Great Falls City of

PWSID: MT0000525

No active violations
This system has no unresolved violations. The most recent violation on record was 2019-04-01.

Violation trend: 0.0 per year over the last 5 years, down from 1.0 per year in the previous 5.

System Details

Population Served60,000
Service Connections22,477
Water SourceSurface Water
System TypeCommunity Water System
OwnerLocal Government
StatusActive
CityGreat Falls
EPA ZIP on File59403

Areas Served

  • Great Falls, Cascade County

Lead & Copper Testing

ContaminantLevelEPA Action LevelStatus
Lead (90th percentile)0.0100 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0090 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0090 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0080 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0080 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0070 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0050 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0040 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0030 mg/L0.015 mg/LBelow Action Level

Violation History (5 total)

ContaminantViolationDateHealth-BasedStatus
2456MCL
Measured: 61.00 UG/L (limit: 60.00 UG/L)
2019-04-01YesReturned to Compliance
2456MCL
Measured: 72.50 UG/L (limit: 60.00 UG/L)
2019-01-01YesReturned to Compliance
2456MCL
Measured: 74.80 UG/L (limit: 60.00 UG/L)
2018-10-01YesReturned to Compliance
2456MCL
Measured: 73.80 UG/L (limit: 60.00 UG/L)
2018-07-01YesReturned to Compliance
2456MCL
Measured: 60.50 UG/L (limit: 60.00 UG/L)
2018-04-01YesReturned to Compliance

Understanding This Water System's Record

Great Falls City of is a community water system water system that draws from surface water sources and serves a population of 60,000 in Great Falls, 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.