Is Wausau, WI Tap Water Safe to Drink?
Graded C — but Chlorate was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
64.7/100
waterverge.com Wausau, WI — Water Quality Report
Wausau's drinking water received a grade of C (64.7 out of 100), indicating fair water quality. The city's 3 water systems serve approximately 46,663 residents using groundwater.
Lead levels were measured at 4.8 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 7 PFAS compounds, with levels exceeding EPA maximum contaminant levels in the water supply.
The system has 61 violations on record, including 24 health-based violations. 29 remain unresolved.
What to know about Wausau's water
Wausau ranks #375 out of 446 cities in Wisconsin for water quality, placing it among the lowest-rated in the state.
Wausau relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.
Of particular concern: PFAS "forever chemical" levels exceed the 2024 EPA maximum contaminant levels. These synthetic compounds don't break down naturally and require specialized filtration such as reverse osmosis or granular activated carbon.
Hexavalent chromium (chromium-6) was detected at 0.16 µg/L in UCMR 3 testing. While below California's 10 µg/L limit and with no federal MCL set, residents sensitive to this contaminant may consider reverse osmosis filtration.
The system has seen 6 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Wausau, WI water safe to drink?
Wausau's drinking water has significant quality concerns based on EPA testing data. With a grade of C (64.7/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 46,663 residents using groundwater (wells).
Recent water quality updates for Wausau
A timeline of significant water quality events, violations, and data updates.
PFAS levels exceed EPA maximum contaminant levels. Reverse osmosis or activated carbon filtration recommended.
Latest EPA compliance and testing data incorporated into Wausau's water quality assessment. Grade: C (64.7/100).
1 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS, Public Notice.
Contaminants: TTHM, Total Haloacetic Acids (HAA5).
1 health-based. Contaminants: Stage 1 Disinfectants and Disinfection Byproducts Rule.
Federal disaster declaration (FEMA DR-3249). Hurricane event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Wausau's water supply.
Well within EPA limits.
PFAS "forever chemicals" exceed EPA maximum contaminant levels. Reverse osmosis or granular activated carbon filtration strongly recommended.
PFAS "forever chemicals" detected
UCMR 5 testing found 7 PFAS compounds in Wausau's water supply. PFAS are synthetic chemicals that persist indefinitely in the environment and the human body.
Violation history
Wausau's water system has 61 total violations on record, including 24 health-based violations. 29 remain unresolved. 6 violations were issued in the last 5 years.
Flood & environmental risk
Marathon County has experienced 2 federally declared disasters since 1973. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Eau Claire River, Wisconsin River.
Where does Wausau's water come from?
Wausau's drinking water comes from groundwater (wells), supplied by 3 water systems serving approximately 46,663 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Eau Claire River (river), Wisconsin River (river).
What Wausau residents can do
Recommended: Reverse osmosis system. This addresses the specific contaminants found in Wausau's water.
Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.
Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Forever chemicals overview
National PFAS report →Violation summary
Violations & advisories
Top industrial polluters within 10 miles of Wausau
Industrial polluters nearby
Reported releases to surface water by facilities near Wausau, ranked by pounds discharged annually.
Total reported releases to surface water: 15,700 lbs
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
DOMTAR PAPER CO LLC ROTHSCHILD, WI54474 | Manganese And Manganese Compounds | 13,394 | 5.3 mi |
BORREGAARD USA INC. ROTHSCHILD, WI54474 | Barium compounds (except for barium sulfate (CAS No. 7727-43-7)) | 1,235 | 5.2 mi |
WESTON POWER PLANT MOSINEE, WI54455 | Barium compounds (except for barium sulfate (CAS No. 7727-43-7)) | 1,019 | 7.3 mi |
KERRY INC. ROTHSCHILD ROTHSCHILD, WI54474 | Nitrate compounds (water dissociable; reportable only when in aqueous solution) | 50 | 6.6 mi |
MERRILL IRON & STEEL INC. SCHOFIELD, WI54476 | Manganese | 3 | 3.9 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Superfund sites within 10 miles of Wausau
Superfund sites nearby
Federally tracked hazardous-waste sites on the EPA National Priorities List. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.
