Tomah Waterworks water quality report, rewritten
- Serves
- 9,192
- Connections
- 3,139
- Water source
- Groundwater
- Based in
- Tomah, WI
- County
- Monroe
- Owner
- Local government
The ZIP code it serves
PWSID WI6420254 · EPA data
Read this first
Nothing in the federal data for this utility is above a health goal. That covers PFAS, lithium, lead and copper; it does not cover everything, so read what this report cannot tell you below.
11 health-based violations since 2016. Details are below.
What was found
Highlighted: above the health goal, or EPA’s health benchmark where there is no goal. Circled: above the legal limit in at least one sample, or the action level. Every scale puts that line at its middle.
PFAS and lithium: EPA UCMR 5, samples taken from March 20, 2023 to Sept. 25, 2023. Each blue tick on a scale is one sample where it was found.
NSF’s PFAS claims are tested to below 20 ppt. EPA’s limit is 10 ppt, and EPA says no certification yet shows a filter reaching its levels.
PFHxS
Comes from the source
5.7ppt
Highest of 10 samples; found in three
Detected, below the legal limit and the health goal.
What handles it
- NSF/ANSI 53Look for: Total PFAS Reduction
Also found, with no federal limit
EPA measured these PFAS to learn how often they occur. None has a legal limit or a health goal yet.
| Compound | Highest sample | Found in | Certification claim |
|---|---|---|---|
| PFPeA | 5.1 ppt | 2 of 10 | None covers it |
| PFHxA | 3.9 ppt | 2 of 10 | None covers it |
Tested and not found
Below EPA’s minimum reporting level in every sample taken from March 20, 2023 to Sept. 25, 2023. Not found means not measured above that level, which is not the same as zero.
All 28 compounds tested and not found
- 11Cl-PF3OUdS
- 4:2 FTS
- 6:2 FTS
- 8:2 FTS
- 9Cl-PF3ONS
- ADONA
- HFPO-DA (GenX)
- Lead
- Lithium
- NEtFOSAA
- NFDHA
- NMeFOSAA
- PFBA
- PFBS
- PFDA
- PFDoA
- PFEESA
- PFHpA
- PFHpS
- PFMBA
- PFMPA
- PFNA
- PFOA
- PFOS
- PFPeS
- PFTA
- PFTrDA
- PFUnA
Violations since 2016
| Contaminant or rule | Type | Period | Measured | Status |
|---|---|---|---|---|
| Nitrate | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2025 to June 30, 2025 | 11.1 MG/L | Archived |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2018 to June 30, 2018 | 7.0 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2018 to March 31, 2018 | 7.3 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2017 to Dec. 31, 2017 | 6.8 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2017 to Sept. 30, 2017 | 6.3 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2017 to June 30, 2017 | 6.3 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2017 to March 31, 2017 | 6.1 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2016 to Dec. 31, 2016 | 6.5 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2016 to Sept. 30, 2016 | 6.5 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2016 to June 30, 2016 | 6.5 PCI/L | Resolved |
| Combined Radium (-226 and -228) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2016 to March 31, 2016 | 6.5 PCI/L | Resolved |
| Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 3 monitoring or reporting violations not shown. | ||||
What this report cannot tell you
- Levels of everything else. Federal bulk data carries results for PFAS, lithium, lead and copper, and violations for the rest. Nitrate, arsenic, disinfection byproducts and other levels are in Tomah Waterworks’s own annual report, which it must send you every year.
- Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.
- Anything after the latest data. SDWIS data is from 2026 Q2; UCMR 5 samples are from March 20, 2023 to Sept. 25, 2023.
Other Wisconsin utilities
- Milwaukee Waterworks626,000
- Madison Water Utility272,000
- Green Bay Waterworks107,369
- Racine Waterworks105,100
- Kenosha Water Utility99,218
- Appleton Waterworks74,511
- Waukesha Water Utility70,718
- Eau Claire Waterworks70,587
- Janesville Water Utility64,415
- West Allis Waterworks63,240
- Oshkosh Waterworks63,000
- La Crosse Waterworks53,000
Sources
- EPA UCMR 5 occurrence data, file of Aug. 27, 2026
- EPA SDWA bulk download (SDWIS federal data), 2026 Q2
- Limits and goals: each contaminant’s page, with its EPA source.
- How this page is built: methodology.
What to do next
Nothing here is above a health goal
In the federal data for this utility. That data does not cover everything, which is why the next step matters.
Every contaminant TapBuff tracksGet the utility’s own report
Tomah Waterworks must send you a water quality report every year. It lists nitrate, arsenic and byproduct levels this page cannot.
How to read itTest your own tap for lead
Your service line, solder and fixtures decide the lead at your faucet, not the utility’s average.
Lead in your water: what to doDecide if you want a filter at all
A filter for taste or chlorine is a preference, not a need. The standards say what each kind can do.
NSF/ANSI standards, decoded