WaterVerge

Is Waunakee, WI Tap Water Safe to Drink?

Graded B-, with 20 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

16K residents served 4 water systems PWSID: WI1130265
Overall Score
70.1 / 100
Violations
20 active
Last Updated
May 2026
Source
Groundwater
#346 of 446 in Wisconsin Top 69% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
B-GRADE
Water Quality Grade
70.1/100
waterverge.com
B- 70.1/100

Waunakee, WI — Water Quality Report

Waunakee's drinking water received a grade of B- (70.1 out of 100), indicating fair water quality. The city's 4 water systems serve approximately 15,919 residents using groundwater.

Lead levels were measured at 3.8 ppb (90th percentile), well within EPA limits. PFAS testing under UCMR 5 found no detectable forever chemicals.

The system has 109 violations on record, including 11 health-based violations. 20 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Waunakee's water

Waunakee ranks #346 out of 446 cities in Wisconsin for water quality, placing it among the lowest-rated in the state.

Waunakee 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.

Hexavalent chromium (chromium-6) was detected at 2.39 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 14 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
70.1 out of 100 Grade B-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
24.3/45
D
Historical violation record including health-based and monitoring violations.
Lead & Copper
18/20
A
Lead at 3.8 ppb (90th percentile).
Contaminants
14.8/20
B
No PFAS compounds detected.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Waunakee, WI water safe to drink?

Concerns Identified

Waunakee's drinking water has significant quality concerns based on EPA testing data. With a grade of B- (70.1/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 4 water systems serve approximately 15,919 residents using groundwater (wells).

20
Active Violations
3.8 ppb
Lead (90th %ile)
None
PFAS Detected
3 events
Disaster History

Recent water quality updates for Waunakee

A timeline of significant water quality events, violations, and data updates.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Waunakee's water quality assessment. Grade: B- (70.1/100).

Violation
3 drinking water violations recorded

Contaminants: Public Notice, LEAD AND COPPER RULE REVISIONS, Lead and Copper Rule.

Violation
2 drinking water violations recorded

Contaminants: Total Haloacetic Acids (HAA5), TTHM.

Violation
2 drinking water violations recorded

Contaminants: Consumer Confidence Rule.

Disaster
SEVERE STORMS, TORNADOES, STRAIGHT-LINE WINDS, FLOODING, AND LANDSLIDES

Federal disaster declaration (FEMA DR-4402). Flood event — may have impacted local water infrastructure.

Disaster
HURRICANE KATRINA EVACUATION

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 Waunakee's water supply.

Lead Within Limits
Detected: 3.8 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Violation history

Waunakee's water system has 109 total violations on record, including 11 health-based violations. 20 remain unresolved. 14 violations were issued in the last 5 years.

OtherRPTMRMONMCLTT
Most recent violations:
Oct 2024 Public Notice Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 Lead and Copper Rule Open
Jan 2024 Total Haloacetic Acids (HAA5) Resolved
Jan 2024 TTHM Resolved

Flood & environmental risk

Dane County has experienced 3 federally declared disasters since 1976. 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 Yahara River, Sixmile Creek, Sixmile Creek @ County Trnk Hghwy M Nr Waunakee,Wi, Dorn (Spring) Creek @ Ct Highway Q Nr Waunakee, Dorn (Spring) Creek.

SEVERE STORMS, TORNADOES, STRAIGHT-LINE WINDS, FLOODING, AND LANDSLIDES
Flood FEMA DR-4402
HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3249
SEVERE STORMS, ICING, WIND & FLOODING
Flood FEMA DR-496

Where does Waunakee's water come from?

Waunakee's drinking water comes from groundwater (wells), supplied by 4 water systems serving approximately 15,919 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Yahara River (river), Sixmile Creek (river), Sixmile Creek @ County Trnk Hghwy M Nr Waunakee,Wi (river), Dorn (Spring) Creek @ Ct Highway Q Nr Waunakee (river), Dorn (Spring) Creek (river).

What Waunakee residents can do

Install a water filter

Recommended: NSF-certified water filter. This addresses the specific contaminants found in Waunakee's water.

Request your utility's CCR

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.

Flush your taps

Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.

Monitor alerts during storms

Waunakee's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
3.8 ppb
EPA Action Level: 15 ppb · 25% of limit
Safe Level
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
0.6 µg/L
EPA MCL: 60 µg/L · 1% of limit
Within LimitUCMR 4 DataHAA6Br: 0.3 µg/LHAA9: 0.8 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
2.39 µg/L
CA MCL (no federal MCL): 10 µg/L · 24% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Detected
74.7 µg/L
EPA Health Ref Level: 1,500 µg/L · 5% of limit
DetectedUCMR 3 Data
Manganese
Inorganic
Elevated
40.3 µg/L
EPA Secondary MCL: 50 µg/L · 81% of limit
DetectedUCMR 4 Data
Vanadium
Inorganic
Detected
0.43 µg/L
EPA Short-term HA: 21 µg/L · 2% of limit
DetectedUCMR 3 Data
Chlorate
Disinfection Byproduct
Detected
94.7 µg/L
EPA Lifetime HA: 210 µg/L · 45% of limit
DetectedUCMR 3 Data
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
0
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

