Water Quality Report · Updated May 12, 2026
SAN ANTONIO WATER SYSTEM
SAN ANTONIO WATER SYSTEM delivers tap water graded C (67/100) by TapWaterSafety.org. The utility serves approximately 2,113,151 residents in SAN ANTONIO, Texas using surface water (purchased). The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline; Bromochloroacetic acid significantly above health guideline. For questions, the utility can be reached at 210-233-3536.
Is SAN ANTONIO tap water safe to drink?
SAN ANTONIO WATER SYSTEM 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 2,113,151 residents in SAN ANTONIO, drawing from surface water (purchased).
Public testing data identifies 15 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA9), Total trihalomethanes (TTHMs), Bromochloroacetic acid, Dibromoacetic acid, Bromodichloromethane, Haloacetic acids (HAA5), Dibromochloromethane, Nitrate and nitrite, Dichloroacetic acid, Nitrate, Chloroform, Chromium (hexavalent), Radium, combined (-226 and -228), Bromoform, Trichloroacetic acid. 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.
Quick actions for SAN ANTONIO residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for SAN ANTONIO WATER SYSTEM.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 9.67 ppb, 161x above the EWG health guideline of 0.06 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 22.9 ppb, 152x above the EWG health guideline of 0.15 ppb.
Bromochloroacetic acid significantly above health guideline
Moderate concernBromochloroacetic acid detected at 2.12 ppb, 106x above the EWG health guideline of 0.02 ppb.
Contact SAN ANTONIO WATER SYSTEM
Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.
General Contact
Treatment Plant
Recommended water filters for SAN ANTONIO
Filters matched to the specific contaminants in this water supply.
Carbon block (NSF/ANSI 42 + 53)
$40-$750Activated carbon is highly effective for disinfection byproducts like TTHM and HAA5.
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 →
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 |
9.67 ppb | 0.06 | — | — | — | — | — | 161× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
22.9 ppb | 0.15 | 80.0 | 100 | — | — | — | 152× over |
| Bromochloroacetic acid Disinfection byproduct |
2.12 ppb | 0.02 | — | — | — | — | — | 106× over |
| Dibromoacetic acid Disinfection byproduct |
2.41 ppb | 0.03 | — | — | — | — | — | 80× over |
| Bromodichloromethane Disinfection byproduct |
4.42 ppb | 0.06 | — | — | — | — | — | 74× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
5.76 ppb | 0.1 | 60.0 | 60 | — | — | — | 58× over |
| Dibromochloromethane Disinfection byproduct |
5.55 ppb | 0.1 | — | — | — | — | — | 55× over |
| Nitrate and nitrite Inorganic |
2.01 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 14× over |
| Dichloroacetic acid Disinfection byproduct |
2.05 ppb | 0.2 | — | — | — | — | — | 10× over |
| Nitrate Inorganic |
1.42 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 10× over |
| Chloroform Disinfection byproduct |
2.82 ppb | 0.4 | — | — | — | — | — | 7.0× over |
| Chromium (hexavalent) Heavy metal |
0.136 ppb | 0.02 | — | — | — | — | — | 6.8× over |
| Radium, combined (-226 and -228) Radiological |
0.34 pCi/L | 0.05 | 5.0 | — | — | — | — | 6.8× over |
| Bromoform Disinfection byproduct |
2.95 ppb | 0.5 | — | — | — | — | — | 5.9× over |
| Trichloroacetic acid Disinfection byproduct |
0.428 ppb | 0.1 | — | — | — | — | — | 4.3× over |
| Thallium Heavy metal |
0.05 ppb | 0.1 | 2.0 | — | — | — | — | Below guideline |
| Uranium Radiological |
0.14 pCi/L | 0.43 | 20.0 | 30 | 30 | 0.43 | — | Below guideline |
| Vanadium Other |
2.72 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
62.0 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Chlorate Disinfection byproduct |
6.27 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Molybdenum Other |
1.04 ppb | 40.0 | — | — | — | — | — | Below guideline |
| 1,4-Dioxane Semi-volatile organic compound |
0.00829 ppb | 0.35 | — | — | 50 | 1 | — | Below guideline |
| Selenium Heavy metal |
0.1 ppb | 30.0 | 50.0 | 20 | 40 | 30 | — | Below guideline |
| Manganese Heavy metal |
0.299 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
0.0921 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.0277 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.806 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Perfluorobutanoic Acid (PFBA) PFAS |
0.536 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Cobalt Other |
0.0069 ppb | 70.0 | — | — | — | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA) PFAS |
0.076 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
0.088 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Xylenes (total) Volatile organic compound |
0.0123 ppb | 1800.0 | 10000.0 | — | — | — | — | Below guideline |
| 2-methyl-1-propene Other |
5.0 ppb | — | — | — | — | — | — | Below guideline |
| Chromium (total) Heavy metal |
0.243 ppb | — | 100.0 | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.426 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Hexadecanoic acid Other |
3.91 ppb | — | — | — | — | — | — | Below guideline |
| Lithium Other |
9.45 ppb | — | — | — | — | — | — | Below guideline |
| Octadecanoic acid Other |
6.15 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.
SAN ANTONIO WATER SYSTEM service area
This water system serves 1 community in Bexar County, Texas. Click any city for its dedicated tap water quality page.
Find the right filter for SAN ANTONIO water
Browse filter categories by water-quality concern. Each option below is NSF-certified for the matched contaminant type.