San Antonio Tap Water

Water provider: San Antonio Water System (San Antonio, TX)

Our recommendation

Mid-range filter recommended

Your water has detectable contaminants worth filtering. A countertop or under-sink carbon block with multi-stage filtration handles what is present here.

See recommended water filters →

What is in the water

Trihalomethanes (THMs)

Detected

Disinfection byproducts formed when chlorine reacts with organic matter. Long-term exposure linked to cancer risk.

Reported: ~25 ppb

Chlorine

Within limits

Added to disinfect water. Generally safe at treatment levels but reacts with organic matter to form disinfection byproducts.

Atrazine

Detected

Agricultural herbicide. Endocrine disruptor. Banned in the EU, still used in the US.

Reported: seasonal

Source

Data from the SAWS Water Quality Report (2023). Last reviewed 2024-11-01.

Note: Contaminant levels vary by address (older plumbing can leach lead even when the source water does not), sampling location, and time of year. The figures above reflect utility-wide averages from the most recent public report. If you have specific health concerns, request a full report from your utility or test your own tap water.

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