Here is what the EPA's own data shows about tap water in Monroe. According to EPA SDWIS data retrieved October 2026, Monroe is served by 3 active community water systems, together reported to serve about 104,892 people.
As of October 2026, EPA records show 54 violations across the community water system(s) serving Monroe, going back to the earliest EPA record. 3 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 Revised Total Coliform Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded once in June 2017. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
Monroe South County
33,816 served · surface water · PWSID MI0004455
Health-based TTHM: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times between July 2015 and October 2015. The EPA record lists a level of 0.093 MG/L; the limit (MCL) is 0.08 MG/L. All have since returned to compliance, per EPA records.
Monitoring Chloride: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in July 2023. All have since returned to compliance, per EPA records.
Frenchtown Township
21,609 served · surface water · PWSID MI0002500
Monitoring 1,2,4-Trichlorobenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring cis-1,2-Dichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring Xylenes, Total: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring DICHLOROMETHANE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring o-Dichlorobenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring p-Dichlorobenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring Vinyl chloride: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring 1,1-Dichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring trans-1,2-Dichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring 1,2-Dichloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring 1,1,1-Trichloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring Carbon tetrachloride: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring 1,2-Dichloropropane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring Trichloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring 1,1,2-Trichloroethane: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring Tetrachloroethylene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring CHLOROBENZENE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring Benzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring Toluene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring Ethylbenzene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring Styrene: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between April 2022 and April 2024. All have since returned to compliance, per EPA records.
Monitoring TTHM: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between June 2019 and April 2024. All have since returned to compliance, per EPA records.
Monitoring Total Haloacetic Acids (HAA5): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times between June 2019 and April 2024. All have since returned to compliance, per EPA records.
Monitoring CARBON, TOTAL: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2024. All have since returned to compliance, per EPA records.
Monitoring Bromate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2024. All have since returned to compliance, per EPA records.
Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in July 2023. All have since returned to compliance, per EPA records.
Monitoring Revised Total Coliform Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in September 2022. 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.