Marshfield Utilities water quality
Marshfield, WI · serves 18,815 people (7,999 connections) · Groundwater · Local government · EPA ID WI7720165
Data: U.S. EPA · How we read the data · How we check it
Summary
PFAS above the 2024 federal limits. Systems have until 2029 to meet the PFAS limits.
Is it an emergency? No: PFAS limits are about years of exposure, not a glass of water, and nothing in EPA's data calls for you to stop drinking the water today. If your utility ever issues a boil-water or do-not-drink notice, follow it.
- PFAS
- Above limitPFOS above the federal limit in EPA's 2023–2025 testing (PFOS 13 ppt vs a limit of 4 ppt, where ppt = parts per trillion).
- Lead
- Below action level8.2 ppb (parts per billion) at the 90th percentile: 9 in 10 homes sampled were at or below it. Action level 15 ppb, falling to 10 ppb in Nov 2027. Monitoring period ending Dec 2025. Your home's pipes can make yours higher.
- Violations
- Resolved1 health-based violation since 2016, most recently Nov 2020.
- Pregnant, or mixing baby formula with tap water? Babies drink more water for their size, so PFAS exposure matters more for them. Consider bottled water or a filter certified for PFAS for formula, and ask your doctor. Health effects.
- To lower your PFAS exposure now, a home filter certified for PFAS reduction works (reverse osmosis, or activated carbon certified to NSF/ANSI 53 or 58). Filters for these results.
- Built before 1986, or not sure what your service line is made of? Check your service line and test your tap. Utility data can't show your pipes.
- Tested your own tap? Compare your result with these numbers. Moving? Compare this system with another.
- Read Marshfield Utilities's annual water quality report (Consumer Confidence Report). It lists every regulated contaminant tested and is usually on the utility's website or mailed with your bill. EPA: how to find it.
PFAS (“forever chemicals”)
EPA UCMR 5: 3 entry points tested Jan 2023 to Jul 2023. "Average" is the highest entry-point average (non-detects counted as zero), the way EPA compares UCMR 5 results to the limits. ppt = parts per trillion. These results do not determine compliance.
| Contaminant | Highest average |
|---|---|
| PFOA Not detected Limit 4 ppt | – |
| PFOS Above limit Limit 4 ppt | 13 ppt 3.25× the limit |
| PFHxS Rounds to the limit Limit 10 ppt | 12 ppt 1.2× the limit |
| PFNA Not detected Limit 10 ppt | – |
| HFPO-DA (GenX) Not detected Limit 10 ppt | – |
| Hazard Index (a combined score for PFHxS, PFNA, GenX and PFBS, where above 1 is over the limit) Rounds to the limit Limit 1 | 1.2 |
| PFBS Detected, below limit Guideline 2,000 ppt | 1.6 ppt |
| PFBA Detected, below limit Guideline 6,000 ppt | 6.4 ppt |
| PFHxA Detected, below limit Guideline 3,000 ppt | 11.5 ppt |
| PFPeA Detected, no limit | 13.5 ppt |
| PFHpA Detected, no limit | 3.4 ppt |
Why "rounds to the limit"? the PFHxS average (12 ppt) and the Hazard Index (1.2) are slightly above the number on paper, but EPA compares results after rounding to the limit's precision (4.4 ppt rounds to 4), so they meet the limit as EPA applies it. Close enough to the limit to be worth watching.
For context: the PFOS average is higher than at 98% of the Wisconsin systems EPA tested.
29 PFAS tested, 7 detected at least once. "Not detected" means below EPA's reporting limit (about 2 to 20 ppt depending on the chemical), not proven zero. PFAS not listed were not detected. The limits for PFHxS, PFNA, GenX and the Hazard Index were proposed for rescission in May 2026. That proposal is not final. Systems have until 2029 to meet the limits.
Lithium
Not detected in 6 samples (reporting limit 9 ppb). About lithium.