- WAUSAU GROUND WATER CONTAMINATION1.4 mi
Source: EPA Superfund National Priorities List
Flood & disaster history
Marathon County has experienced 2 federally declared disasters since 1973. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in Wausau's water supply, we recommend the following filter types.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 4.8 | 15 | ppb | Inorganic | Safe |
| 11Cl-PF3OUdS | ND | HI | µg/L | PFAS | Not Detected |
| 4:2 FTS | ND | HI | µg/L | PFAS | Not Detected |
| 6:2 FTS 6:2 FTSPFAS A fluorotelomer sulfonate commonly found at sites contaminated with aqueous film-forming foam (AFFF) used in firefighting. Health EffectsPotential liver toxicity and endocrine disruption. Less studied but identified as a contaminant of concern. EPA LimitNo individual MCL (not yet regulated) Common SourcesFirefighting foam (AFFF), airports, military bases, and industrial facilities. | ND | HI | µg/L | PFAS | Not Detected |
| 8:2 FTS | ND | HI | µg/L | PFAS | Not Detected |
| 9Cl-PF3ONS | ND | HI | µg/L | PFAS | Not Detected |
| ADONA | ND | HI | µg/L | PFAS | Not Detected |
| HFPO-DA HFPO-DA (GenX)PFAS A replacement for PFOA in manufacturing, marketed as safer but still a persistent "forever chemical." Also known as GenX. Health EffectsLiver and kidney effects, reproductive toxicity, immune system effects, and potential cancer risk. EPA Limit10 ppt MCL Common SourcesFluoropolymer manufacturing (used as PFOA replacement), industrial wastewater discharge. | ND | 0.01 | µg/L | PFAS | Not Detected |
| lithium LithiumInorganic A naturally occurring alkali metal found in groundwater. Monitored under UCMR 5 to assess occurrence in drinking water. Health EffectsKidney effects at high doses. Low-level exposure effects under study; some research suggests neurological effects. EPA LimitNo MCL (monitoring only under UCMR 5) Common SourcesNatural mineral deposits, geothermal water, and industrial discharge. | ND | HI | µg/L | PFAS | Not Detected |
| NEtFOSAA | ND | HI | µg/L | PFAS | Not Detected |
| NFDHA | ND | HI | µg/L | PFAS | Not Detected |
| NMeFOSAA | ND | HI | µg/L | PFAS | Not Detected |
| PFBA PFBAPFAS One of the shortest-chain PFAS compounds. Very mobile in water and difficult to remove with standard filtration. Health EffectsThyroid effects, potential developmental toxicity. Shorter half-life in body than long-chain PFAS. EPA LimitNo individual MCL (not yet regulated) Common SourcesDegradation of longer-chain PFAS, industrial discharge, and firefighting foam. | 0.016 | HI | µg/L | PFAS | Detected |
| PFBS PFBSPFAS A short-chain PFAS used as a replacement for PFOS. While it clears the body faster than long-chain PFAS, it still persists in the environment. Health EffectsThyroid effects, reproductive and developmental toxicity, kidney effects. EPA LimitPart of Hazard Index (1.0) Common SourcesIndustrial discharge, firefighting foam, and as a replacement chemical in manufacturing. | 0.004 | HI | µg/L | PFAS | Detected |
| PFDA | ND | HI | µg/L | PFAS | Not Detected |
| PFDoA | ND | HI | µg/L | PFAS | Not Detected |
| PFEESA | ND | HI | µg/L | PFAS | Not Detected |
| PFHpA PFHpAPFAS A medium-chain PFAS compound found in various environmental samples. Less studied than PFOA/PFOS but still considered a contaminant of concern. Health EffectsLiver effects, potential developmental toxicity, and endocrine disruption. EPA LimitPart of Hazard Index (1.0) Common SourcesDegradation of longer-chain PFAS, industrial discharge, and contaminated water sources. | ND | HI | µg/L | PFAS | Not Detected |
| PFHpS | ND | HI | µg/L | PFAS | Not Detected |
| PFHxA PFHxAPFAS A short-chain PFAS replacement chemical widely used after manufacturers phased out longer-chain PFAS. Very commonly detected in water. Health EffectsLiver and kidney effects, potential thyroid disruption. Considered less toxic than long-chain PFAS but still persistent. EPA LimitNo individual MCL (not yet regulated) Common SourcesIndustrial processes, firefighting foam (AFFF), food packaging, and textile treatment. | 0.006 | HI | µg/L | PFAS | Detected |
| PFHxS PFHxSPFAS A medium-chain PFAS found in firefighting foam and consumer products. It has a long half-life in the human body, similar to long-chain PFAS. Health EffectsImmune system effects, thyroid disruption, and potential reproductive and developmental harm. EPA LimitPart of Hazard Index (1.0) Common SourcesFirefighting foam (AFFF), waterproof textiles, food packaging, and industrial discharge. | 0.009 | HI | µg/L | PFAS | Detected |
| PFMBA | ND | HI | µg/L | PFAS | Not Detected |
| PFMPA | ND | HI | µg/L | PFAS | Not Detected |
| PFNA PFNAPFAS A long-chain PFAS compound used in manufacturing fluoropolymers. It bioaccumulates in the body and is very persistent in the environment. Health EffectsDevelopmental effects, liver toxicity, immune suppression, and potential cancer risk. EPA LimitPart of Hazard Index (1.0) Common SourcesFluoropolymer manufacturing, industrial emissions, and contaminated water sources. | ND | HI | µg/L | PFAS | Not Detected |
