State Hub
Montana Water Quality
145
Utilities in database
0.7M
Residents served
0
With open violations
36
PFAS monitored
Quick Answer
Montana public drinking water is served by 145 EPA-tracked water systems, providing service to approximately 0.7 million residents through public utilities. No open health-based violations are currently recorded across tracked systems in the EPA federal database. 36 systems have official PFAS monitoring records from the EPA UCMR 5 program (2023–2025). About 48% of MT residents use private wells, which fall outside federal utility compliance monitoring.
No open health-based violations are currently recorded in the EPA SDWIS database for Montana's tracked water systems. Always verify with your utility's Consumer Confidence Report for annual test results.
Drinking Water in Montana
Montana has 145 community water systems serving approximately 0.7 million residents. Primary water sources include groundwater. The most commonly reported contaminants include disinfection byproducts, nitrates. 48% of Montana residents rely on private wells. MDEQ holds primary enforcement authority under the Safe Drinking Water Act.
Safest Large Utilities
Montana systems with no open health violations serving 10,000+ residents.
Utilities in Montana
51–75 of 145City of Townsend
MT0000344 · 2,000 served
Eastgate Village Sewer and Water
MT0001784 · 2,000 served
Town of Eureka
MT0000210 · 1,995 served
Fairmont Hot Springs Resort
MT0000589 · 1,965 served
City of Thompson Falls
MT0000341 · 1,950 served
Roundup Water Department
MT0000321 · 1,900 served
City of Three Forks
MT0000343 · 1,900 served
Town of Columbus
MT0000185 · 1,900 served
City of Baker
MT0000021 · 1,858 served
City of Malta
MT0000284 · 1,800 served
Town of Manhattan
MT0000285 · 1,800 served
Sun Prairie Village County
MT0000521 · 1,800 served
Hill County Water Districts
MT0000249 · 1,720 served
Town of Plains
MT0000305 · 1,700 served
Plentywood Water Department
MT0000306 · 1,700 served
City of Choteau
MT0000175 · 1,691 served
City of Big Timber
MT0000463 · 1,650 served
Seeley Lake Water District
MT0000327 · 1,575 served
Virginia City Water Dept
MT0000353 · 1,500 served
Town of Whitehall
MT0000359 · 1,500 served
City of Fort Benton
MT0000216 · 1,500 served
Town of Ennis
MT0000208 · 1,400 served
City of Boulder
MT0000158 · 1,400 served
Town of Philipsburg
MT0000304 · 1,360 served
El Mar Estates Msla Co Water
MT0000517 · 1,350 served
Key Contaminant Concerns in Montana
These contaminants appear most frequently in Montana utility records or pose elevated risk in this region based on EPA data.
Nitrates
Nitrate (NO₃⁻) is a nitrogen-containing compound that forms naturally through the decomposition of organic matter. At elevated concentrations — almost always caused by human activity — nitrate is converted in the digestive system to nitrite, which then reacts with hemoglobin to form methemoglobin, a form of hemoglobin that cannot carry oxygen. In the body, nitrite also reacts with amines in food to form N-nitroso compounds (nitrosamines) — known carcinogens classified by the IARC as Group 2A (probable human carcinogens). The United States applies over 23 million tons of nitrogen fertilizer annually, making agricultural runoff the dominant source of nitrate contamination in U.S. groundwater.
EPA limit: 10 mg/L
DBPs
When utilities add chlorine to water to kill pathogens, it reacts with dissolved organic matter — leaves, algae, soil — to produce disinfection byproducts (DBPs). Over 600 DBPs have been identified. The EPA regulates two groups: total trihalomethanes (TTHMs, including chloroform) and haloacetic acids (HAA5). DBP levels tend to be highest in surface water systems and in warm months when organic matter is elevated.
EPA limit: 80 µg/L (TTHMs) / 60 µg/L (HAA5)
City Water Reports in Montana
Tap water quality pages for Montana cities — violations, PFAS records, utility profiles, and official source links.
Independent Water Testing
Find a certified lab in Montana
Utility compliance records show what water systems report to the EPA. An independent test from a certified laboratory confirms what's actually in your tap water. Montana labs can test for PFAS, lead, nitrates, bacteria, and dozens of other contaminants.
Explore Water Quality in Montana
City of Townsend
Violation history, PFAS records, and official source links
Eastgate Village Sewer and Water
Violation history, PFAS records, and official source links
Town of Eureka
Violation history, PFAS records, and official source links
PFAS monitoring records — Montana
36 water systems in Montana with EPA UCMR 5 records
Lead in Montana drinking water
State-specific lead data, violation utilities, and testing guidance
PFAS in Montana drinking water
State-specific PFAS data, MCL context, and treatment options
Certified water testing labs in Montana
Labs certified for PFAS (EPA 533/537.1), lead, and bacteria testing
Water treatment options
Reverse osmosis, activated carbon, and filtration guides with cost ranges
Data sources and methodology
How WaterUtilityReport.com sources and validates official EPA data
Common Questions About Montana Drinking Water
Does Montana drinking water have PFAS?
36 Montana water systems have EPA UCMR 5 PFAS monitoring records (2023–2025)
Which Montana water utilities have open violations?
Browse Montana utility compliance records and violation history
How do I test my water in Montana?
State-certified labs for PFAS (EPA 533/537.1), lead, nitrate, and bacteria testing
What treatment removes PFAS from MT tap water?
Reverse osmosis removes PFAS, lead, arsenic, and nitrates — cost, maintenance, and NSF certification explained
What do Montana PFAS records tell me about my water?
EPA limits, health context, and what UCMR 5 detection above MRL means for your water
How is Montana water quality data sourced here?
EPA SDWIS violations, UCMR 5 PFAS records, and CCR data — sources, accuracy notes, and limitations
Montana Water FAQs
Data sources: Utility compliance and violation data from EPA SDWIS (Safe Drinking Water Information System). PFAS monitoring records from EPA UCMR 5 (Unregulated Contaminant Monitoring Rule 5, 2023–2025). Contaminant data from EPA and ATSDR public references. This page summarizes public records — it is not a compliance determination. Methodology →
Last updated: 2026-04-23