Here is what the EPA's own data shows about tap water in Marlin. According to EPA SDWIS data retrieved October 2026, Marlin is served by 2 active community water systems, together reported to serve about 11,320 people.
As of October 2026, EPA records show 207 violations across the community water system(s) serving Marlin, going back to the earliest EPA record. 164 of these are classified by the EPA as health-based (a contaminant recorded above the limit the EPA tracks); the rest are monitoring or reporting violations. Each is listed by system below, with its status.
Health-based Total Haloacetic Acids (HAA5): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 19 times between July 2015 and April 2026. The EPA record lists a level of 0.062 MG/L; the limit (MCL) is 0.06 MG/L. EPA records do not show all of these as returned to compliance.
Health-based TTHM: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 5 times between April 2024 and January 2026. The EPA record lists a level of 0.084 MG/L; the limit (MCL) is 0.08 MG/L. All have since returned to compliance, per EPA records.
Health-based Long Term 2 Enhanced Surface Water Treatment Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 10 times between July 2015 and April 2021. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
Health-based Revised Total Coliform Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times between October 2018 and June 2020. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
Health-based Interim Enhanced Surface Water Treatment Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 7 times between November 2015 and July 2017. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
Monitoring Public Notice: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 22 times between October 2011 and August 2025. EPA records do not show all of these as returned to compliance.
Monitoring LEAD AND COPPER RULE REVISIONS: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in July 2025. EPA records do not show all of these as returned to compliance.
Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times between July 2022 and July 2025. EPA records do not show all of these as returned to compliance.
Monitoring Total Haloacetic Acids (HAA5): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in June 2024. All have since returned to compliance, per EPA records.
Monitoring Surface Water Treatment Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times between November 2015 and February 2023. All have since returned to compliance, per EPA records.
Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times between December 2014 and December 2021. All have since returned to compliance, per EPA records.
Monitoring Long Term 2 Enhanced Surface Water Treatment Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in December 2019. All have since returned to compliance, per EPA records.
Monitoring Interim Enhanced Surface Water Treatment Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 7 times between July 2015 and June 2016. All have since returned to compliance, per EPA records.
Tri County Sud
5,353 served · groundwater · PWSID TX0730004
Health-based Arsenic: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 121 times between January 2016 and January 2026. The EPA record lists a level of 0.023 MG/L; the limit (MCL) is 0.01 MG/L. EPA records do not show all of these as returned to compliance.
Monitoring Public Notice: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2019. EPA records do not show all of these as returned to compliance.
Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in December 2016. All have since returned to compliance, per EPA records.
What this means
A health-based violation means a contaminant was recorded above the limit the EPA tracks for it. A monitoring or reporting violation means a required test or report was late or missed — not that a contaminant was measured above a limit. “Returned to compliance” means the EPA recorded the issue as resolved.
This page summarizes the EPA's own records and does not assess whether your water is safe to drink. For the most current details, you can verify every record directly with the EPA, and contact your water system with questions.
Source: U.S. EPA Envirofacts SDWIS, retrieved October 2026. Records cover the EPA's full reporting history for these systems. Verify at EPA ECHO.