Drinking water quality · 2023
· Verified
What's in San Antonio, TX tap water
16 contaminants were measured in the San Antonio, TX water system's 2023 annual report. Each is shown below against its federal limit — 3 sit at or above that limit.
- Reporting year
- 2023
- Contaminants measured
- 16
- Over federal limit
- 3
- Approaching the limit
- 1
- Worst contaminant
- PFBA
- Service area
- TX
PFAS — EPA UCMR5 (2023–2025)
4 PFAS compounds detected in San Antonio, TX
The EPA finalized the first-ever federal drinking-water limits for six PFAS compounds in April 2024. These numbers come straight from EPA's UCMR5 lab dataset — every U.S. system serving more than 3,300 people tested every PFAS sample at an entry point to its distribution system. PFAS not listed below were either tested and not detected, or not yet sampled.
Lithium
● Detected (no federal limit)below national p90 (76.59999999999991 mg/L across detecting U.S. systems)
PFBA
● Detected (no federal limit)near national p90 (18 ng/L across detecting U.S. systems)
PFPeA
● Detected (no federal limit)below national p90 (15.95999999999999 ng/L across detecting U.S. systems)
PFBS
● Detected (no federal limit)below national p90 (13.909999999999979 ng/L across detecting U.S. systems)
Where your water comes from · EPA SDWIS
San Antonio, TX's drinking water comes from ground water, drawn from 181 sources.
Source
- ASR · 29
- MISSION · 8
- NACO · 7
- BASIN · 6
- + 93 more
Treatment
- PLANT - FAC 1 / 411 CARLISLE (SOUTHSIDE)
- PLANT - FAC 5 6019 ZARZAMORA (SOUTHSIDE)
- PLANT - 3019 LA ROSA (SOUTHSIDE)
- + 61 more
Distribution
Also buys water from GBRA WESTERN CANYON WATER SUPPLY, WATER EXPLORATION STEIN ROGER WELL FIELD, and 4 more.
Historical readings · EPA Six-Year Review (2012–2019)
3 contaminants historically over EPA limits in San Antonio, TX
Every U.S. public water system reports compliance-monitoring data to EPA. The Six-Year Review releases the 2012–2019 window as a single dataset — here's what your system reported, year by year. Values shown are the highest detection per analyte per year, compared to the federal MCL.
| Contaminant | Worst detection | EPA limit | Years (2012–2019) |
|---|---|---|---|
GROSS BETA worst: 2017 | 11.7 mrem/yr 2.9× | 4 mrem/yr | '12'13'14'17 |
TTHM worst: 2012 | 0.106 mg/L 1.3× | 0.08 mg/L | '12'13'14'15'16'17'18'19 |
DEHP worst: 2018 | 0.0077 mg/L 1.3× | 0.006 mg/L | '16'17'18 |
CADMIUM worst: 2016 | 0.0034 mg/L within above national p90 | 0.005 mg/L | '16 |
HAA5 worst: 2015 | 0.0346 mg/L within | 0.06 mg/L | '12'13'14'15'16'17'18'19 |
RADIUM 226 228 worst: 2017 | 2.61 pCi/L within near national p90 | 5 pCi/L | '12'13'14'17'19 |
GROSS ALPHA worst: 2017 | 5.3 pCi/L within | 15 pCi/L | '14'16'17'19 |
NITRATE worst: 2018 | 3.14 mg/L within | 10 mg/L | '12'13'14'15'16'17'18'19 |
NITRATE NITRITE worst: 2019 | 2.68 mg/L within | 10 mg/L | '12'13'14'15'17'19 |
DICHLOROMETHANE worst: 2014 | 0.0013 mg/L within | 0.005 mg/L | '14 |
FLUORIDE worst: 2014 | 0.95 mg/L within | 4 mg/L | '12'13'14'15'16'17'18'19 |
PCE worst: 2014 | 0.001 mg/L within | 0.005 mg/L | '12'13'14'15'18 |
BARIUM worst: 2017 | 0.199 mg/L within near national p90 | 2 mg/L | '12'13'14'16'17'18'19 |
SELENIUM worst: 2019 | 0.0045 mg/L within | 0.05 mg/L | '12'16'17'19 |
CHROMIUM worst: 2012 | 0.00415 mg/L within below national p90 | 0.1 mg/L | '12 |
TWOFOURD worst: 2018 | 0.0001 mg/L within below national p90 | 0.07 mg/L | '18 |
ETHYLBENZENE worst: 2014 | 0.0007 mg/L within | 0.7 mg/L | '12'14 |
XYLENES TOTAL worst: 2014 | 0.0039 mg/L within | 10 mg/L | '12'13'14'15'16'17'18'19 |
URANIUM worst: 2016 | 0.0013 ug/L within below national p90 | 30 ug/L | '16'17'19 |
COPPER worst: 2012 | 0.349 mg/L below national p90 | — | '12'13'14'15'16'17'18 |
LEAD worst: 2012 | 0.00675 mg/L | — | '12'14'15'16'17'18 |
