Tap Water Quality Report
Tap water quality in OCEANSIDE, California
Tap water in OCEANSIDE, California receives a grade of F (53/100) from TapWaterSafety.org. It's served by OCEANSIDE, CITY OF. The most significant water quality concerns are: PFAS contamination; Haloacetic acids (HAA9) significantly above health guideline; Arsenic* significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in OCEANSIDE's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving OCEANSIDE.
PFAS contamination
Severe concernPerfluorooctane sulfonate (PFOS) detected. PFAS are persistent chemicals linked to cancer and immune effects with no known safe exposure threshold.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 29.6 ppb, 493x above the EWG health guideline of 0.06 ppb.
Arsenic* significantly above health guideline
Moderate concernArsenic* detected at 1.49 ppb, 373x above the EWG health guideline of 0.004 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 36.2 ppb, 362x above the EWG health guideline of 0.1 ppb.
Recommended filters for OCEANSIDE
Filters matched to the specific contaminants in OCEANSIDE's water supply.
Reverse Osmosis or NSF P473 certified carbon
$80-$750Activated carbon and RO are the only technologies proven to remove PFAS at certified levels.
Carbon block (NSF/ANSI 42 + 53)
$40-$750Activated carbon is highly effective for disinfection byproducts like TTHM and HAA5.
Reverse Osmosis
$249-$750Arsenic is most effectively removed by reverse osmosis. Some specialized adsorptive filters also work.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
All contaminants detected in OCEANSIDE's tap water
Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. Why we show multiple standards →
| Contaminant | Detected | EWG US health-based |
EPA US legal |
EU DWD Europe |
WHO global |
CA PHG strictest US |
Tested sample year |
Status |
|---|---|---|---|---|---|---|---|---|
| Haloacetic acids (HAA9) Disinfection byproduct |
29.6 ppb | 0.06 | — | — | — | — | — | 493× over |
| Arsenic* Heavy metal |
1.49 ppb | 0.004 | 10.0 | 10 | 10 | 0.004 | — | 373× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
36.2 ppb | 0.1 | 60.0 | 60 | — | — | — | 362× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
29.3 ppb | 0.15 | 80.0 | 100 | — | — | — | 196× over |
| Bromodichloromethane Disinfection byproduct |
8.85 ppb | 0.06 | — | — | — | — | — | 148× over |
| Dibromoacetic acid Disinfection byproduct |
2.58 ppb | 0.03 | — | — | — | — | — | 86× over |
| Dibromochloromethane Disinfection byproduct |
8.38 ppb | 0.1 | — | — | — | — | — | 84× over |
| Trichloroacetic acid Disinfection byproduct |
3.58 ppb | 0.1 | — | — | — | — | — | 36× over |
| Dichloroacetic acid Disinfection byproduct |
5.68 ppb | 0.2 | — | — | — | — | — | 28× over |
| Bromate* Disinfection byproduct |
2.39 ppb | 0.1 | 10.0 | 10 | 10 | 0.1 | — | 24× over |
| Chloroform Disinfection byproduct |
9.35 ppb | 0.4 | — | — | — | — | — | 23× over |
| Uranium Radiological |
4.27 pCi/L | 0.43 | 20.0 | 30 | 30 | 0.43 | — | 9.9× over |
| Bromoform Disinfection byproduct |
2.74 ppb | 0.5 | — | — | — | — | — | 5.5× over |
| Nitrate* Inorganic |
0.145 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 1.0× over |
| Perfluorooctane sulfonate (PFOS) PFAS |
0.25 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | Below guideline |
| Chromium (hexavalent) Heavy metal |
0.0087 ppb | 0.02 | — | — | — | — | — | Below guideline |
| Chlorate Disinfection byproduct |
89.2 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Nitrate and nitrite* Inorganic |
0.04 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | Below guideline |
| Molybdenum Other |
3.84 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
1.53 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Aluminum Heavy metal |
34.8 ppb | 600.0 | — | 200 | — | 600 | — | Below guideline |
| Barium Heavy metal |
40.0 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| 1,4-Dioxane Semi-volatile organic compound |
0.0143 ppb | 0.35 | — | — | 50 | 1 | — | Below guideline |
| Manganese Heavy metal |
0.309 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
1.4 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.779 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA)* PFAS |
0.275 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Bromide* Other |
160.7 ppb | — | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.0209 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Lithium Other |
24.7 ppb | — | — | — | — | — | — | Below guideline |
All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.
Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines, California OEHHA PHGs, EWG Tap Water Database.
Treatment plant contact info
For service issues, water quality concerns, or to request a Consumer Confidence Report from OCEANSIDE, CITY OF.