Bexar County, Texas has about 2,127,737 residents (Census 2024 estimate) and 42 community water systems in EPA records. The largest local system is San Antonio Water System, serving about 2,643,729 people from surface water.
! 1 of 6 largest systems with health-based violationsPFAS detected at 1 of 6 sampled systemsHardness 256.5–342 mg/L, varies by area
Public-record figures, not a test of your tap. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.
How hard is Bexar County water?
San Antonio Water SystemMeasured (utility report, n/a (FAQ page)) · High confidence
256.5–342 mg/L(varies by area; no single average published)
Public-record figures, not a test of your tap. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.
At this hardness most homes don't need a softener. Confirm with a test strip if you see scale.
Largest water systems in Bexar County
The 6 biggest of 42 community water systems on EPA records for this county. Service areas don't follow county lines; your water bill names your provider.
San Antonio Water System
TX0150018 · serves about 2,643,729 people · Surface water
✓ No health-based violations✓ Lead below action levelPFAS detected (3 types)
Lead 90th percentile: 1.6 ppb (period starting 2022-01-01) Older result. Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).
PFBA: highest sample 9.2 ppt (3 of 91 samples); no federal limit
PFBS: highest sample 3.8 ppt (2 of 91 samples); no individual limit; counted in EPA's PFAS mixture (hazard index) limit
PFPeA: highest sample 3.2 ppt (1 of 91 samples); no federal limit
TX0150116 · serves about 37,563 people · Groundwater
! 1 health-based violation✓ Lead below detection✓ No PFAS detected
Lead 90th percentile: <DL (below the lab detection/reporting limit; reported as 0) (period starting 2026-01-01). Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).
TX0150114 · serves about 20,907 people · Groundwater
✓ No health-based violations✓ Lead below detection✓ No PFAS detected
Lead 90th percentile: <DL (below the lab detection/reporting limit; reported as 0) (period starting 2025-01-01). Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).
Public-record figures, not a test of your tap. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.
A PFAS detection is not a violation. Federal limits (4 ppt for PFOA and PFOS) apply to running annual averages, with compliance required by 2029. In May 2026 EPA proposed extending the PFOA/PFOS deadline to 2031 and removing other PFAS limits; not final as of 2026-10-21.
Test your own tap
These are public records for whole systems. Your home's pipes, fixtures and any private well can change what you drink. A certified lab test or a hardness test strip gives you your own numbers. Then use our PFAS and lead filter selector to see which certifications to look for.
Common questions about Bexar County water
Is tap water in Bexar County safe to drink?
1 of the 6 largest systems here have at least one health-based violation in EPA records since October 2021 (see each system below for status). San Antonio Water System's most recent lead 90th percentile was 1.6 ppb (2022), below the 15 ppb action level. Public records can't guarantee what comes out of your tap, especially with older plumbing, so a home test is the surest check.
How hard is the water in Bexar County?
San Antonio Water System reports hardness from 256.5 to 342 mg/L depending on where you live, with no single system-wide average, so check your area in its report or test your water.
Is there PFAS in Bexar County water?
1 of the 6 sampled systems listed here detected at least one PFAS in EPA's UCMR 5 testing. A detection isn't a violation: federal PFAS limits apply to running annual averages starting in 2029.
Which water system serves my address in Bexar County?
Most homes are served by San Antonio Water System or one of the other systems listed on this page, but service areas don't follow county lines. Your water bill names your provider, and its annual Consumer Confidence Report has the full test results.
Data as of October 21, 2026. Figures are copied from public records and combined with our own calculations; they can be out of date or wrong. Tapped Out isn't affiliated with any utility or the EPA. Written and reviewed by the Tapped Out team. How we calculate · All sources.