Water Quality Report · Updated May 12, 2026

CITY OF SANTA CLARA

Serving 130,746 residents in SANTA CLARA, California .

National rank 66th percentile
California rank 91th percentile
Data confidence Medium
Quick answer

CITY OF SANTA CLARA delivers tap water graded C (67/100) by TapWaterSafety.org. The utility serves approximately 130,746 residents in SANTA CLARA, California using surface water (purchased). The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline. For questions, the utility can be reached at 408-615-2018.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?
130,746
People served
1
City served
24
Contaminants detected
13
Above health guidelines
0
EPA violations (5 yr)

Is SANTA CLARA tap water safe to drink?

CITY OF SANTA CLARA delivers tap water that earns a grade of C (67/100) from TapWaterSafety.org — an average rating, with several contaminants above health guidelines but generally compliant with US legal limits.

The utility serves 130,746 residents in SANTA CLARA, drawing from surface water (purchased).

Public testing data identifies 13 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA9), Haloacetic acids (HAA5), Total trihalomethanes (TTHMs), Trichloroacetic acid, Chromium (hexavalent), Bromodichloromethane, Dibromoacetic acid, Chloroform, Dichloroacetic acid, Dibromochloromethane, Nitrate, Nitrate and nitrite, Bromoform. 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 CITY OF SANTA CLARA.

Haloacetic acids (HAA9) significantly above health guideline

Moderate concern

Haloacetic acids (HAA9) detected at 23.5 ppb, 392x above the EWG health guideline of 0.06 ppb.

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.

Total trihalomethanes (TTHMs) significantly above health guideline

Moderate concern

Total trihalomethanes (TTHMs) detected at 26.1 ppb, 174x above the EWG health guideline of 0.15 ppb.

Contact CITY OF SANTA CLARA

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

Recommended water filters for SANTA CLARA

Filters matched to the specific contaminants in this water supply.

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 67/100 breaks down across five weighted components. Read the full methodology →

Health Guideline Performance
10 / 40
Legal Compliance
20 / 20
High-Risk Contaminants
20 / 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
Haloacetic acids (HAA9)
Disinfection byproduct
23.5 ppb 0.06 392× over
Haloacetic acids (HAA5)
Disinfection byproduct
36.2 ppb 0.1 60.0 60 362× over
Total trihalomethanes (TTHMs)
Disinfection byproduct
26.1 ppb 0.15 80.0 100 174× over
Trichloroacetic acid
Disinfection byproduct
6.96 ppb 0.1 70× over
Chromium (hexavalent)
Heavy metal
1.34 ppb 0.02 67× over
Bromodichloromethane
Disinfection byproduct
3.96 ppb 0.06 66× over
Dibromoacetic acid
Disinfection byproduct
1.75 ppb 0.03 58× over
Chloroform
Disinfection byproduct
17.9 ppb 0.4 45× over
Dichloroacetic acid
Disinfection byproduct
8.94 ppb 0.2 45× over
Dibromochloromethane
Disinfection byproduct
4.05 ppb 0.1 40× over
Nitrate
Inorganic
3.69 ppm 0.14 10.0 11.3 11.3 10 26× over
Nitrate and nitrite
Inorganic
3.65 ppm 0.14 10.0 11.3 11.3 10 26× over
Bromoform
Disinfection byproduct
1.33 ppb 0.5 2.7× over
Chlorate
Disinfection byproduct
86.2 ppb 210.0 Below guideline
Vanadium
Other
3.24 ppb 21.0 Below guideline
Barium
Heavy metal
85.0 ppb 700.0 2000.0 1300 2000 Below guideline
Molybdenum
Other
1.73 ppb 40.0 Below guideline
Monochloroacetic acid
Disinfection byproduct
0.409 ppb 53.0 Below guideline
Monobromoacetic acid
Disinfection byproduct
0.133 ppb 25.0 Below guideline
Manganese
Heavy metal
0.482 ppb 100.0 50 80 Below guideline
Strontium
Radiological
0.31 ppb 1500.0 Below guideline
Chlorodifluoromethane
Other
0.143 ppb Below guideline
Fluoride
Inorganic
0.157 ppm 4.0 1.5 1.5 Below guideline
Lithium
Other
0.952 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.

CITY OF SANTA CLARA 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
CA4310012
Owner type
Local government
Source water
Surface water (purchased)
Service connections
26,113
Service area
SANTA CLARA, Santa Clara County, California