Tap Water Quality Report
Tap water quality in San Diego, California
Tap water in San Diego, California receives a grade of C (76/100) from TapWaterSafety.org. It's served by San Diego Water Utilities. The most significant water quality concerns are: Haloacetic Acids (HAA5) significantly above health guideline; Chromium-6 detected. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database, and San Diego's published Consumer Confidence Report.
What's in San Diego's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving San Diego.
Haloacetic Acids (HAA5) significantly above health guideline
Moderate concernHaloacetic Acids (HAA5) detected at 34.7 ppb, 347x above the EWG health guideline of 0.1 ppb.
Chromium-6 detected
Moderate concernChromium-6 detected at 0.3 ppb.
Recommended filters for San Diego
Filters matched to the specific contaminants in San Diego's water supply.
Carbon block (NSF/ANSI 42 + 53)
$40-$750Activated carbon is highly effective for disinfection byproducts like TTHM and HAA5.
Reverse Osmosis
$249-$750Chromium-6 requires reverse osmosis for reliable removal. Standard carbon filters do not address it.
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 San Diego'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 |
34.7 ppb | 0.1 | 60 | 60 | — | — | 2024 | 347× over |
| Total Trihalomethanes (TTHMs) Disinfection byproduct |
71.1 ppb | 0.6 | 80 | 100 | — | — | 2022 | 118× over |
| Chromium-6 (Hexavalent) Heavy metal |
0.347 ppb | 0.02 | — | — | — | 0.02 | 2022 | 17× over |
| Nitrate Inorganic |
1.28 mg/L | 0.14 | 10 | 11.3 | 11.3 | 10 | 2023 | 9.1× over |
| Contaminant | Detected (2024) | EWG | EPA | EU DWD | WHO | CA PHG | Status |
|---|---|---|---|---|---|---|---|
| Haloacetic Acids (HAA5) Disinfection byproduct |
34.7 ppb | 0.1 | 60 | 60 | — | — | 347× over |
| Contaminant | Detected (2023) | EWG | EPA | EU DWD | WHO | CA PHG | Status |
|---|---|---|---|---|---|---|---|
| Nitrate Inorganic |
1.28 mg/L | 0.14 | 10 | 11.3 | 11.3 | 10 | 9.1× over |
| Contaminant | Detected (2022) | EWG | EPA | EU DWD | WHO | CA PHG | Status |
|---|---|---|---|---|---|---|---|
| Total Trihalomethanes (TTHMs) Disinfection byproduct |
71.1 ppb | 0.6 | 80 | 100 | — | — | 118× over |
| Chromium-6 (Hexavalent) Heavy metal |
0.347 ppb | 0.02 | — | — | — | 0.02 | 17× over |
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 San Diego Water Utilities.
General Contact
Water Quality Contact
For questions about contaminants or test results.