DBAA worst: 2012 | 0.0086 mg/L | — | '12'13'14'15'16'17'18'19 |
DCAA worst: 2012 | 0.0099 mg/L | — | '12'13'14'15'16'17'18'19 |
MBAA worst: 2012 | 0.0018 mg/L | — | '12'13'14'15'17 |
MCAA worst: 2012 | 0.003 mg/L | — | '12'15'16'17'18'19 |
TCAA worst: 2012 | 0.0025 mg/L | — | '12'13'14'15'16'17'18'19 |
BROMODICHLOROMETHANE worst: 2012 | 0.0315 mg/L | — | '12'13'14'15'16'17'18'19 |
BROMOFORM worst: 2012 | 0.0146 mg/L | — | '12'13'14'15'16'17'18'19 |
CHLOROFORM worst: 2012 | 0.0261 mg/L | — | '12'13'14'15'16'17'18'19 |
DIBROMOCHLOROMETHANE worst: 2012 | 0.0341 mg/L | — | '12'13'14'15'16'17'18'19 |
Disinfectants
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ChlorineA disinfectant added to drinking water to kill bacteria and viruses. | 1.47 mg/LAverageSystem-wide | 4 mg/LMRDL | Within the limit |
Microbial
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Total ColiformA group of bacteria used as an indicator of overall water-system sanitation. | 0.5Highest single sampleNo. of Positive | 0MCLG | Detected — no federal limit |
+By source (2)— No. of Positive, Total No. of Positive E. Coli or Fecal
| |||
Radionuclides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Combined RadiumCombined radium-226 and radium-228 — naturally occurring radioactive elements. | 1.33–1.82 pCi/LRangeConcentration Range Found | 0 pCi/LMCLG | Detected — no federal limit |
People also ask about San Antonio, TX's water
+Is San Antonio, TX tap water safe to drink in 2023?
The 2023 Consumer Confidence Report for the San Antonio, TX water utility lists 3 contaminants at or above the federal limit: PFBA, Lithium, and Perfluoropentanoic acid. Whether that means the water is "unsafe" depends on which contaminant, how long the exposure, and individual health factors. The table on this page shows the measured value, the federal threshold, and the regulated statistic used for compliance.
+What contaminants are in San Antonio, TX tap water?
16 contaminants were measured in San Antonio, TX's 2023 Consumer Confidence Report, spanning metals, radionuclides, and disinfection byproducts. 16 have an enforceable federal limit; the rest are detected but unregulated. Every measured value, in the utility's own units, is on this page.
+Which contaminants exceed federal limits in San Antonio, TX tap water?
3 contaminants in San Antonio, TX's 2023 report sit at or above the federal limit: PFBA (1.5× the limit); Lithium (1.4× the limit); Perfluoropentanoic acid (1.1× the limit). The EPA enforces these limits against the regulated reporting statistic — typically a running annual average or 90th percentile — not a one-off sample spike.
+What is the worst contaminant in San Antonio, TX tap water?
The contaminant with the highest measured value relative to its federal limit in the 2023 report is PFBA, at 1.5× the federal threshold. It belongs to the pfas ("forever chemicals") family of contaminants.
+Are any contaminants in San Antonio, TX tap water approaching the federal limit?
One contaminant is between 80% and 100% of the federal limit in this report: Fluoride. Approaching means measured but not in violation — a margin that can close quickly if conditions change.
+Where does the data on this page come from?
Every value is transcribed from San Antonio, TX's 2023 Consumer Confidence Report — the annual drinking-water report every U.S. public water utility is required by federal law to publish. The original source document is archived and viewable on this site. A water-quality report covers an entire service area, not a single address.
+How often is San Antonio, TX's water quality data updated?
Each U.S. public water utility publishes one Consumer Confidence Report per year, covering the prior calendar year's measurements. This page reflects the 2023 report; a new report will replace it once the utility publishes its next annual update.