Tap Water Quality Report
Tap water quality in Oxnard, California
Tap water in Oxnard, California receives a grade of D (63/100) from TapWaterSafety.org. It's served by OXNARD WATER DEPT. The most significant water quality concerns are: Haloacetic acids (HAA5) significantly above health guideline; Arsenic significantly above health guideline; Haloacetic acids (HAA9) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in Oxnard's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving Oxnard.
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.
Arsenic significantly above health guideline
Moderate concernArsenic detected at 1.38 ppb, 344x above the EWG health guideline of 0.004 ppb.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 12.0 ppb, 199x above the EWG health guideline of 0.06 ppb.
EPA compliance record
Official U.S. EPA records for OXNARD WATER DEPT (system ID CA5610007) for the last 3 years. Checked 2026-10-07.
Source: U.S. EPA Enforcement and Compliance History Online (ECHO), from the Safe Drinking Water Information System. See EPA's full report.
Recommended filters for Oxnard
Filters matched to the specific contaminants in Oxnard's water supply.
Carbon filter certified for VOCs (NSF/ANSI 53)
$180-$599Activated carbon is effective for disinfection byproducts. Look for NSF/ANSI 53 VOC reduction.
Reverse osmosis certified for arsenic (NSF/ANSI 58)
$429-$599Reverse osmosis certified under NSF/ANSI 58 for arsenic is the most reliable home option.
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 Oxnard'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 (HAA5) Disinfection byproduct |
36.2 ppb | 0.1 | 60.0 | 60 | — | — | — | 362× over |
| Arsenic Heavy metal |
1.38 ppb | 0.004 | 10.0 | 10 | 10 | 0.004 | — | 344× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
12.0 ppb | 0.06 | — | — | — | — | — | 199× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
23.7 ppb | 0.15 | 80.0 | 100 | — | — | — | 158× over |
| Dibromoacetic acid Disinfection byproduct |
3.93 ppb | 0.03 | — | — | — | — | — | 131× over |
| Dibromochloromethane Disinfection byproduct |
8.34 ppb | 0.1 | — | — | — | — | — | 83× over |
| Bromodichloromethane Disinfection byproduct |
2.93 ppb | 0.06 | — | — | — | — | — | 49× over |
| Bromoform Disinfection byproduct |
11.4 ppb | 0.5 | — | — | — | — | — | 23× over |
| Nitrate Inorganic |
1.97 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 14× over |
| Nitrate and nitrite Inorganic |
1.81 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 13× over |
| Chromium (hexavalent) Heavy metal |
0.225 ppb | 0.02 | — | — | — | — | — | 11× over |
| Uranium Radiological |
4.07 pCi/L | 0.43 | 20.0 | 30 | 30 | 0.43 | — | 9.5× over |
| Bromate Disinfection byproduct |
0.213 ppb | 0.1 | 10.0 | 10 | 10 | 0.1 | — | 2.1× over |
| Chloroform Disinfection byproduct |
0.808 ppb | 0.4 | — | — | — | — | — | 2.0× over |
| Dichloroacetic acid Disinfection byproduct |
0.219 ppb | 0.2 | — | — | — | — | — | 1.1× over |
| Trichloroacetic acid Disinfection byproduct |
0.0765 ppb | 0.1 | — | — | — | — | — | Below guideline |
| Selenium Heavy metal |
8.01 ppb | 30.0 | 50.0 | 20 | 40 | 30 | — | Below guideline |
| Molybdenum Other |
8.96 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
13.5 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Chlorate Disinfection byproduct |
16.3 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
1.48 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
36.1 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| 1,4-Dioxane Semi-volatile organic compound |
0.0133 ppb | 0.35 | — | — | 50 | 1 | — | Below guideline |
| Chloromethane Other |
0.0441 ppb | 2.69 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.0543 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.858 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| 1-Butanol Other |
0.175 ppb | — | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.6 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Lithium Other |
31.8 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 OXNARD WATER DEPT.