUAL WATER COMPANY · 330 people · 2018 | 1/5 | SYR4 |
| Combined Uranium | 4.119849999999998 µg/L 14% of the EPA limit 30 µg/L Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2018
Highest in the city: 309.92 µg/L — OAKVALE PARK · 260 people · 2019 | 3/5 | SYR4 |
| Barium | 130.99999999999997 µg/L 6.5% of the EPA limit 2000 µg/L Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019 | 2/5 | SYR4 |
| TTHM | 69.25 µg/L 87% of the EPA limit 80 µg/L Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019
Highest in the city: 79.5 µg/L — RINCON DEL DIABLO MWD (ID-A) · 3,275 people · 2019 | 4/5 | SYR4 |
| Lithium | 30 µg/L No EPA limit set Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2023
Highest in the city: 43 µg/L — RINCON DEL DIABLO MWD (ID-1) · 30,757 people · 2025 | 2/5 | UCMR-5 |
| Total Haloacetic Acids (HAA5) | 29 µg/L 48% of the EPA limit 60 µg/L Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019
Highest in the city: 37.5 µg/L — RINCON DEL DIABLO MWD (ID-A) · 3,275 people · 2019 | 3/5 | SYR4 |
| Monochloroacetic Acid | 5.249999999999998 µg/L No EPA limit set Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019
Highest in the city: 30.250000000000004 µg/L — RINCON DEL DIABLO MWD (ID-A) · 3,275 people · 2019 | 3/5 | SYR4 |
| Bromodichloromethane | 24.25 µg/L No EPA limit set Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019
Highest in the city: 28.5 µg/L — RINCON DEL DIABLO MWD (ID-A) · 3,275 people · 2019 | 4/5 | SYR4 |
| Chloroform | 23 µg/L No EPA limit set Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019
Highest in the city: 27.5 µg/L — RINCON DEL DIABLO MWD (ID-A) · 3,275 people · 2019 | 3/5 | SYR4 |
| Dibromochloromethane | 22 µg/L No EPA limit set Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019 | 4/5 | SYR4 |
| Bromoform | 8.025 µg/L No EPA limit set Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019
Highest in the city: 17 µg/L — OAKVALE PARK · 260 people · 2018 | 4/5 | SYR4 |
| Dichloroacetic Acid | 13.649999999999977 µg/L No EPA limit set Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019 | 3/5 | SYR4 |
| Trichloroacetic Acid | 9.479999999999995 µg/L No EPA limit set Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019 | 3/5 | SYR4 |
| Copper | 6.539999999999999 µg/L 0.5% of the EPA limit 1300 µg/L Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019 | 1/5 | SYR4 |
| Dibromoacetic Acid | 5.6 µg/L No EPA limit set Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019
Highest in the city: 6.519999999999999 µg/L — RINCON DEL DIABLO MWD (ID-A) · 3,275 people · 2019 | 3/5 | SYR4 |
| Arsenic | 2.5 µg/L 25% of the EPA limit 10 µg/L Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019
Highest in the city: 5.8999999999999995 µg/L — DEL DIOS MUTUAL WATER COMPANY · 330 people · 2019 | 2/5 | SYR4 |
| Gross Beta Particle Activity | 3.8894999999999995 pCi/L No EPA limit set Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2018 | 1/5 | SYR4 |
| Monobromoacetic Acid | 3.8 µg/L No EPA limit set Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019 | 3/5 | SYR4 |
| Xylenes, Total | 0.2200 µg/L 0% of the EPA limit 10000 µg/L Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2019 | 1/5 | SYR4 |
| Pfba | 0.0100 µg/L No EPA limit set Highest in the city: RINCON DEL DIABLO MWD (ID-1) · 30,757 people · 2025 | 1/5 | UCMR-5 |
| Lead | 0.0011 mg/L 7.3% of the EPA limit 0.0150 mg/L Main supplier: ESCONDIDO, CITY OF · 137,044 people · 2024
Highest in the city: 0.0033 mg/L — RINCON DEL DIABLO MWD (ID-A) · 3,275 people · 2026 | 5/5 | 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 Escondido
| Supplier | Population served |
|---|---|
| ESCONDIDO, CITY OF | 137,044 |
| RINCON DEL DIABLO MWD (ID-1) | 30,757 |
| RINCON DEL DIABLO MWD (ID-A) | 3,275 |
| DEL DIOS MUTUAL WATER COMPANY | 330 |
| OAKVALE PARK | 260 |
Frequently asked questions about Escondido tap water
Is Escondido tap water safe to drink?
EPA testing detected 24 contaminants in the water serving Escondido. 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 Escondido?
5 public water suppliers report drinking-water monitoring for Escondido, California to the EPA. Each is listed above with its population served.
What contaminants are in Escondido's water?
The contaminants EPA monitoring detected in Escondido include Nitrate, Fluoride, Chlorite, Nitrate-Nitrite, Combined Uranium. 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.