Lewistown City of

PWSID: MT0000271

No active violations
This system has no unresolved violations. The most recent violation on record was 2025-07-01.

This system has more violations on record than 93% of water systems in Montana.

Violation trend: 0.2 per year over the last 5 years, down from 0.6 per year in the previous 5.

System Details

Population Served5,923
Service Connections2,906
Water SourceGroundwater
System TypeCommunity Water System
OwnerLocal Government
StatusActive
CityLewistown
EPA ZIP on File59457

Areas Served

  • Lewistown, Fergus County

Lead & Copper Testing

ContaminantLevelEPA Action LevelStatus
Lead (90th percentile)0.0050 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0000 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0000 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0000 mg/L0.015 mg/LBelow Action Level

Violation History (64 total)

ContaminantViolationDateHealth-BasedStatus
7000Other2025-07-01Returned to Compliance
3014MR2017-11-15 MajorReturned to Compliance
7000Other2017-07-01Returned to Compliance
3014MR2016-11-23 MajorReturned to Compliance
3100MCL2016-03-01YesReturned to Compliance
3100MCL2015-12-01YesReturned to Compliance
7000Other2015-07-01Returned to Compliance
1005MR2014-01-01 MajorReturned to Compliance
1010MR2014-01-01 MajorReturned to Compliance
1015MR2014-01-01 MajorReturned to Compliance
1020MR2014-01-01 MajorReturned to Compliance
1025MR2014-01-01 MajorReturned to Compliance
1035MR2014-01-01 MajorReturned to Compliance
1036MR2014-01-01 MajorReturned to Compliance
1074MR2014-01-01 MajorReturned to Compliance
1075MR2014-01-01 MajorReturned to Compliance
1085MR2014-01-01 MajorReturned to Compliance
1045MR2014-01-01 MajorReturned to Compliance
2005MR2014-01-01 MajorReturned to Compliance
2010MR2014-01-01 MajorReturned to Compliance
2015MR2014-01-01 MajorReturned to Compliance
2020MR2014-01-01 MajorReturned to Compliance
2031MR2014-01-01 MajorReturned to Compliance
2035MR2014-01-01 MajorReturned to Compliance
2036MR2014-01-01 MajorReturned to Compliance
2037MR2014-01-01 MajorReturned to Compliance
2039MR2014-01-01 MajorReturned to Compliance
2040MR2014-01-01 MajorReturned to Compliance
2041MR2014-01-01 MajorReturned to Compliance
2042MR2014-01-01 MajorReturned to Compliance
2046MR2014-01-01 MajorReturned to Compliance
2050MR2014-01-01 MajorReturned to Compliance
2051MR2014-01-01 MajorReturned to Compliance
2065MR2014-01-01 MajorReturned to Compliance
2067MR2014-01-01 MajorReturned to Compliance
2105MR2014-01-01 MajorReturned to Compliance
2110MR2014-01-01 MajorReturned to Compliance
2274MR2014-01-01 MajorReturned to Compliance
2306MR2014-01-01 MajorReturned to Compliance
2326MR2014-01-01 MajorReturned to Compliance
2959MR2014-01-01 MajorReturned to Compliance
2378MR2014-01-01 MajorReturned to Compliance
2380MR2014-01-01 MajorReturned to Compliance
2955MR2014-01-01 MajorReturned to Compliance
2964MR2014-01-01 MajorReturned to Compliance
2968MR2014-01-01 MajorReturned to Compliance
2969MR2014-01-01 MajorReturned to Compliance
2976MR2014-01-01 MajorReturned to Compliance
2977MR2014-01-01 MajorReturned to Compliance
2979MR2014-01-01 MajorReturned to Compliance

Showing 50 of 64 historical violations.

Understanding This Water System's Record

Lewistown City of is a community water system water system that draws from groundwater sources and serves a population of 5,923 in Lewistown, Montana. This page shows its complete compliance history as reported to the EPA's Safe Drinking Water Information System (SDWIS), the federal database that tracks every public water system in the United States.

What Do These Violations Mean?

Health-based violations mean the system exceeded an EPA maximum contaminant level (MCL) or failed to provide required treatment. These indicate potential health risks from contaminants like lead, arsenic, bacteria, nitrates, or disinfection byproducts. Non-health-based violations involve monitoring, reporting, or procedural requirements — the system missed a testing deadline or failed to notify customers, but contaminant levels were not necessarily unsafe.

What Should You Do?

Your water utility is required to publish an annual Consumer Confidence Report (CCR) that details test results and any violations. If your system has active health-based violations, consider a certified water filter rated for the specific contaminants involved. The contaminant guides on this site explain health risks and filter options for common pollutants. For the most current results, contact your water utility directly — EPA data can lag weeks or months behind real-time testing.