San Antonio Drinking Water Quality
What's Really in Your Tap Water?
San Antonio tap water meets EPA standards, though there are a few things worth knowing. At 314 ppm (18.4 gpg), the water is quite hard — you may notice mineral buildup on fixtures. Lead levels test well below the EPA action level. PFAS chemicals were detected but are within EPA limits. No violations have been recorded in the past 3 years.
Generally Safe
Minor compliance issues
18.4 GPG hardness
Lead
Below EPA action level
EPA action level: 15 ppb
Hardness
Very Hard water
US Average: 100 ppm
Is San Antonio Tap Water Safe to Drink?
San Antonio tap water meets EPA health standards, with some contaminants worth monitoring.
14 contaminants were tested in San Antonio's water. 12 were detected — all within EPA limits.
PFAS "Forever Chemicals" — 3 PFAS compounds detected, all within current EPA limits. Highest: PFBA at 7.5 ppt.
Metals — 2 contaminants detected, all within EPA limits. Highest: Selenium at 4.2 ppb (8% of EPA limit).
Disinfection Byproducts — 2 contaminants detected, all within EPA limits. Highest: Total Trihalomethanes (TTHM) at 33 ppb (41% of EPA limit).
Radioactive Contaminants — 1 contaminant detected, all within EPA limits. Highest: Combined Radium 226/228 at 1.82 pCi/L (36% of EPA limit).
Inorganic Chemicals — 2 contaminants detected, all within EPA limits. Highest: Nitrate (as N) at 2 ppm (20% of EPA limit).
The data below shows test results from 1 water utility serving 2.1M people in the San Antonio area.
Based on publicly available data from SAWS / Web Sources (2024). Water quality can vary by location, building plumbing, and over time. This assessment reflects compliance with federal EPA standards and is not medical advice.
Do I Need a Water Filter?
PFAS chemicals were detected in San Antonio water, though within current EPA limits. An activated carbon or reverse osmosis filter can further reduce PFAS exposure. With very hard water (314 ppm), a water softener can reduce scale buildup in pipes, appliances, and water heaters.
How Hard is San Antonio Water?
314 ppm
18.4 grains per gallon
Very hard water causes significant mineral buildup. A water softener is recommended.
Impact on Your Home
Shower
Dries out skin & hair
Kitchen
Heavy mineral deposits
Laundry
Stiff, dingy clothes
Appliances
Significant scale
Regional Comparison
Values in ppm (mg/L as CaCO₃)
Do I Need a Water Softener?
At 314 ppm, San Antonio has very hard water. A water softener can help prevent scale buildup in water heaters, dishwashers, and pipes. According to the Water Quality Research Foundation, hard water can reduce appliance efficiency and increase energy costs. A whole-house water softener or salt-free conditioner can help.
Range: 257–342 ppm
Based on 101 samples from SAWS / Web Sources (2024)
Your pipes tell a different story
The data above shows what leaves the treatment plant—not what comes out of your faucet. Old pipes, lead solder, and building plumbing can add contaminants the city never tests for. Know exactly what's in your San Antonio tap water.
Home test kits detect lead, bacteria, pesticides, and 100+ other contaminants. Results in 5-10 business days from certified labs.
Lead & Contaminants
Understanding lead levels and water quality violations in San Antonio
Lead Test Results
90th Percentile Lead Level
1.6 ppb
San Antonio lead levels are well below the EPA action level.
Regular testing is still recommended, as lead can enter water through household plumbing.
Last sampled: 2024-12-31
About Lead in Drinking Water
What is Lead in Water?
According to the EPA, lead is a toxic metal that can dissolve into drinking water from older pipes, solder, and fixtures. It's invisible, tasteless, and odorless, making testing the only way to detect it. The EPA has set an action level of 15 ppb and states there is no safe level of lead exposure.
