Across San Antonio, TX, the overall grade falls in the upper range - a summary score, not a measurement taken at any single tap.

Data: EPA SDWIS, FEMA NFIP, Census ACS

Water Quality in San Antonio

We track home safety signals for 86 ZIP codes in San Antonio, Texas. EPA community-water data is directly mapped for 60 ZIP codes and 36 water systems.

23 of 60 directly mapped ZIP records with reported violation counts (38%) have recorded EPA violations - 562 total, including 130 health-based violations.

Average Home Safety Score: A (89/100)

Water sources: Groundwater, Surface water.

Top Contaminants

Lead Risk

• Average of reported 90th-percentile lead results: 0.0018 mg/L
• 0 of 60 ZIP codes with known status exceed the EPA lead action level
• 49% of housing built before 1986 (when lead solder was banned)
• 12% of housing built before 1950 (when lead pipes were standard)
• Median year built: 1982
• Most common estimated pipe material: Copper
• Lead exposure risk score: 34/100
• Estimated lead service line probability: 14%
• 19 ZIP codes classified as high or very high lead risk

With 49% of homes built before the 1986 lead solder ban, San Antonio residents - especially those in older neighborhoods - should consider testing their tap water for lead. Homes built before 1950 are at the highest risk of having lead service lines.

Housing Age Distribution

733,729 total housing units across 86 ZIP codes:

Flood Risk

FEMA National Flood Insurance Program data for San Antonio:

• 2,159 flood insurance claims on record
• $30,855,979 sum of reported building, contents, and ICC payment components
• 1,517 claims with payment data
• 642 claims without reported payment fields
• $20,340 average reported component sum among claims with payment data
• Dominant rated-zone value in historical claims: X (other)
• 17 of 58 ZIP codes with claim-zone records have an A/V-family dominant rated zone in those claims
• Claim-zone values are historical insurance records, not a complete current FEMA property-map inventory

Radon Risk

86 of 86 ZIP records with known zones are in EPA Radon Zone 3.

The EPA recommends testing all homes regardless of radon zone. County radon zones cannot replace an in-home radon test.

Neighborhoods by Safety Score

Safest Areas

Areas Needing Attention

What San Antonio Residents Can Do

Test Your Water

• Order a certified lab test - home test kits cost $20–50 and cover lead, bacteria, and common contaminants
• Request your utility's CCR (Consumer Confidence Report) - your water provider must publish this annually
• Check your ZIP code - each area in San Antonio has different water systems and risk levels

Filter Your Water

• NSF-certified pitcher filter removes chlorine taste and some contaminants ($20–40)
• NSF 53-certified filter for lead - recommended for homes built before 1986
• Reverse osmosis system removes 95%+ of contaminants including lead, PFAS, and nitrates ($150–400)

Stay Informed

• Visit your ZIP code report for detailed, address-level data
• Sign up for EPA water quality alerts
• Review the annual water quality report from your local utility

All ZIP Codes in San Antonio

• 78201 [A]
• 78202 [A]
• 78203 [A]
• 78204 [A]
• 78205 [A]
• 78206
• 78207 [A]
• 78208 [A]
• 78209 [A] - 8 violations ⚠
• 78210 [A]
• 78211 [A]
• 78212 [A]
• 78213 [A] - 8 violations ⚠
• 78214 [A]
• 78215 [A]
• 78216 [A]
• 78217 [A]
• 78218 [A] - 1 violation
• 78219 [A] - 11 violations ⚠
• 78220 [A]
• 78221 [A]
• 78222 [A]
• 78223 [B] - 10 violations
• 78224 [B] - 30 violations ⚠
• 78225 [A]
• 78226 [A]
• 78227 [A]
• 78228 [A]
• 78229 [A]
• 78230 [A] - 8 violations ⚠
• 78231 [A] - 8 violations ⚠
• 78232 [A]
• 78233 [A] - 5 violations
• 78234 [A] - 3 violations ⚠
• 78235 [A]
• 78237 [A]
• 78238 [B] - 43 violations
• 78239 [A] - 1 violation
• 78240 [B] - 43 violations
• 78241
• 78242 [A]
• 78243
• 78244 [A] - 8 violations
• 78245 [B] - 55 violations ⚠
• 78246
• 78247 [A]
• 78248 [A]
• 78249 [B] - 24 violations ⚠
• 78250 [B] - 43 violations
• 78251 [A]
• 78252 [B] - 30 violations ⚠
• 78253 [B] - 10 violations ⚠
• 78254 [A]
• 78255 [A] - 8 violations ⚠
• 78256 [A]
• 78257 [A]
• 78258 [A]
• 78259 [A]
• 78260 [A]
• 78261 [A]
• 78263 [A] - 5 violations
• 78264 [B] - 31 violations ⚠
• 78265
• 78266 - 169 violations ⚠
• 78268
• 78269
• 78270
• 78278
• 78279
• 78280
• 78283
• 78284
• 78285
• 78286
• 78287
• 78288
• 78289
• 78291
• 78292
• 78293
• 78294
• 78295
• 78296
• 78297
• 78298
• 78299

