Community Water System · PWS 055295401
Lac Du Flambeau
Operator location Lac Du Flambeau, EPA Region 5 — Tribal Water Systems - UCMR5 detected 1 PFAS compound (lower-third PFAS panel (≤ 2 compounds)) on this PWS; SDWIS lists 17 violations and 3,168 people served.
- 3,168
- People served (this PWS)
- 17
- EPA violations (this PWS)
- 2
- Health-based (this PWS)
- 1 PFAS
- UCMR5 (this PWS)
Lac Du Flambeau standing, low SDWIS violation third
UCMR5 detected 1 PFAS compound - lower-third PFAS panel (≤ 2 compounds). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 12% is middle-third health share (≤ 23%). UCMR5: lower-third PFAS panel (≤ 2 compounds). Population rank #10,236 of 29,740 among systems serving 500+.
The verdict
Lac Du Flambeau is in the lower third by violation count (17; lower-third violation load (≤ 21 violations)). A low count does not mean the system is unmonitored - monitoring and reporting violations still appear in SDWIS. Population served is mid-pack at 3,168 (mid served population (≤ 3,309)). Health-based share is 12% (middle-third health share (≤ 23%)). UCMR5 detected 1 PFAS compound (lower-third PFAS panel (≤ 2 compounds)).
- #10,236 of 29,740
- Population · /systems
- #12 of 46
- Population · 05
- 17
- Total EPA violations on record
- 12%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
1 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.
System Details
- System Type
- Community
- Owner Type
- Native American
- Connections
- 641
- School/Daycare
- No
- MCL Violations
- 2
- Monitoring Violations
- 12
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Thallium, Total | MR | 4 | 2017 |
| Coliform (TCR) | MR | 3 | 1999 |
| Revised Total Coliform Rule | RPT | 3 | 2023 |
| Coliform (TCR) | MCL | 2 | 2012 |
| Fluoride | MR | 2 | 2011 |
| Gross Alpha, Excl. Radon and U | MR | 1 | 2008 |
| Combined Radium (-226 and -228) | MR | 1 | 2008 |
| Combined Uranium | MR | 1 | 2008 |
Violation Count vs. the National Corpus
Lac Du Flambeau has 17 recorded EPA violations, 28% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 71% carry more. 12% of this system's own violations are health-based (2 of 17), and it ranks #10,236 of 29,740 by population served among that same cohort.
EPA violations vs. the national water-system corpus
Public water systems serving 500+ people (EPA SDWIS)
17 Lower than most fewer violations than 71% of 29,740 water systems
the national water-system corpus, bucketed by value
Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source EPA SDWIS · 2026-05-15
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 1 of 58 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| PFTrDA | 6/11/2025 | <7.00 ppt | 7.00 ppt | Not Detected |
| PFMPA | 6/11/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFBS | 6/11/2025 | 8.20 ppt | 3.00 ppt | Detected |
| PFHpS | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 6/11/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| NFDHA | 6/11/2025 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFEESA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 8:2 FTS | 6/11/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFMBA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| NEtFOSAA | 6/11/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTA | 6/11/2025 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFHpA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 4:2 FTS | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| NMeFOSAA | 6/11/2025 | <6.00 ppt | 6.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 6/11/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBA | 6/11/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFPeA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| HFPO-DA | 6/11/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 9Cl-PF3ONS | 6/11/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| 6:2 FTS | 6/11/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFUnA | 6/11/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFHxA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOA | 6/11/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOS | 6/11/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFNA | 6/11/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHxS | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| ADONA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 9Cl-PF3ONS | 6/11/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 6/11/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFUnA | 6/11/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFHxA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOA | 6/11/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOS | 6/11/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFNA | 6/11/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHxS | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| ADONA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| NMeFOSAA | 6/11/2025 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFEESA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBS | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpS | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTA | 6/11/2025 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFTrDA | 6/11/2025 | <7.00 ppt | 7.00 ppt | Not Detected |
| NEtFOSAA | 6/11/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFPeA | 6/11/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| NFDHA | 6/11/2025 | <20.00 ppt | 20.00 ppt | Not Detected |
UCMR5 PFAS record for Lac Du Flambeau
Open EPA SDWIS federal reports for PWS 055295401 to cross-check UCMR5 detections and violation codes; state primacy agencies enforce the Safe Drinking Water Act locally.
Sources: EPA SDWIS
Nationwide peers
17 violations · 3,168 served: nearest cross-state SDWIS matches.
Cross-state systems with similarly light violation ledgers
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
Cross-state systems near this population served
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Lac Du Flambeau
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in EPA Region 5 — Tribal Water Systems compares on the same EPA violation measures. EPA Region 5 — Tribal Water Systems systems
- Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
- Find and compare another public water system by name or PWSID. Search systems
EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.