| PFOA PFOAPFAS A long-chain PFAS ("forever chemical") once widely used in nonstick coatings and firefighting foam. It persists in the body and environment for years. Health EffectsLinked to kidney and testicular cancer, thyroid disease, elevated cholesterol, and reproductive issues. EPA Limit4.0 ppt MCL Common SourcesIndustrial discharge, firefighting foam (AFFF), nonstick cookware manufacturing, and contaminated groundwater. | 0.005 | 0.004 | µg/L | PFAS | Over MCL |
| PFOS PFOSPFAS A long-chain PFAS compound historically used in stain-resistant coatings and firefighting foam. One of the most studied and persistent PFAS chemicals. Health EffectsLiver damage, immune system suppression, thyroid disruption, increased cholesterol, and potential cancer risk. EPA Limit4.0 ppt MCL Common SourcesFirefighting foam (AFFF), industrial sites, stain-resistant fabric treatments, and contaminated groundwater. | 0.009 | 0.004 | µg/L | PFAS | Over MCL |
| PFPeA PFPeAPFAS A short-chain PFAS compound commonly detected in drinking water. One of the most frequently found PFAS in UCMR 5 monitoring. Health EffectsLess studied than PFOA/PFOS. Potential liver and thyroid effects. Research is ongoing. EPA LimitNo individual MCL (not yet regulated) Common SourcesIndustrial discharge, firefighting foam degradation, and consumer products. | 0.023 | HI | µg/L | PFAS | Detected |
| PFPeS | ND | HI | µg/L | PFAS | Not Detected |
| PFTA | ND | HI | µg/L | PFAS | Not Detected |
| PFTrDA | ND | HI | µg/L | PFAS | Not Detected |
| PFUnA | ND | HI | µg/L | PFAS | Not Detected |
Lead level trend (90th percentile)
See how Wausau compares by contaminant
Explore where Wausau ranks among all Wisconsin cities for specific contaminants.
Water source & infrastructure
Where Wausau's water comes from
Wausau's drinking water is drawn from underground aquifers through wells.
Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.
Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.
The system is operated by local government ownership and serves approximately 46,663 people through 3 water systems.
Water bodies near Wausau
Wausau is located near 2 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Wausau
| System Name | PWSID | Population | Source |
|---|---|---|---|
| WAUSAU WATERWORKS | WI7370102 | 39,994 | GW |
| RIB MOUNTAIN WATER UTILITY | WI7370660 | 6,398 | GW |
| MAINE WATER UTILITY | WI7370107 | 271 | GW |
How Wausau compares
Full Wisconsin rankings →Wausau's score of 64.7/100 is on par with the average of 65/100 among major Wisconsin cities. It outscores 5 of 10 nearby cities.
Nearby cities
View Wisconsin rankings →About Wausau, WI
Wikipedia →Wausau is a city in Marathon County, Wisconsin, United States, and its county seat. It is located along the Wisconsin River in central Wisconsin and had a population of 39,994 at the 2020 census. The Wausau metropolitan statistical area, consisting solely of Marathon County, had a population of 138,013.
Learn more about your water
Guides and resources related to Wausau's water quality findings.
Explore water quality across Marathon
Frequently asked questions
Is Wausau, WI tap water safe to drink?
Wausau's water quality earned a grade of C (64.7/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #375 out of 446 cities tested in Wisconsin.
What contaminants are in Wausau's water?
Lead was measured at 4.8 ppb (90th percentile). 7 PFAS compounds were detected. 61 violations are on record.
How is Wausau's water quality grade calculated?
The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.
Do I need a water filter in Wausau?
PFAS compounds exceed EPA limits — a reverse osmosis or activated carbon filter is recommended.
Where does Wausau's water come from?
Wausau's water is sourced from Groundwater. The city has 3 water systems serving approximately 46,663 residents.
What health violations has Wausau's water system had?
Wausau has 24 health-based violations on record. The most recent violation was recorded in October 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 29 violations remain unresolved.
Is Wausau's groundwater at risk of contamination?
Wausau uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 61 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.
Why does Wausau have so many PFAS compounds in its water?
7 different PFAS "forever chemical" compounds were detected in Wausau's water supply during UCMR 5 testing. PFAS contamination often originates from proximity to military installations (AFFF firefighting foam), airports, industrial manufacturing sites, or wastewater treatment facilities. Some levels exceed the 2024 EPA maximum contaminant levels — a reverse osmosis or NSF-certified activated carbon filter is strongly recommended.
How does Wausau's water compare to other cities?
Wausau ranks #375 out of 446 cities in Wisconsin (better than 16% of state cities) and #11623 out of 15744 cities nationally (26th percentile). The grade of C reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.