WaterVerge

Is Atascosa, TX Tap Water Safe to Drink?

Graded D, with 18 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

14K residents served 1 water system PWSID: TX0150040
Overall Score
49.1 / 100
Violations
18 active
Last Updated
May 2026
Source
Purchased surface water
#781 of 1067 in Texas Top 84% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
DGRADE
Water Quality Grade
49.1/100
waterverge.com
D 49.1/100

Atascosa, TX — Water Quality Report

Atascosa's drinking water received a grade of D (49.1 out of 100), indicating poor water quality. The city's 1 water system serves approximately 13,905 residents using purchased surface water.

Lead levels were measured at 2.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.

The system has 42 violations on record, including 17 health-based violations. 18 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Atascosa's water

Atascosa ranks #781 out of 1067 cities in Texas for water quality, placing it below average in the state.

The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection.

PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.

The system has seen 29 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
49.1 out of 100 Grade D
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
5.9/45
F
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 2.0 ppb (90th percentile).
Contaminants
16.2/20
B
1 PFAS compound detected.
Compliance
3/10
F
Monitoring and reporting compliance with EPA regulations.
Source Risk
4/5
B
Water source: Purchased surface water.
Water Safety

Is Atascosa, TX water safe to drink?

Concerns Identified

Atascosa's drinking water has significant quality concerns based on EPA testing data. With a grade of D (49.1/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 13,905 residents using surface water (rivers, lakes, or reservoirs).

18
Active Violations
2.0 ppb
Lead (90th %ile)
1 compound
PFAS Detected
9 events
Disaster History

Recent water quality updates for Atascosa

A timeline of significant water quality events, violations, and data updates.

PFAS
1 PFAS "forever chemical" compound detected

Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Atascosa's water quality assessment. Grade: D (49.1/100).

Violation
1 drinking water violation recorded

Contaminants: Lead and Copper Rule.

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Violation
1 drinking water violation recorded

Contaminants: Chlorine.

Disaster
TROPICAL STORMS MARCO AND LAURA

Federal disaster declaration (FEMA DR-3540). Hurricane event — may have impacted local water infrastructure.

Key contaminant findings

Based on the most recent EPA sampling data for Atascosa's water supply.

Lead Within Limits
Detected: 2.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

PFAS (1 compound) Elevated
Detected: Highest: lithium at 13.6000 µg/L Limit: 0.004 µg/L (EPA MCL)

Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.

Violation history

Atascosa's water system has 42 total violations on record, including 17 health-based violations. 18 remain unresolved. 29 violations were issued in the last 5 years.

MROtherMCL
Most recent violations:
Dec 2025 Lead and Copper Rule Open
Jul 2025 Consumer Confidence Rule Open
Apr 2025 Chlorine Resolved
Jan 2025 Chlorine Resolved
Feb 2024 Public Notice Open

Flood & environmental risk

Bexar County has experienced 9 federally declared disasters since 2005. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Medina Rv At La Coste, Medina Rv Nr Macdona, Leon Ck At Sh 90, San Antonio, Leon Ck At Morey Rd, San Antonio, Leon Ck At Sw Military Dr, San Antonio.

TROPICAL STORMS MARCO AND LAURA
Hurricane FEMA DR-3540
HURRICANE HANNA
Hurricane FEMA DR-3530
HURRICANE HARVEY
Hurricane FEMA DR-4332

Where does Atascosa's water come from?

Atascosa's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 1 water system serving approximately 13,905 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include Medina Rv At La Coste (river), Medina Rv Nr Macdona (river), Leon Ck At Sh 90, San Antonio (river), Leon Ck At Morey Rd, San Antonio (river), Leon Ck At Sw Military Dr, San Antonio (river).

What Atascosa residents can do

Install a water filter

Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in Atascosa's water.

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Monitor alerts during storms

Atascosa's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
2.0 ppb
EPA Action Level: 15 ppb · 13% of limit
Safe Level
lithium
PFAS / Forever Chemical
Near MCL
13.6000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
1.3 µg/L
EPA MCL: 60 µg/L · 2% of limit
Within LimitUCMR 4 DataHAA6Br: 2.0 µg/LHAA9: 2.8 µg/L
Manganese
Inorganic
Detected
0.9 µg/L
EPA Secondary MCL: 50 µg/L · 2% of limit
DetectedUCMR 4 Data
Lithium
Inorganic
Detected
13.6 µg/L
State screening level: 60 µg/L · 23% of limit
DetectedNo federal MCLUCMR 5 Data (2023–2025)
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
1
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

42
Total violations
17
Health-based
18
Active / unresolved
Dec 2025
Most recent violation
Compliance Record

Violations & advisories

42 Total
18 Active
17 Health-based
24 Resolved
Violations by category
Radionuclides and Revised Rad Rule
12
Public Notice Rule and Revised PN Rule
10
Stage 1 Disinfectants and Disinfection Byproducts Rule
5
Lead and Copper Rule
4
Nitrate Rule
3
Dec 2025 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2025 Active
Consumer Confidence Rule
Other Violation 0
Feb 2024 Active
Public Notice
Other Violation 0
Feb 2024 Active
Public Notice
Other Violation 0
Apr 2023 Active
Public Notice
Other Violation 0
Apr 2023 Active
Public Notice
Other Violation 0
Mar 2023 Active
Public Notice
Other Violation 0
Nov 2022 Active
Public Notice
Other Violation 0
Jul 2022 Active
Public Notice
Other Violation 0
Jul 2022 Active
Public Notice
Other Violation 0
Jul 2022 Active
Consumer Confidence Rule
Other Violation 0
Jan 2022 Active
Public Notice
Other Violation 0
May 2021 Active
E. COLI
Monitoring & Reporting
Monitoring & Reporting 0
May 2021 Active
Public Notice
Other Violation 0
Oct 2017 Active
E. COLI
Monitoring & Reporting
Monitoring & Reporting 0
Dec 2016 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Dec 2013 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Apr 2025 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2025
Jan 2025 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Showing 20 of 42 violations
Environmental Risk

Drought conditions

D3 — extreme drought

Bexar County is currently in D3 (extreme drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.