Lead and copper
Latest 90th percentile: 8.2 ppb lead (Jul 2025 – Dec 2025). Below action level
Highest since 2016: 27 ppb (Oct 2020).
| Monitoring period | Lead (90th pct.) |
|---|---|
| Jul 2025 – Dec 2025 | 8.2 ppb |
| Jan 2025 – Jun 2025 | 8.4 ppb |
| Jul 2020 – Oct 2020 | 27 ppb |
Earlier results (9)
| Jun 2019 – Sep 2019 | 4.8 ppb |
| Jun 2016 – Sep 2016 | 5.4 ppb |
| Jun 2013 – Sep 2013 | 9.1 ppb |
| Jan 2010 – Dec 2010 | 9.4 ppb |
| Jan 2009 – Dec 2009 | 7.5 ppb |
| Jul 2008 – Dec 2008 | 10 ppb |
| Jan 2008 – Jun 2008 | 12 ppb |
| Jan 2005 – Dec 2005 | 28 ppb |
| Jan 2002 – Dec 2002 | 11 ppb |
Lead comes from pipes and fixtures, not the source water, so it varies home to home. The 90th percentile means 9 in 10 sampled homes were at or below it. More on lead.
Violations
| When | What happened |
|---|---|
| Nov 2020 | The system did not complete a required study of how to keep lead and copper from dissolving out of pipes. EPA record: Lead and Copper Rule · OCCT/SOWT Study/Recommendation (limit TT ) Resolved |
Health-based violations mean a contaminant exceeded a limit or a required treatment step was missed. Monitoring and reporting violations mean required tests or reports were late or missing, so the water's quality during that time is unknown. The total includes every violation in EPA's records, most of them paperwork.
Earlier EPA testing (2013–2020)
| Contaminant | Highest | Guideline |
|---|---|---|
| Manganese | 57.6 ppb | 300 ppb |
| Chromium-6 | 1.05 ppb | – |
| Chlorate | 580 ppb | 210 ppb |
| Strontium | 0.14 ppm | 1.5 ppm |
| Vanadium | 1.96 ppb | 21 ppb |
Where it serves
Marshfield
ZIP codes the system reported serving: 54449
Nearby utilities
- Oshkosh Waterworks Oshkosh · 21 mi
- Kewaskum Waterworks Kewaskum · 23 mi · PFAS above limit
- Appleton Waterworks Menasha · 27 mi
- Saukville Waterworks Saukville · 32 mi · PFAS above limit
- Hartford Waterworks Hartford · 36 mi · PFAS above limit
- Green Bay Waterworks Green Bay · 48 mi
Questions
Is Marshfield Utilities water safe to drink?
Marshfield Utilities had 1 health-based violation since 2016, all since resolved. EPA testing found PFAS above the 2024 federal limits, which systems must meet by 2029. Federal data can't tell you about your own pipes: lead comes from service lines and plumbing, so test your tap if your home was built before 1986. For the official word, read the utility's annual Consumer Confidence Report.
Does Marshfield Utilities water have PFAS?
Yes. EPA's 2023–2025 testing of Marshfield Utilities found 7 PFAS at least once. The highest entry-point averages were above the federal limit for PFOS: PFOS 13 ppt (limit 4 ppt for PFOA and PFOS, 10 ppt for the others).
What is the lead level in Marshfield Utilities water?
The most recent 90th-percentile lead result for Marshfield Utilities is 8.2 ppb, for the period ending Dec 2025. The federal action level is 15 ppb, falling to 10 ppb in November 2027. The 90th percentile means 9 in 10 homes sampled were at or below this number. Individual homes can be higher.
Check these numbers yourself
Every figure on this page comes from public EPA records. You don't have to take our word for it:
- EPA's own report for WI7720165: violations, enforcement and inspections, straight from EPA.
- EPA UCMR 5 data: the PFAS and lithium results (search the file for PWSID WI7720165).
- EPA SDWIS download: the lead results, population and violation records we use.
- The utility's annual water quality report (Consumer Confidence Report): ask Marshfield Utilities, or see EPA's guide to finding it.
Found something that doesn't match? Tell us and we'll check it against EPA's records. How we check our data.
Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.