Tap Water Quality Report
Tap water quality in San Diego, California
Tap water in San Diego, California receives a grade of D (60/100) from TapWaterSafety.org. It's served by SAN DIEGO, CITY OF. The most significant water quality concerns are: PFAS contamination; Haloacetic acids (HAA5) significantly above health guideline; Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
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.
PFAS contamination
Severe concernPerfluorooctane sulfonate (PFOS), Perfluorooctanoic acid (PFOA) detected. PFAS are persistent chemicals linked to cancer and immune effects with no known safe exposure threshold.
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.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 18.1 ppb, 302x above the EWG health guideline of 0.06 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 28.1 ppb, 188x above the EWG health guideline of 0.15 ppb.
EPA compliance record
Official U.S. EPA records for SAN DIEGO, CITY OF (system ID CA3710020) 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 San Diego
Filters matched to the specific contaminants in San Diego's water supply.
Filter certified for PFOA/PFOS (NSF/ANSI 53 or 58)
$180-$750Reverse osmosis and some carbon block filters reduce PFAS. Look for certification to NSF/ANSI 53 or 58 for PFOA/PFOS.
Carbon filter certified for VOCs (NSF/ANSI 53)
$180-$599Activated carbon is effective for disinfection byproducts. Look for NSF/ANSI 53 VOC reduction.
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 |
36.2 ppb | 0.1 | 60.0 | 60 | — | — | — | 362× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
18.1 ppb | 0.06 | — | — | — | — | — | 302× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
28.1 ppb | 0.15 | 80.0 | 100 | — | — | — | 188× over |
| Bromodichloromethane Disinfection byproduct |
7.58 ppb | 0.06 | — | — | — | — | — | 126× over |
| Dibromochloromethane Disinfection byproduct |
9.99 ppb | 0.1 | — | — | — | — | — | 100× over |
| Dibromoacetic acid Disinfection byproduct |
2.73 ppb | 0.03 | — | — | — | — | — | 91× over |
| Dichloroacetic acid Disinfection byproduct |
3.19 ppb | 0.2 | — | — | — | — | — | 16× over |
| Bromate Disinfection byproduct |
1.38 ppb | 0.1 | 10.0 | 10 | 10 | 0.1 | — | 14× over |
| Chloroform Disinfection byproduct |
5.37 ppb | 0.4 | — | — | — | — | — | 13× over |
| Bromoform Disinfection byproduct |
5.18 ppb | 0.5 | — | — | — | — | — | 10× over |
| Trichloroacetic acid Disinfection byproduct |
0.922 ppb | 0.1 | — | — | — | — | — | 9.2× over |
| Chlorite Disinfection byproduct |
286.5 ppb | 50.0 | 1000.0 | — | — | — | — | 5.7× over |
| Uranium Radiological |
2.07 pCi/L | 0.43 | 20.0 | 30 | 30 | 0.43 | — | 4.8× over |
| Chromium (hexavalent) Heavy metal |
0.044 ppb | 0.02 | — | — | — | — | — | 2.2× over |
| Perfluorooctanoic acid (PFOA) PFAS |
0.104 ppt | 0.09 | 4.0 | 100 | 100 | 0.007 | — | 1.2× over |
| Chlorate Disinfection byproduct |
152.2 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Perfluorooctane sulfonate (PFOS) PFAS |
0.096 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | Below guideline |
| Molybdenum Other |
3.6 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Perchlorate Disinfection byproduct |
0.0884 ppb | 1.0 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
45.1 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Bromochloromethane Other |
0.00155 ppb | 0.06 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.228 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
0.346 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Vanadium Other |
0.0498 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.711 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
0.0248 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Perfluorobutanoic Acid (PFBA) PFAS |
0.38 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA) PFAS |
0.2 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA) PFAS |
0.104 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Bromide Other |
42.3 ppb | — | — | — | — | — | — | Below guideline |
| Chlorodifluoromethane Other |
0.0209 ppb | — | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.587 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Lithium Other |
34.1 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 SAN DIEGO, CITY OF.
General Contact
Treatment Plant
ZIP codes served
San Diego's public water systems serve the following ZIP codes: