Water Quality Report · Updated October 07, 2026
CALIFORNIA WATER SERVICE CO. - ELA
CALIFORNIA WATER SERVICE CO. - ELA delivers tap water graded F (51/100) by TapWaterSafety.org. The utility serves approximately 152,474 residents in SAN JOSE, California using surface water (purchased). The most significant water quality concerns are: PFAS contamination; Perfluorohexane sulfonate (PFHXS) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline; Arsenic significantly above health guideline. For questions, the utility can be reached at 408-367-8490.
Is SAN JOSE tap water safe to drink?
CALIFORNIA WATER SERVICE CO. - ELA delivers tap water that earns a grade of F (51/100) from TapWaterSafety.org — a poor rating, with significant contamination concerns and/or recent violations.
The utility serves 152,474 residents in SAN JOSE, drawing from surface water (purchased).
Public testing data identifies 23 contaminants in this water above EWG's health-based guidelines, including: Perfluorooctane sulfonate (PFOS), Perfluorohexane sulfonate (PFHXS), Haloacetic acids (HAA5), Arsenic, Haloacetic acids (HAA9), Bromochloroacetic acid, Chromium (hexavalent), Perfluorooctanoic acid (PFOA), Nitrate, Dibromoacetic acid, Nitrate and nitrite, Total trihalomethanes (TTHMs), Perfluorononanoic acid (PFNA), Bromodichloromethane, Dibromochloromethane, 1,4-Dioxane, Trichloroacetic acid, Dichloroacetic acid, Perfluorodecanoic acid (PFDA), Tetrachloroethylene (perchloroethylene), Uranium, Radium, combined (-226 and -228)*, Chloroform. For most residents, a properly certified home filter at the kitchen tap is the most cost-effective way to reduce exposure to whatever's in your water. See our filter recommendations below, matched specifically to this utility's contaminant profile.
EPA compliance record
Official U.S. EPA records for CALIFORNIA WATER SERVICE CO. - ELA (system ID CA1910036) 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.
Quick actions for SAN JOSE residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for CALIFORNIA WATER SERVICE CO. - ELA.
PFAS contamination
Severe concernPerfluorononanoic acid (PFNA), Perfluorooctane sulfonate (PFOS) detected. PFAS are persistent chemicals linked to cancer and immune effects with no known safe exposure threshold.
Perfluorohexane sulfonate (PFHXS) significantly above health guideline
Moderate concernPerfluorohexane sulfonate (PFHXS) detected at 2.53 ppt, 2525x above the EWG health guideline of 0.001 ppt.
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 0.983 ppb, 246x above the EWG health guideline of 0.004 ppb.
Contact CALIFORNIA WATER SERVICE CO. - ELA
Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.
General Contact
Treatment Plant
Recommended water filters for SAN JOSE
Filters matched to the specific contaminants in this 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.
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.