Potential Health Effects
According to the CDC: developmental delays, learning difficulties, lower IQ, behavioral issues
According to the EPA: high blood pressure, kidney damage, reproductive issues
How to Reduce Exposure
- •Run water for 30 seconds to 2 minutes before drinking, especially in the morning
- •Use cold water for cooking and drinking (hot water dissolves more lead)
- •Install a NSF-certified filter designed to remove lead
- •Test your water, especially if your home was built before 1986
PFAS “Forever Chemicals”
PFAS detected but within current EPA limits
PFAS are synthetic chemicals that don't break down in the environment. Levels are within current EPA maximum contaminant levels.
Total Trihalomethanes (TTHM)
41% of EPA limit
Range: 0–52.9 ppb
Combined Radium 226/228
36% of EPA limit
Range: 1.33–1.82 pCi/L
Chlorine Free
35% of EPA limit
Range: 0.14–6.4 ppm
Nitrate (as N)
20% of EPA limit
Range: 0–2.51 ppm
Other Detected Contaminants
14 contaminants detected
| Contaminant | Your Water | Limit (MCL) | Status |
|---|---|---|---|
Fluoride | 0.4 ppm Range: 0.15-3.31 Range reflects natural variation across Edwards Aquifer wells | 4 ppm Goal: 4 ppm | Safe 10% of limit |
Nitrate (as N) | 2 ppm Range: 0-2.51 | 10 ppm Goal: 10 ppm | Safe 20% of limit |
Barium | 0.112 ppm Range: 0.0395-0.0918 | 2 ppm Goal: 2 ppm | Safe 6% of limit |
Selenium | 4.2 ppb Range: 0-4.2 | 50 ppb Goal: 50 ppb | Safe 8% of limit |
Total Trihalomethanes (TTHM) | 33 ppb Range: 0-52.9 Highest LRAA | 80 ppb | Safe 41% of limit |
Haloacetic Acids (HAA5) | 8 ppb Range: 0-12.7 Highest LRAA | 60 ppb | Safe 13% of limit |
Chlorine Free | 1.41 ppm Range: 0.14-6.4 Max 6.40 ppm exceeds MRDL of 4 in some samples | 4 ppm | Safe 35% of limit |
Combined Radium 226/228 | 1.82 pCi/L Range: 1.33-1.82 | 5 pCi/L 0 | Safe 36% of limit |
PFPEA | 3.2 ppt Range: 0-3.2 UCMR5 - 1/71 samples detected | N/A | Safe |
PFBA | 7.5 ppt Range: 0-9.2 UCMR5 - 3/71 samples detected | N/A | Safe |
PFBS | 3.75 ppt Range: 0-3.8 UCMR5 - 2/71 samples detected | N/A | Safe |
PFOA | 0 ppt Range: 0-0 ND - UCMR5 - 0/71 samples detected | 4 ppt 0 | Safe |
PFOS | 0 ppt Range: 0-0 ND - UCMR5 - 0/71 samples detected | 4 ppt 0 | Safe |
PFPEA | 3.2 ppt Range: 0-3.2 UCMR5 - 1/71 samples detected | N/A | Safe |
MCL = Maximum Contaminant Level (EPA legal limit)
EPA Compliance History
Excellent Record
No violations in past 3 yearsThis utility has maintained full EPA compliance. No action needed, but regular home testing is still recommended.
3-Year Violation Summary
0
Total Violations
0
Health-Related
0
Administrative
Health-Related Violations
Contaminant exceeded EPA maximum contaminant levels. The EPA recommends considering certified filtration.
Administrative Violations
Missed testing deadlines or reporting. Does not indicate water quality issues.
Who Provides San Antonio's Water?
Utility Name
SAN ANTONIO WATER SYSTEM
EPA System ID (PWSID)
TX0150018
Primary Water Source
Surface Water
Population Served
2.1M
Frequently Asked Questions
Common questions about San Antonio tap water quality
Nearby Cities in Texas
Houston
Moderate water
Dallas
Hard water
Austin
Very Hard water
Fort Worth
Hard water
El Paso
Very Hard water
Arlington
Hard water
This data is for informational purposes only. Water quality can vary by neighborhood and building. For official reports, contact your local water utility or the EPA. Learn about our methodology
Data source: SAWS / Web Sources (2024) • View report