Community Water System · PWS WI7350127
Tomahawk Waterworks
Operator location Tomahawk, Wisconsin - 38% of 29 violations are health-based (upper-third health share (> 23%)); groundwater source; 3,180 served per SDWIS.
- 3,180
- People served (this PWS)
- 29
- EPA violations (this PWS)
- 11
- Health-based (this PWS)
- 5 PFAS
- UCMR5 (this PWS)
Tomahawk Waterworks standing, mid SDWIS violation third
38% of 29 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 38% is upper-third health share (> 23%). UCMR5: upper-third PFAS panel (> 4 compounds). Population rank #10,212 of 29,740 among systems serving 500+.
The verdict
Tomahawk Waterworks lands in the middle third by violation volume (29), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is mid-pack at 3,180 (mid served population (≤ 3,309)). Health-based share is 38% - most of this ledger is MCL or treatment-technique exceedance. UCMR5 detected 5 PFAS compounds (upper-third PFAS panel (> 4 compounds)).
- #10,212 of 29,740
- Population · /systems
- #199 of 744
- Population · WI
- 29
- Total EPA violations on record
- 38%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
5 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 1,500
- County
- Lincoln
- School/Daycare
- No
- MCL Violations
- 10
- Monitoring Violations
- 0
- Treatment Tech Violations
- 1
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Consumer Confidence Rule | Other | 13 | 2012 |
| Coliform (TCR) | MCL | 10 | 2002 |
| LEAD AND COPPER RULE REVISIONS | TT | 1 | 2024 |
| Public Notice | Other | 1 | 2024 |
Violation Count vs. the National Corpus
Tomahawk Waterworks has 29 recorded EPA violations, 41% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 58% carry more. 38% of this system's own violations are health-based (11 of 29), and it ranks #10,212 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)
29 Lower than most fewer violations than 58% 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. 20 of 116 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| PFNA | 4/24/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFBA | 4/24/2024 | 7.80 ppt | 5.00 ppt | Detected |
| HFPO-DA | 4/24/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| ADONA | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| 9Cl-PF3ONS | 4/24/2024 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 4/24/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHxA | 4/24/2024 | 7.50 ppt | 3.00 ppt | Detected |
| PFBS | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOS | 4/24/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHxS | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 4/24/2024 | 6.50 ppt | 3.00 ppt | Detected |
| 6:2 FTS | 4/24/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFDA | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| 4:2 FTS | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| 8:2 FTS | 4/24/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFMPA | 4/24/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFPeA | 4/24/2024 | 7.90 ppt | 3.00 ppt | Detected |
| PFMBA | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFEESA | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| NFDHA | 4/24/2024 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFHpS | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTA | 4/24/2024 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFTrDA | 4/24/2024 | <7.00 ppt | 7.00 ppt | Not Detected |
| NEtFOSAA | 4/24/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| NMeFOSAA | 4/24/2024 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFOA | 4/24/2024 | 20.00 ppt | 4.00 ppt | Detected |
| PFUnA | 4/24/2024 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFPeS | 4/24/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFDoA | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTrDA | 4/24/2024 | <7.00 ppt | 7.00 ppt | Not Detected |
| PFUnA | 4/24/2024 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFHxA | 4/24/2024 | 6.30 ppt | 3.00 ppt | Detected |
| PFDA | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOA | 4/24/2024 | 19.00 ppt | 4.00 ppt | Detected |
| PFOS | 4/24/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 4/24/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| NEtFOSAA | 4/24/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFNA | 4/24/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFTA | 4/24/2024 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFDoA | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBS | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeA | 4/24/2024 | 6.40 ppt | 3.00 ppt | Detected |
| PFHxS | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMPA | 4/24/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| 4:2 FTS | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpS | 4/24/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 4/24/2024 | 5.20 ppt | 3.00 ppt | Detected |
| 9Cl-PF3ONS | 4/24/2024 | <2.00 ppt | 2.00 ppt | Not Detected |
| NMeFOSAA | 4/24/2024 | <6.00 ppt | 6.00 ppt | Not Detected |
| NFDHA | 4/24/2024 | <20.00 ppt | 20.00 ppt | Not Detected |
Health-based violations on Tomahawk Waterworks
11 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for WI7350127.
Sources: EPA SDWIS · Wisconsin DNR, Drinking Water and Groundwater
Nationwide peers
29 violations · 3,180 served: nearest cross-state SDWIS matches.
Cross-state systems near this violation count
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 Tomahawk Waterworks
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Wisconsin compares on the same EPA violation measures. Wisconsin 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.