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CITY OF SEGUIN

PWS ID: TX0940002 · SEGUIN, Texas 78156-0591

CITY OF SEGUIN serves 32,736 people in SEGUIN, Texas using Surface Water water sources. It has 57 recorded EPA violations, including 53 health-based violations. PFAS "forever chemicals" were detected in UCMR5 testing (3 compounds found).

Water Quality Snapshot: CITY OF SEGUIN

CITY OF SEGUIN is a local-owned community water system that delivers drinking water to 32,736 residents in SEGUIN, Texas (Guadalupe County) through 10,912 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 57 total violations for this system , of which 53 (93%) are health-based — meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 1 monitoring and reporting violations are on file. The most recent violation on record dates to 2024.

The most frequently cited contaminant at this system is Interim Enhanced Surface Water Treatment Rule, recorded in 20 violations (TT, health-based). Under EPA's UCMR5 PFAS monitoring program, 3 PFAS compounds were detected in samples collected from this system, with a maximum reported concentration of 18.6 ppt. PFAS are persistent synthetic chemicals linked to health effects at very low exposure levels.

Across Texas, EPA tracks 7,351 public water systems serving 33,253,313 people, with 746,210 cumulative violations and 162,945 health-based violations on record. About 90% of systems in the state carry at least one violation, and state-wide the average per system is 101.5 violations. CITY OF SEGUIN's 57 violations sit below the Texas average. Statewide, 1,068 of 1,147 UCMR5-tested systems have reported PFAS detections (93.1%). All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

PFAS Detected

3 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.

Population Served
32,736
Total Violations
57
Health-Based Violations
53
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Local
Connections
10,912
County
Guadalupe
School/Daycare
No
MCL Violations
20
Monitoring Violations
1
Treatment Tech Violations
33

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Interim Enhanced Surface Water Treatment Rule TT 20 2004
TTHM MCL 16 2024
Surface Water Treatment Rule TT 13 2004
Total Haloacetic Acids (HAA5) MCL 4 2015
Lead and Copper Rule MR 1 2013

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 9 of 179 samples detected PFAS.

Contaminant Date Result MRL Status
ADONA 9/12/2024 <0.003 µg/L 0.003 µg/L Not Detected
HFPO-DA 9/12/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFBA 9/12/2024 <0.005 µg/L 0.005 µg/L Not Detected
6:2 FTS 9/12/2024 <0.005 µg/L 0.005 µg/L Not Detected
4:2 FTS 9/12/2024 <0.003 µg/L 0.003 µg/L Not Detected
8:2 FTS 9/12/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFHpS 9/12/2024 <0.003 µg/L 0.003 µg/L Not Detected
NFDHA 9/12/2024 <0.02 µg/L 0.02 µg/L Not Detected
9Cl-PF3ONS 9/12/2024 <0.002 µg/L 0.002 µg/L Not Detected
PFHxS 9/12/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFPeA 9/12/2024 0.0037 µg/L 0.003 µg/L Detected
PFPeS 9/12/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFMBA 9/12/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFEESA 9/12/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFMPA 9/12/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFHpA 9/12/2024 <0.003 µg/L 0.003 µg/L Not Detected
NMeFOSAA 9/12/2024 <0.006 µg/L 0.006 µg/L Not Detected
NEtFOSAA 9/12/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFTrDA 9/12/2024 <0.007 µg/L 0.007 µg/L Not Detected
PFTA 9/12/2024 <0.008 µg/L 0.008 µg/L Not Detected
PFOS 9/12/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFBS 9/12/2024 <0.003 µg/L 0.003 µg/L Not Detected
11Cl-PF3OUdS 9/12/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFNA 9/12/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFOA 9/12/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFDA 9/12/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFDoA 9/12/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFHxA 9/12/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFUnA 9/12/2024 <0.002 µg/L 0.002 µg/L Not Detected
lithium 9/12/2024 <9 µg/L 9 µg/L Not Detected
PFEESA 6/10/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFHxS 6/10/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFHpA 6/10/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFBS 6/10/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFHpS 6/10/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFPeS 6/10/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFNA 6/10/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFMBA 6/10/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFPeA 6/10/2024 0.0039 µg/L 0.003 µg/L Detected
PFMPA 6/10/2024 <0.004 µg/L 0.004 µg/L Not Detected
lithium 6/10/2024 <9 µg/L 9 µg/L Not Detected
PFTrDA 6/10/2024 <0.007 µg/L 0.007 µg/L Not Detected
NEtFOSAA 6/10/2024 <0.005 µg/L 0.005 µg/L Not Detected
NMeFOSAA 6/10/2024 <0.006 µg/L 0.006 µg/L Not Detected
NFDHA 6/10/2024 <0.02 µg/L 0.02 µg/L Not Detected
HFPO-DA 6/10/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFTA 6/10/2024 <0.008 µg/L 0.008 µg/L Not Detected
PFOS 6/10/2024 <0.004 µg/L 0.004 µg/L Not Detected
8:2 FTS 6/10/2024 <0.005 µg/L 0.005 µg/L Not Detected
4:2 FTS 6/10/2024 <0.003 µg/L 0.003 µg/L Not Detected

