Water Quality Report · Updated May 12, 2026

SAN JOSE WATER

Serving 1,039,920 residents in SAN JOSE, California .

National rank 8th percentile
California rank 24th percentile
Data confidence Medium
Quick answer

SAN JOSE WATER delivers tap water graded F (50/100) by TapWaterSafety.org. The utility serves approximately 1,039,920 residents in SAN JOSE, California using surface water. The most significant water quality concerns are: PFAS contamination; Perfluorohexane sulfonate (PFHXS) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline; Haloacetic acids (HAA9) significantly above health guideline; Arsenic detected. For questions, the utility can be reached at 408-918-7254.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?
1,039,920
People served
1
City served
45
Contaminants detected
20
Above health guidelines
0
EPA violations (5 yr)

Is SAN JOSE tap water safe to drink?

SAN JOSE WATER delivers tap water that earns a grade of F (50/100) from TapWaterSafety.org — a poor rating, with significant contamination concerns and/or recent violations.

The utility serves 1,039,920 residents in SAN JOSE, drawing from surface water.

Public testing data identifies 20 contaminants in this water above EWG's health-based guidelines, including: Perfluorohexane sulfonate (PFHXS), Haloacetic acids (HAA5), Haloacetic acids (HAA9), Total trihalomethanes (TTHMs), Dibromoacetic acid, Bromodichloromethane, Arsenic, Dibromochloromethane, Chromium (hexavalent), Perfluorononanoic acid (PFNA), Trichloroacetic acid, Dichloroacetic acid, Chloroform, Nitrate, Nitrate and nitrite, Bromoform, Perfluorooctane sulfonate (PFOS), Radium, combined (-226 and -228), Perfluorooctanoic acid (PFOA), Uranium. 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.

Top concerns in this water

Based on the most recent EPA and EWG data, these are the most significant water quality issues for SAN JOSE WATER.

PFAS contamination

Severe concern

Perfluorononanoic 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 concern

Perfluorohexane sulfonate (PFHXS) detected at 2.8 ppt, 2802x above the EWG health guideline of 0.001 ppt.

Haloacetic acids (HAA5) significantly above health guideline

Moderate concern

Haloacetic 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 concern

Haloacetic acids (HAA9) detected at 16.5 ppb, 276x above the EWG health guideline of 0.06 ppb.

Arsenic detected

Moderate concern

Arsenic detected at 0.47 ppb.

Contact SAN JOSE WATER

Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.

Recommended water filters for SAN JOSE

Filters matched to the specific contaminants in this water supply.

Reverse Osmosis or NSF P473 certified carbon

$80-$750

Activated carbon and RO are the only technologies proven to remove PFAS at certified levels.

AquaTru Countertop Reverse Osmosis
$449-$599 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Aquasana OptimH2O Reverse Osmosis + Claryum
$429-$549 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Waterdrop G3P800 Tankless RO
$600-$750 NSF 58, 372
View on retailer →
Waterdrop N1 Countertop RO
$249-$329 NSF 58, 372
View on retailer →
Clearly Filtered Pitcher Filter
$80-$95 NSF 42, 53, 401, P473
Editorial pick · affiliate link coming soon

Reverse Osmosis

$249-$750

Arsenic is most effectively removed by reverse osmosis. Some specialized adsorptive filters also work.

AquaTru Countertop Reverse Osmosis
$449-$599 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Aquasana OptimH2O Reverse Osmosis + Claryum
$429-$549 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Waterdrop G3P800 Tankless RO
$600-$750 NSF 58, 372
View on retailer →
Waterdrop N1 Countertop RO
$249-$329 NSF 58, 372
View on retailer →

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 50/100 breaks down across five weighted components. Read the full methodology →

Health Guideline Performance
10 / 40
Legal Compliance
20 / 20
High-Risk Contaminants
3 / 20
Compliance History
10 / 10
Source Water Vulnerability
7 / 10