Frequently Asked Questions

Is the tap water safe to drink in San Antonio, TX?

The Home Safety Score is not a drinking-water grade. San Antonio has an average score of 89/100 (grade A) across 58 ZIP codes with complete current-model evidence. Separately, there are 562 recorded EPA violations across 60 directly mapped ZIP records with reported counts, 130 of which are health-based. Check the specific ZIP and serving utility before drawing a water-safety conclusion.

Does San Antonio have lead in the water?

The average of the reported 90th-percentile lead results across the ZIP codes of San Antonio is 0.0018 mg/L, below the EPA action level of 0.015 mg/L. 0 of 60 ZIP codes with known action-level status are served by a system whose 90th-percentile lead result exceeded the EPA action level. About 49% of housing was built before 1986, when lead solder was banned.

Is San Antonio at risk for flooding?

FEMA data shows 2,159 flood insurance claim records in San Antonio ZIP codes, with an average reported building, contents, and ICC component sum of $20,340 among 1,517 claims with payment data. 642 claims lack reported payment fields and are not counted as zero. Among 58 ZIP codes with historical claim-zone values, 17 have an A/V-family dominant rated zone in those claims. Claim records do not establish current property-level flood risk; check the FEMA map for a specific address.

Are there lead pipes in San Antonio homes?

49% of San Antonio housing was built before 1986, when lead solder was common in plumbing. 12% was built before 1950, when lead pipes were standard. The most common estimated pipe material is Copper. The estimated probability of lead service lines is 14%. We recommend testing your water if your home was built before 1986.

What contaminants have been found in San Antonio water?

The most common contaminants by violation count are Lead and Copper Rule, Long Term 2 Enhanced Surface Water Treatment Rule, Fecal Coliform. Across 60 ZIP codes with directly mapped EPA water data, 23 have recorded EPA violations. Check your ZIP code report for the specific contaminants in your area.

Data Sources

• Water quality: EPA Safe Drinking Water Information System (SDWIS)
• Lead/copper: EPA Lead and Copper Rule sampling data
• Housing age: U.S. Census Bureau American Community Survey
• Flood data: FEMA National Flood Insurance Program
• Lead exposure: Composite risk score based on housing age, water lead levels, and service line estimates
• Radon: EPA Map of Radon Zones

Source reporting periods vary. See each cited source for its publication schedule.

Housing Age Profile

1982

Median Year Built

N/A

Pre-1986 (lead solder era; lead paint banned 1978)

0%

Pre-1970 (Lead Pipes Risk)

Most homes in San Antonio were built after 1986; lead exposure at a tap still depends on its service line and plumbing. Older homes should still be tested.

Source: U.S. Census Bureau ACS B25034.

Protecting Children from Lead in San Antonio

0.0018

mg/L average of reported water-system 90th-percentile lead results (the 0.015 action level applies to each system's result, not to this average)

Why children are most at risk: The CDC states that no safe blood lead level in children has been identified. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.

Available area-level lead records for San Antonio do not determine the lead level at an individual tap. Testing is the only way to confirm your water's lead content.

Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.

Historical Flood-Claim Evidence for San Antonio

2,159

Total FEMA Flood Claims

$20,340

Avg Reported Sum With Payment Data

29%

A/V Share of Claim-Record ZIPs

Historical NFIP data for San Antonio contains 2,159 flood insurance claims. Among claims with payment data, the average reported building, contents, and ICC component sum is $20,340. Among ZIP codes with claim records, 29% have an A- or V-family dominant rated zone recorded in those historical claims. This is not a complete current FEMA property-map inventory.

How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure.

Claim count does not establish current property risk. Check the exact address in FEMA's current map and obtain a property-specific insurance quote when relevant.

Source: historical FEMA National Flood Insurance Program (NFIP) claim records. No current FEMA property-map designation is asserted.