14
Weeks at D2+ (current streak)
24.9%
Months in D2+ (last 30y)
14
Weeks at D2+ (last 5y)

Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.

Environmental Risk

Flood & disaster history

9
Declared disasters
Aug 2020
Most recent
Hurricane
Most common type

Bexar County has experienced 9 federally declared disasters since 2005. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Aug 2020
TROPICAL STORMS MARCO AND LAURA
Hurricane FEMA #3540
Jul 2020
HURRICANE HANNA
Hurricane FEMA #3530
Aug 2017
HURRICANE HARVEY
Hurricane FEMA #4332
Jun 2010
TROPICAL STORM ALEX
Hurricane FEMA #3313
Sep 2008
HURRICANE IKE
Hurricane FEMA #3294
Aug 2008
HURRICANE GUSTAV
Hurricane FEMA #3290

Recommended water filters

Based on contaminants detected in Atascosa's water supply, we recommend the following filter types.

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
1 PFAS compound detected

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 2.0 15 ppb Inorganic Safe
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS ND HI µg/L PFAS Not Detected
8:2 FTS ND HI µg/L PFAS Not Detected
9Cl-PF3ONS ND HI µg/L PFAS Not Detected
ADONA ND HI µg/L PFAS Not Detected
HFPO-DA ND 0.01 µg/L PFAS Not Detected
lithium 13.600 HI µg/L PFAS Detected
NEtFOSAA ND HI µg/L PFAS Not Detected
NFDHA ND HI µg/L PFAS Not Detected
NMeFOSAA ND HI µg/L PFAS Not Detected
PFBA ND HI µg/L PFAS Not Detected
PFBS ND HI µg/L PFAS Not Detected
PFDA ND HI µg/L PFAS Not Detected
PFDoA ND HI µg/L PFAS Not Detected
PFEESA ND HI µg/L PFAS Not Detected
PFHpA ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA ND HI µg/L PFAS Not Detected
PFPeS ND HI µg/L PFAS Not Detected
PFTA ND HI µg/L PFAS Not Detected
PFTrDA ND HI µg/L PFAS Not Detected
PFUnA ND HI µg/L PFAS Not Detected
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 2.3 ppb from 1993 (4.3 ppb) to 2025 (2.0 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Purchased Surface Water
Operator
Local Government
Population Served
13,905
Water Systems
1
Water Source

Where Atascosa's water comes from

Purchased Surface Water

Atascosa's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.

Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards.

These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge.

The system is operated by local government ownership and serves approximately 13,905 people through 1 water system.

Local Hydrology

Water bodies near Atascosa

Atascosa is located near 5 notable water bodies. As a surface water system, these water bodies may directly influence the city's drinking water supply.

Medina Rv At La Coste
river
Medina Rv Nr Macdona
river
Leon Ck At Sh 90, San Antonio
river
Leon Ck At Morey Rd, San Antonio
river
Leon Ck At Sw Military Dr, San Antonio
river
Infrastructure

Water systems serving Atascosa

System Name PWSID Population Source
ATASCOSA RURAL WSC TX0150040 13,905 SWP
Regional Comparison

How Atascosa compares

Full Texas rankings →

Atascosa's score of 49.1/100 is on par with the average of 46/100 among major Texas cities. It outscores 7 of 10 nearby cities.

Atascosa (this city)
49.1
Houston
27.8
Austin
31.2
Dallas
36.2
Fort Worth
34.5
Texas avg
46
City Profile

About Atascosa, TX

Wikipedia →

Atascosa is an unincorporated community located in southwestern Bexar County, Texas, United States. According to the Handbook of Texas, the community had a population of 300 in 2000. The community is part of the San Antonio Metropolitan Statistical Area.

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Frequently asked questions

Is Atascosa, TX tap water safe to drink?

Atascosa's water quality earned a grade of D (49.1/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #781 out of 1067 cities tested in Texas.

What contaminants are in Atascosa's water?

Lead was measured at 2.0 ppb (90th percentile). 1 PFAS compound was detected. 42 violations are on record.

How is Atascosa's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Atascosa?

PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.

Where does Atascosa's water come from?

Atascosa's water is sourced from Purchased surface water. The city has 1 water system serving approximately 13,905 residents.

What health violations has Atascosa's water system had?

Atascosa has 17 health-based violations on record. The most recent violation was recorded in December 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 18 violations remain unresolved.

How does Atascosa's water compare to other cities?

Atascosa ranks #781 out of 1067 cities in Texas (better than 27% of state cities) and #13275 out of 15744 cities nationally (16th percentile). The grade of D reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.