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records — or to file a complaint, request a Consumer Confidence Report, or check current monitoring status — go directly to the federal and state regulators that enforce the Safe Drinking Water Act for CITY OF SEGUIN.

Federal Source of Truth

EPA SDWIS — Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID TX0940002 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Texas Drinking Water Authority

Texas Commission on Environmental Quality (TCEQ) — Drinking Water Watch is the primacy agency that licenses and inspects CITY OF SEGUIN under EPA-delegated authority.

Open TX regulator portal

Source: Texas Commission on Environmental Quality (TCEQ) — Drinking Water Watch

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2024 TTHM MCL 16 SDWIS / TX0940002 / 2950
2015 Total Haloacetic Acids (HAA5) MCL 4 SDWIS / TX0940002 / 2456
2013 Lead and Copper Rule MR 1 SDWIS / TX0940002 / 5000
2004 Interim Enhanced Surface Water Treatment Rule TT 20 SDWIS / TX0940002 / 0300
2004 Surface Water Treatment Rule TT 13 SDWIS / TX0940002 / 0200

How CITY OF SEGUIN Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric CITY OF SEGUIN Texas avg Federal benchmark
Total violations 57 101.5 SDWA compliance — any non-zero count is a recorded breach
Health-based violations 53 22.2 Indicates a contaminant exceeded a federal MCL
PFAS detection 3 compounds 93.1% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 32,736 4,524 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 7,351 regulated public water systems in Texas.

Federal MCL reference — Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is CITY OF SEGUIN water safe to drink? ▼
CITY OF SEGUIN (PWS ID: TX0940002) has 57 recorded violations in the EPA SDWIS database. PFAS contamination has been detected in UCMR5 testing, with 3 PFAS compounds found. This system serves 32,736 people using Surface Water sources.
How many people does CITY OF SEGUIN serve? ▼
CITY OF SEGUIN serves 32,736 people in SEGUIN, Texas. It is a Local-owned system using Surface Water water sources with 10,912 service connections.
What type of violations does CITY OF SEGUIN have? ▼
CITY OF SEGUIN has 57 total violations: 53 health-based violations (MCL exceedances or treatment failures), 1 monitoring/reporting violations, and 33 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in CITY OF SEGUIN water? ▼
Yes. UCMR5 testing detected 3 PFAS compounds in CITY OF SEGUIN's water supply: PFPeA, lithium, PFBA. PFAS are persistent "forever chemicals" that do not break down in the environment.
What water source does CITY OF SEGUIN use? ▼
CITY OF SEGUIN uses Surface Water as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.

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Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. PFAS data from EPA UCMR5 monitoring program (2023-2025). This data is provided for informational purposes only.

Read our methodology — how this data is sourced, computed, and verified.

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Data sourced from $official public datasets. See our methodology for details. Retrieved and formatted by Kiznis Studio Editorial