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Public water system record

City of Seguin

Serves Seguin, Guadalupe County, TX · 32,736 people served

Federal records show 1 health-based violation and no monitoring/reporting issues for City of Seguin in the last ten years. The most serious issue in this window was a resolved Total Trihalomethanes (TTHMs) violation.

  • TX0940002
  • SEGUIN
  • TX
  • 32,736 served

System profile

Source water Surface water
ZIP 78156
EPA system ID TX0940002

Verify this system on EPA ECHO →

Health-based violations, last 10 years
1
Resolved
1
Unresolved
0
Any acute record
No
Monitoring issues, last 10 years
0

Key facts

  • City of Seguin draws water from 2 surface water intakes.
  • Highest measured level in the last 10 years: Total Trihalomethanes (TTHMs), 0.083 mg/L, federal limit 0.08 mg/L (at or just above the limit), 2024.
  • Record on file since 1998, with 17 health-based violations before October 19, 2016.
  • Lead pipe inventory: 4 lead and 1,957 unknown out of 10,646 service lines.

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Health-based violations

Since October 2016

Violation data reflects EPA records through March 2026. For the most current status, visit the EPA ECHO database.

Contaminant Rule family Start date Status Acute
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.083 mg/L, federal limit 0.08 mg/L (at or just above the limit)
 220 Oct 1, 2024 Resolved No

Full record since 1998

EPA's records for City of Seguin go back to 1998. Before October 19, 2016 they list 17 health-based violations (16 resolved, 1 archived by EPA without a recorded fix) and 1 monitoring or reporting violation.

Violations that began in Health-based Monitoring and reporting
1990s 2 0
2000s 12 0
2010 to October 18, 2016 3 1
2020s 1 0

Most recent health-based violation before October 19, 2016: Total Trihalomethanes (TTHMs), began April 2016, Resolved.

Show all 17 health-based violations before October 19, 2016
Contaminant Start date Status
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.09 mg/L, federal limit 0.08 mg/L (1.1 times the limit)
 Apr 1, 2016 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.081 mg/L, federal limit 0.08 mg/L (at or just above the limit)
 Jan 1, 2016 Resolved
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.062 mg/L, federal limit 0.06 mg/L (at or just above the limit)
 Oct 1, 2015 Resolved
Interim Enhanced Surface Water Treatment Rule (acute)
Treatment technique failure
 Dec 1, 2004 Resolved
Surface Water Treatment Rule
Treatment technique failure
 Oct 1, 2004 Resolved
Interim Enhanced Surface Water Treatment Rule (acute)
Treatment technique failure
 Sep 1, 2004 Resolved
Surface Water Treatment Rule
Treatment technique failure
 Sep 1, 2004 Resolved
Interim Enhanced Surface Water Treatment Rule (acute)
Treatment technique failure
 Sep 1, 2004 Resolved
Surface Water Treatment Rule
Treatment technique failure
 Aug 1, 2004 Resolved
Surface Water Treatment Rule
Treatment technique failure
 Aug 1, 2004 Resolved
Interim Enhanced Surface Water Treatment Rule (acute)
Treatment technique failure
 Jun 1, 2004 Resolved
Interim Enhanced Surface Water Treatment Rule (acute)
Treatment technique failure
 Jan 1, 2004 Resolved
Interim Enhanced Surface Water Treatment Rule (acute)
Treatment technique failure
 Dec 1, 2003 Resolved
Interim Enhanced Surface Water Treatment Rule (acute)
Treatment technique failure
 Jan 1, 2003 Resolved
Interim Enhanced Surface Water Treatment Rule (acute)
Treatment technique failure
 Jan 1, 2003 Resolved
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
 Jan 10, 1999 Archived
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
 Oct 1, 1998 Resolved

What the violations mean

Total Trihalomethanes (TTHMs)

1 incident

Disinfection byproduct levels exceeded the federal limit

Long-term TTHM exposure may increase bladder cancer risk

Where the water comes from

City of Seguin draws water from 2 surface water intakes. It also buys water from Schertz Seguin Local Government Corporat.

Buys water from

Annual water quality report

City of Seguin must give its customers an annual water quality report (Consumer Confidence Report) by July 1, with the levels its tests found in the previous year.

Systems serving 10,000 or more people must mail or deliver the report to every customer, and from 2027 they must send it twice a year.

Find a posted report with EPA's Consumer Confidence Report search

Testing your own water

To test the water at your tap, or a private well this record does not cover, use a laboratory certified for drinking water by Texas.

Certified drinking water labs by state EPA guidance for private wells