109
Total violations
11
Health-based
20
Active / unresolved
Oct 2024
Most recent violation
Compliance Record

Violations & advisories

109 Total
20 Active
11 Health-based
89 Resolved
2 SNC
Violations by category
Synthetic Organic Chemicals
25
Total Coliform Rule
19
Inorganic Chemicals
16
Lead and Copper Rule
12
Radionuclides and Revised Rad Rule
10
Oct 2024 Active
Public Notice
Other Violation 0
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Reporting
Reporting 0
Oct 2024 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2023 Active
Consumer Confidence Rule
Other Violation 0
Jul 2023 Active
Consumer Confidence Rule
Other Violation 0
Jan 2022 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jun 2021 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jun 2015 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Apr 2014 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jan 2012 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jan 2012 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Oct 2009 Active
Consumer Confidence Rule
Other Violation 0
Jan 2009 Active
Public Notice
Other Violation 0
Jul 2008 Active
Lead and Copper Rule
Treatment Technique
Health-Based Health 0
Oct 2004 Active
Public Notice
Other Violation 0
Jul 2000 Active
Consumer Confidence Rule
Other Violation 0
Jan 1994 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 1993 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Showing 20 of 109 violations
Industrial pollution

Top industrial polluters within 10 miles of Waunakee

Industrial polluters nearby

Reported releases to surface water by facilities near Waunakee, ranked by pounds discharged annually.

Total reported releases to surface water: 9 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
MGE WEST CAMPUS COGENERATION FACILITY
Electric Utilities · MGE ENERGY
MADISON, WI53726
Ammonia97.5 mi
HOLCIM SOLUTIONS & PRODUCTS (US) LLC
Plastics and Rubber · HOLCIM PARTICIPATIONS (US) INC
DE FOREST, WI53532
7.3 mi
REG MADISON LLC
Chemicals · CHEVRON CORP
DE FOREST, WI53532
7.3 mi
FRANKLIN ELECTRIC FUELING SYSTEMS
Plastics and Rubber · FRANKLIN ELECTRIC CO
DEFOREST, WI53532
7.6 mi
AMERICAN PACKAGING CORP SITE
Printing · AMERICAN PACKAGING CORP
DEFOREST, WI53532
8.0 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Site context

Superfund sites within 10 miles of Waunakee

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.

Source: EPA Superfund National Priorities List

Environmental Risk

Flood & disaster history

3
Declared disasters
Oct 2018
Most recent
Flood
Most common type

Dane County has experienced 3 federally declared disasters since 1976. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Oct 2018
SEVERE STORMS, TORNADOES, STRAIGHT-LINE WINDS, FLOODING, AND LANDSLIDES
Flood FEMA #4402
Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3249
Mar 1976
SEVERE STORMS, ICING, WIND & FLOODING
Flood FEMA #496

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 3.8 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 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 ND 0.01 µg/L PFAS Not Detected
lithium 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 ND HI µg/L PFAS Not Detected
PFBS ND HI µg/L PFAS Not 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 ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA ND HI µg/L PFAS Not 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
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 0.7 ppb from 1992 (4.5 ppb) to 2024 (3.8 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
15,919
Water Systems
4
Source breakdown
Groundwater
3
Purchased Groundwater
1
Water Source

Where Waunakee's water comes from

Groundwater

Waunakee'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 15,919 people through 4 water systems.

Local Hydrology

Water bodies near Waunakee

Waunakee is located near 5 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Yahara River
river
Sixmile Creek
river
Sixmile Creek @ County Trnk Hghwy M Nr Waunakee,Wi
river
Dorn (Spring) Creek @ Ct Highway Q Nr Waunakee
river
Dorn (Spring) Creek
river
Infrastructure

Water systems serving Waunakee

System Name PWSID Population Source
WAUNAKEE WATERWORKS WI1130265 14,879 GW
WESTPORT WATER UTILITY WI1132442 800 GW
DONS MOBILE MANOR WI1130266 160 GW
WESTPORT BISHOPS BAY AREA WI1134103 80 GWP
Regional Comparison

How Waunakee compares

Full Wisconsin rankings →

Waunakee's score of 70.1/100 is above the average of 65/100 among major Wisconsin cities. It outscores 6 of 10 nearby cities.

Waunakee (this city)
70.1
Milwaukee
90.2
Madison
35.4
Racine
69.5
Kenosha
45.8
Wisconsin avg
65
City Profile

About Waunakee, WI

Wikipedia →

Waunakee is a village in Dane County, Wisconsin, United States. The population was 14,879 at the 2020 census. A suburb of Madison, it is part of the Madison metropolitan area. Waunakee bills itself as "The Only Waunakee in the World".

Economic Profile
$132,305
Median Income
$446,024
Median Home Value
$1,179/mo
Median Rent
1.3%
Unemployment
Community
39.4
Median Age
779
People / sq mi
61.9%
College Educated
77.6%
Homeownership
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Frequently asked questions

Is Waunakee, WI tap water safe to drink?

Waunakee's water quality earned a grade of B- (70.1/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #346 out of 446 cities tested in Wisconsin.

What contaminants are in Waunakee's water?

Lead was measured at 3.8 ppb (90th percentile). No PFAS compounds were detected. 109 violations are on record.

How is Waunakee'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 Waunakee?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Waunakee's water come from?

Waunakee's water is sourced from Groundwater. The city has 4 water systems serving approximately 15,919 residents.

What health violations has Waunakee's water system had?

Waunakee has 11 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. 20 violations remain unresolved.

Is Waunakee's groundwater at risk of contamination?

Waunakee 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 109 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.

How does Waunakee's water compare to other cities?

Waunakee ranks #346 out of 446 cities in Wisconsin (better than 22% of state cities) and #10801 out of 15744 cities nationally (31th percentile). The grade of B- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.