Score breakdown
This utility's overall score of 51/100 breaks down across five weighted components. Read the full methodology →
Contaminants detected — international standards comparison
Every contaminant detected, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal (the strictest US benchmark). 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 |
|---|---|---|---|---|---|---|---|---|
| Perfluorooctane sulfonate (PFOS) PFAS |
10.5 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | EPA violation |
| Perfluorohexane sulfonate (PFHXS) PFAS |
2.53 ppt | 0.001 | 10.0 | — | — | — | — | 2525× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
36.2 ppb | 0.1 | 60.0 | 60 | — | — | — | 362× over |
| Arsenic Heavy metal |
0.983 ppb | 0.004 | 10.0 | 10 | 10 | 0.004 | — | 246× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
5.79 ppb | 0.06 | — | — | — | — | — | 97× over |
| Bromochloroacetic acid Disinfection byproduct |
1.14 ppb | 0.02 | — | — | — | — | — | 57× over |
| Chromium (hexavalent) Heavy metal |
0.86 ppb | 0.02 | — | — | — | — | — | 43× over |
| Perfluorooctanoic acid (PFOA) PFAS |
3.05 ppt | 0.09 | 4.0 | 100 | 100 | 0.007 | — | 34× over |
| Nitrate Inorganic |
3.48 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 25× over |
| Dibromoacetic acid Disinfection byproduct |
0.674 ppb | 0.03 | — | — | — | — | — | 22× over |
| Nitrate and nitrite Inorganic |
2.9 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 21× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
2.46 ppb | 0.15 | 80.0 | 100 | — | — | — | 16× over |
| Perfluorononanoic acid (PFNA) PFAS |
0.083 ppt | 0.006 | 10.0 | — | — | — | — | 14× over |
| Bromodichloromethane Disinfection byproduct |
0.672 ppb | 0.06 | — | — | — | — | — | 11× over |
| Dibromochloromethane Disinfection byproduct |
0.913 ppb | 0.1 | — | — | — | — | — | 9.1× over |
| 1,4-Dioxane Semi-volatile organic compound |
2.6 ppb | 0.35 | — | — | 50 | 1 | — | 7.4× over |
| Trichloroacetic acid Disinfection byproduct |
0.628 ppb | 0.1 | — | — | — | — | — | 6.3× over |
| Dichloroacetic acid Disinfection byproduct |
1.09 ppb | 0.2 | — | — | — | — | — | 5.4× over |
| Perfluorodecanoic acid (PFDA) PFAS |
0.02 ppt | 0.006 | — | — | — | — | — | 3.3× over |
| Tetrachloroethylene (perchloroethylene) Volatile organic compound |
0.124 ppb | 0.06 | 5.0 | — | — | — | — | 2.1× over |
| Uranium Radiological |
0.77 pCi/L | 0.43 | 20.0 | 30 | 30 | 0.43 | — | 1.8× over |
| Radium, combined (-226 and -228)* Radiological |
0.07 pCi/L | 0.05 | 5.0 | — | — | — | — | 1.4× over |
| Chloroform Disinfection byproduct |
0.527 ppb | 0.4 | — | — | — | — | — | 1.3× over |
| Bromoform Disinfection byproduct |
0.481 ppb | 0.5 | — | — | — | — | — | Below guideline |
| Chlorate Disinfection byproduct |
123.2 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Perchlorate Disinfection byproduct |
0.409 ppb | 1.0 | — | — | — | — | — | Below guideline |
| Trichloroethylene Volatile organic compound |
0.152 ppb | 0.4 | 5.0 | 10 | 20 | 1.7 | — | Below guideline |
| Vanadium Other |
3.02 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Aluminum* Heavy metal |
77.5 ppb | 600.0 | — | 200 | — | 600 | — | Below guideline |
| N-Nitrosodimethylamine (NDMA) Other |
0.386 ppt | 3.0 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
64.6 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Molybdenum Other |
3.63 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Selenium Heavy metal |
0.984 ppb | 30.0 | 50.0 | 20 | 40 | 30 | — | Below guideline |
| Manganese Heavy metal |
2.98 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Perfluorobutanoic Acid (PFBA) PFAS |
3.68 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA) PFAS |
2.66 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA) PFAS |
2.33 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoroheptanoic acid (PFHPA) PFAS |
0.624 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
1.18 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.786 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| 1,1-Dichloroethane Volatile organic compound |
0.000501 ppb | 3.0 | — | — | — | — | — | Below guideline |
| 1,1-Dichloroethylene Volatile organic compound |
0.405 ppb | — | 7.0 | — | — | — | — | Below guideline |
| 4-Androstene-3,17-dione Other |
0.013 ppt | — | — | — | — | — | — | Below guideline |
| Chlorodifluoromethane Other |
0.031 ppb | — | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.324 ppm | — | 4.0 | 1.5 | 1.5 | — | — | 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 (4th ed.), California OEHHA PHGs, EWG Tap Water Database.
CALIFORNIA WATER SERVICE CO. - ELA service area
This water system serves 1 community in Los Angeles County, California. Click any city for its dedicated tap water quality page.
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