Community Water System · PWS MT0000318
Ronan City Of
Ronan, Montana 59864 - drinking water served from surface water sources to 2,483 people, tracked in EPA SDWIS and UCMR5.
- 2,483
- People served
- 259
- EPA violations
- 9
- Health-based
- Untested
- UCMR5 result
The verdict
EPA records 259 drinking-water violations at Ronan City Of, 3% of them health-based - above the Montana per-system average.
- 259
- Total EPA violations on record
- 3%
- Health-based (MCL / treatment failure)
- 2,483
- People served by this system
- N/A
- PFAS compounds detected (UCMR5)
Water Quality Snapshot: Ronan City Of
Ronan City Of is a local-owned community water system that delivers drinking water to 2,483 residents in Ronan, Montana (Lake County) through 1,004 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 259 total violations for this system , of which 9 (3%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 247 monitoring and reporting violations are on file. The most recent violation on record dates to 2025.
The most frequently cited contaminant at this system is Surface Water Treatment Rule, recorded in 9 violations (TT, health-based). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.
Across Montana, EPA tracks 2,263 public water systems serving 1,112,267 people, with 297,270 cumulative violations and 25,922 health-based violations on record. About 95% of systems in the state carry at least one violation, and state-wide the average per system is 131.4 violations. Statewide, 28 of 45 UCMR5-tested systems have reported PFAS detections (62.2%).
Ronan City Of's 259 violations sit above the Montana average.
All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 1,004
- County
- Lake
- School/Daycare
- No
- MCL Violations
- 0
- Monitoring Violations
- 247
- Treatment Tech Violations
- 9
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Surface Water Treatment Rule | TT | 9 | 2011 |
| Combined Radium (-226 and -228) | MR | 8 | 2014 |
| Gross Alpha, Excl. Radon and U | MR | 8 | 2014 |
| 1,2,4-Trichlorobenzene | MR | 6 | 2023 |
| Xylenes, Total | MR | 6 | 2023 |
| o-Dichlorobenzene | MR | 6 | 2023 |
| p-Dichlorobenzene | MR | 6 | 2023 |
| Vinyl chloride | MR | 6 | 2023 |
| 1,1-Dichloroethylene | MR | 6 | 2023 |
| trans-1,2-Dichloroethylene | MR | 6 | 2023 |
| 1,2-Dichloroethane | MR | 6 | 2023 |
| 1,1,1-Trichloroethane | MR | 6 | 2023 |
| 1,2-Dichloropropane | MR | 6 | 2023 |
| Trichloroethylene | MR | 6 | 2023 |
| 1,1,2-Trichloroethane | MR | 6 | 2023 |
| Tetrachloroethylene | MR | 6 | 2023 |
| CHLOROBENZENE | MR | 6 | 2023 |
| Toluene | MR | 6 | 2023 |
| Ethylbenzene | MR | 6 | 2023 |
| Styrene | MR | 6 | 2023 |
| DICHLOROMETHANE | MR | 6 | 2023 |
| Carbon tetrachloride | MR | 6 | 2023 |
| Benzene | MR | 6 | 2023 |
| Arsenic | MR | 6 | 2005 |
| Surface Water Treatment Rule | MR | 6 | 2025 |
| cis-1,2-Dichloroethylene | MR | 6 | 2023 |
| Coliform (TCR) | MR | 4 | 2012 |
| BHC-GAMMA | MR | 3 | 2014 |
| Dalapon | MR | 3 | 2014 |
| Di(2-ethylhexyl) adipate | MR | 3 | 2014 |
Verify This Water System
The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Ronan City Of.
EPA SDWIS, Federal Reports
EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:
View PWS ID MT0000318 on SDWISSource: EPA SDWIS Federal Reports Search
Montana Drinking Water Authority
Montana's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.
Find MT regulator via EPA SDWISViolation Timeline
Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.
| Year (latest) | Contaminant | Category | Count | EPA Record |
|---|---|---|---|---|
| 2025 | Surface Water Treatment Rule | MR | 6 | SDWIS / MT0000318 / 0200 |
| 2023 | 1,2,4-Trichlorobenzene | MR | 6 | SDWIS / MT0000318 / 2378 |
| 2023 | Xylenes, Total | MR | 6 | SDWIS / MT0000318 / 2955 |
| 2023 | o-Dichlorobenzene | MR | 6 | SDWIS / MT0000318 / 2968 |
| 2023 | p-Dichlorobenzene | MR | 6 | SDWIS / MT0000318 / 2969 |
| 2023 | Vinyl chloride | MR | 6 | SDWIS / MT0000318 / 2976 |
| 2023 | 1,1-Dichloroethylene | MR | 6 | SDWIS / MT0000318 / 2977 |
| 2023 | trans-1,2-Dichloroethylene | MR | 6 | SDWIS / MT0000318 / 2979 |
| 2023 | 1,2-Dichloroethane | MR | 6 | SDWIS / MT0000318 / 2980 |
| 2023 | 1,1,1-Trichloroethane | MR | 6 | SDWIS / MT0000318 / 2981 |
| 2023 | 1,2-Dichloropropane | MR | 6 | SDWIS / MT0000318 / 2983 |
| 2023 | Trichloroethylene | MR | 6 | SDWIS / MT0000318 / 2984 |
| 2023 | 1,1,2-Trichloroethane | MR | 6 | SDWIS / MT0000318 / 2985 |
| 2023 | Tetrachloroethylene | MR | 6 | SDWIS / MT0000318 / 2987 |
| 2023 | CHLOROBENZENE | MR | 6 | SDWIS / MT0000318 / 2989 |
How Ronan City Of Compares
Cross-reference this system's record against state averages and the federal MCL framework for context.
| Metric | Ronan City Of | Montana avg | Federal benchmark |
|---|---|---|---|
| Total violations | 259 | 131.4 | SDWA compliance, any non-zero count is a recorded breach |
| Health-based violations | 9 | 11.5 | Indicates a contaminant exceeded a federal MCL |
| PFAS detection | None | 62.2% | EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt |
| Population served | 2,483 | 492 | Sizing context for compliance burden |
Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 2,263 regulated public water systems in Montana.
Federal MCL reference, Safe Drinking Water Act thresholds ▼
| Contaminant | Federal MCL / Action Level | Note |
|---|---|---|
| Lead | 0 mg/L (Action Level: 0.015 mg/L) | Lead and Copper Rule treatment technique |
| Arsenic | 0.010 mg/L (10 ppb) | Health-based MCL since 2006 |
| Total Coliform | Treatment technique (RTCR) | Indicator organism, monitoring trigger |
| PFOA / PFOS (PFAS) | 4.0 ppt each (final 2024 rule) | Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026) |
| Nitrate (as N) | 10 mg/L | Acute health risk for infants |
Frequently Asked Questions
Is Ronan City Of water safe to drink? ▼
How many people does Ronan City Of serve? ▼
What type of violations does Ronan City Of have? ▼
Has PFAS been detected in Ronan City Of water? ▼
What water source does Ronan City Of use? ▼
Where does this data come from? ▼
Read our methodology - how this data is sourced, computed, and verified.
Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.