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
Perfluorohexane sulfonate (PFHXS)
PFAS
2.8 ppt 0.001 10.0 2802× over
Haloacetic acids (HAA5)
Disinfection byproduct
36.2 ppb 0.1 60.0 60 362× over
Haloacetic acids (HAA9)
Disinfection byproduct
16.5 ppb 0.06 276× over
Total trihalomethanes (TTHMs)
Disinfection byproduct
35.1 ppb 0.15 80.0 100 234× over
Dibromoacetic acid
Disinfection byproduct
4.11 ppb 0.03 137× over
Bromodichloromethane
Disinfection byproduct
7.53 ppb 0.06 125× over
Arsenic
Heavy metal
0.47 ppb 0.004 10.0 10 10 0.004 118× over
Dibromochloromethane
Disinfection byproduct
10.1 ppb 0.1 101× over
Chromium (hexavalent)
Heavy metal
1.39 ppb 0.02 69× over
Perfluorononanoic acid (PFNA)
PFAS
0.376 ppt 0.006 10.0 63× over
Trichloroacetic acid
Disinfection byproduct
5.08 ppb 0.1 51× over
Dichloroacetic acid
Disinfection byproduct
7.86 ppb 0.2 39× over
Chloroform
Disinfection byproduct
9.93 ppb 0.4 25× over
Nitrate
Inorganic
3.33 ppm 0.14 10.0 11.3 11.3 10 24× over
Nitrate and nitrite
Inorganic
2.61 ppm 0.14 10.0 11.3 11.3 10 19× over
Bromoform
Disinfection byproduct
7.56 ppb 0.5 15× over
Perfluorooctane sulfonate (PFOS)
PFAS
1.77 ppt 0.3 4.0 100 100 1 5.9× over
Radium, combined (-226 and -228)
Radiological
0.12 pCi/L 0.05 5.0 2.5× over
Perfluorooctanoic acid (PFOA)
PFAS
0.171 ppt 0.09 4.0 100 100 0.007 1.9× over
Uranium
Radiological
0.69 pCi/L 0.43 20.0 30 30 0.43 1.6× over
Chlorate
Disinfection byproduct
113.9 ppb 210.0 Below guideline
Barium
Heavy metal
127.6 ppb 700.0 2000.0 1300 2000 Below guideline
Vanadium
Other
2.66 ppb 21.0 Below guideline
Bromochloromethane
Other
0.00458 ppb 0.06 Below guideline
1,1,2-Trichloroethane
Other
0.0199 ppb 0.3 5.0 Below guideline
1,2,3-Trichloropropane
Other
2.9e-05 ppb 0.0007 Below guideline
Manganese
Heavy metal
2.96 ppb 100.0 50 80 Below guideline
1,4-Dioxane
Semi-volatile organic compound
0.01 ppb 0.35 50 1 Below guideline
Molybdenum
Other
0.741 ppb 40.0 Below guideline
Aluminum
Heavy metal
7.47 ppb 600.0 200 600 Below guideline
Monobromoacetic acid
Disinfection byproduct
0.163 ppb 25.0 Below guideline
Monochloroacetic acid
Disinfection byproduct
0.325 ppb 53.0 Below guideline
Selenium
Heavy metal
0.0817 ppb 30.0 50.0 20 40 30 Below guideline
Perfluorobutanoic Acid (PFBA)
PFAS
0.429 ppt 1000.0 Below guideline
Perfluorobutane sulfonate (PFBS)
PFAS
0.855 ppt 2000.0 Below guideline
Strontium
Radiological
0.294 ppb 1500.0 Below guideline
Perfluorohexanoic Acid (PFHxA)
PFAS
0.095 ppt 1000.0 Below guideline
Perfluoropentanoic Acid (PFPeA)
PFAS
0.027 ppt 1000.0 Below guideline
1,1-Dichloroethane
Volatile organic compound
7.6e-05 ppb 3.0 Below guideline
Perfluoroheptanoic acid (PFHPA)
PFAS
0.01 ppt 1000.0 Below guideline
1,1,1-Trichloroethane
Other
0.0625 ppb 200.0 Below guideline
1,1-Dichloroethylene
Volatile organic compound
0.0355 ppb 7.0 Below guideline
Asbestos
Other
0.02 7.0 Below guideline
Fluoride
Inorganic
0.0805 ppm 4.0 1.5 1.5 Below guideline
Lithium
Other
1.18 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 (4th ed.), California OEHHA PHGs, EWG Tap Water Database.

SAN JOSE WATER service area

This water system serves 1 community in Santa Clara County, California. Click any city for its dedicated tap water quality page.

About this water system

Public Water System ID
CA4310011
Owner type
Private
Source water
Surface water
Service connections
237,130
Service area
SAN JOSE, Santa Clara County, California