MT / Sweet Grass
MT · Tap water records
Sweet Grass tap water, in plain English
Here is what the EPA's own data shows about tap water in Sweet Grass. According to EPA SDWIS data retrieved June 2026, Sweet Grass is served by 2 active community water systems, together reported to serve about 200 people.
As of June 2026, EPA records show 46 violations across the community water system(s) serving Sweet Grass, 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.
What the EPA has on record, by system
Sweetgrass Water Users Assn
100 served · surface water · PWSID MT0000340 - Health-based TTHM: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 3 times in July 2025. The EPA record lists a level of 0.083 MG/L; the limit (MCL) is 0.08 MG/L. 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 10 times between July 2000 and October 2024. EPA records do not show all of these as returned to compliance.
- Monitoring TTHM: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 11 times between January 2020 and January 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 11 times between January 2020 and January 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 5 times in January 2024. EPA records do not show all of these as returned to compliance.
- 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 January 2017. All have since returned to compliance, per EPA records.
- Monitoring Coliform (TCR): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in December 2015. 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 2 times between July 2000 and July 2008. All have since returned to compliance, per EPA records.
Hillside Colony Inc
100 served · groundwater · PWSID MT0001782 - 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 2015. All have since returned to compliance, per EPA records.
- Monitoring Gross Alpha, Excl. Radon and U: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in January 2008. EPA records do not show all of these as returned to compliance.
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 June 2026. Records cover the EPA's full reporting history for these systems. Verify at EPA ECHO.