Haloacetic Acids
Approaching LimitDetected level
38.6554 ug/L
0%EPA Limit (60 ug/L)
64% of EPA limit
Health effects: Disinfection byproducts associated with increased cancer risk and potential reproductive effects.
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Tap Water Safety Report for Santa Clara, California
Santa Clara, California tap water scored 52/100 (D) based on EPA data. Multiple contaminants are at concerning levels. A water filter is recommended, especially for children and pregnant women.
Overall Score
52/100
Grade: D
Contaminants Tested
9
All within limits
EPA Violations
8
All resolved
Water Source
surface
Surface water
Population Served
125,268
residents
Water Systems
1
serving this area
1 contaminant(s) are approaching EPA limits and should be monitored.
Detected level
38.6554 ug/L
64% of EPA limit
Health effects: Disinfection byproducts associated with increased cancer risk and potential reproductive effects.
Based on Santa Clara's water quality data, here are our specific recommendations:
Santa Clara's water has multiple contaminants at concerning levels. An under-sink reverse osmosis system or a certified multi-stage filter is strongly recommended for drinking and cooking water.
Babies and young children are especially vulnerable to water contaminants. Use filtered or bottled water for mixing formula and for drinking water until filtration is installed.
How contaminant levels compare to EPA limits (50% of overall score)
EPA violation history and enforcement actions (30% of overall score)
Water system infrastructure and source quality (20% of overall score)
With a score of 52/100, Santa Clara's tap water has significant quality concerns. We strongly recommend against using unfiltered tap water for babies or young children. Use bottled water or invest in a reverse osmosis filter for any water consumed by children. Infants are especially vulnerable to contaminants like lead and nitrates, which can cause serious developmental and health issues.
Santa Clara's water has been tested for 9 contaminants. None currently exceed EPA maximum contaminant levels. The most notable detections include: Haloacetic Acids (38.6554 ug/L, EPA limit: 60 ug/L — 64% of limit); Lead (0.0069 mg/L, EPA limit: 0.015 mg/L — 46% of limit); Nitrite (0.4173 mg/L, EPA limit: 1 mg/L — 42% of limit); Arsenic (0.0041 mg/L, EPA limit: 0.01 mg/L — 41% of limit); Total Trihalomethanes (31.7279 ug/L, EPA limit: 80 ug/L — 40% of limit). The water system has no active EPA violations. Water quality can vary seasonally and by neighborhood, so home testing provides the most accurate picture for your specific tap.
Absolutely. With a water quality score of 52/100, filtering is strongly recommended in Santa Clara. A reverse osmosis (RO) system is the most effective option, removing up to 99% of contaminants. At minimum, use a certified pitcher filter rated for the specific contaminants found in your water. Multiple contaminants at concerning levels make filtration an important health measure.
Santa Clara's water quality score of 52/100 (D) is 20 points below the national average of 72. The city's water comes from surface water sources like rivers and reservoirs. This indicates significant water quality challenges that the city should work to address. You can see how Santa Clara compares to nearby cities in our state rankings.
Detailed contaminant data, violation history, and water system information for Santa Clara.
Find the best water filter for Santa Clara based on detected contaminants and your budget.
See how Santa Clara compares to other cities across California.
See how Santa Clara ranks among all cities in the US for water quality.
Data Disclaimer
This report is based on publicly available EPA data and water quality test results. Water quality can vary by neighborhood, building age, and season. This information is for educational purposes and should not replace professional water testing. If you have specific health concerns about your water, contact your local water utility or a certified water testing laboratory. Last data update: February 2, 2026.