WaterVerge

Is Middleton, WI Tap Water Safe to Drink?

Graded C+, with 5 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

24K residents served 1 water system PWSID: WI1130242
Overall Score
67 / 100
Violations
5 active
Last Updated
May 2026
Source
Groundwater
#364 of 446 in Wisconsin Top 72% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
C+GRADE
Water Quality Grade
67/100
waterverge.com
C+ 67/100

Middleton, WI — Water Quality Report

Middleton's drinking water received a grade of C+ (67 out of 100), indicating fair water quality. The city's 1 water system serves approximately 23,868 residents using groundwater.

Lead levels were measured at 4.0 ppb (90th percentile), well within EPA limits. PFAS testing under UCMR 5 found no detectable forever chemicals.

The system has 33 violations on record, including 3 health-based violations. 5 remain unresolved.

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

What to know about Middleton's water

Middleton ranks #364 out of 446 cities in Wisconsin for water quality, placing it among the lowest-rated in the state.

Middleton 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 1.89 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 30 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
67 out of 100 Grade C+
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
17.8/45
F
Historical violation record including health-based and monitoring violations.
Lead & Copper
18/20
A
Lead at 4.0 ppb (90th percentile).
Contaminants
18.2/20
A
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 Middleton, WI water safe to drink?

Concerns Identified

Middleton's drinking water has significant quality concerns based on EPA testing data. With a grade of C+ (67/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 23,868 residents using groundwater (wells).

5
Active Violations
4.0 ppb
Lead (90th %ile)
None
PFAS Detected
3 events
Disaster History

Recent water quality updates for Middleton

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Middleton's water quality assessment. Grade: C+ (67/100).

Violation
4 drinking water violations recorded

1 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS, Public Notice.

Violation
26 drinking water violations recorded

Contaminants: Chlordane, Simazine, Methoxychlor.

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

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

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Coliform (TCR).

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 Middleton's water supply.

Lead Within Limits
Detected: 4.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Violation history

Middleton's water system has 33 total violations on record, including 3 health-based violations. 5 remain unresolved. 30 violations were issued in the last 5 years.

TTOtherRPTMRMCL
Most recent violations:
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 Public Notice Open
Oct 2024 Public Notice Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Jan 2023 Chlordane 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 Black Earth Creek Nr Brewery, Brewery Creek-Upstream Site-At Cross Plains, Yahara River, Sixmile Creek, Sixmile Creek @ County Trnk Hghwy M Nr Waunakee,Wi.

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 Middleton's water come from?

Middleton's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 23,868 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Black Earth Creek Nr Brewery (river), Brewery Creek-Upstream Site-At Cross Plains (river), Yahara River (river), Sixmile Creek (river), Sixmile Creek @ County Trnk Hghwy M Nr Waunakee,Wi (river).

What Middleton residents can do

Install a water filter

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

Middleton'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
4.0 ppb
EPA Action Level: 15 ppb · 27% of limit
Safe Level
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
3.9 µg/L
EPA MCL: 60 µg/L · 7% of limit
Within LimitUCMR 4 DataHAA6Br: 3.8 µg/LHAA9: 6.6 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
1.89 µg/L
CA MCL (no federal MCL): 10 µg/L · 19% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Detected
79.3 µg/L
EPA Health Ref Level: 1,500 µg/L · 5% of limit
DetectedUCMR 3 Data
Manganese
Inorganic
Elevated
43.6 µg/L
EPA Secondary MCL: 50 µg/L · 87% of limit
DetectedUCMR 4 Data
Vanadium
Inorganic
Detected
0.30 µg/L
EPA Short-term HA: 21 µg/L · 1% of limit
DetectedUCMR 3 Data
Cobalt
Inorganic
Detected
1.24 µg/L
No federal limit: N/A µg/L · 50% of limit
DetectedNo federal MCLUCMR 3 Data
PFAS Testing

Forever chemicals overview

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

Violation summary

33
Total violations
3
Health-based
5
Active / unresolved
Oct 2024
Most recent violation
Compliance Record

Violations & advisories

33 Total
5 Active
3 Health-based
28 Resolved
Violations by category
Synthetic Organic Chemicals
26
Lead and Copper Rule Revisions
2
Public Notice Rule and Revised PN Rule
2
Total Coliform Rule
2
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Treatment Technique
Health-Based Health 0
Oct 2024 Active
Public Notice
Other Violation 0
Oct 2024 Active
Public Notice
Other Violation 0
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Reporting
Reporting 0
Active
Compliance Violation
Monitoring 0
Jan 2023 Resolved
Chlordane
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Jan 2023 Resolved
Simazine
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Jan 2023 Resolved
Methoxychlor
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Jan 2023 Resolved
Diquat
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Jan 2023 Resolved
Glyphosate
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Jan 2023 Resolved
2,4-D
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Jan 2023 Resolved
Pentachlorophenol
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Jan 2023 Resolved
Aldicarb sulfoxide
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Jan 2023 Resolved
Aldicarb sulfone
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Jan 2023 Resolved
Aldicarb
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Jan 2023 Resolved
Heptachlor
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Jan 2023 Resolved
Heptachlor epoxide
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Jan 2023 Resolved
Dinoseb
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Jan 2023 Resolved
Endrin
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Jan 2023 Resolved
BHC-GAMMA
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2023
Showing 20 of 33 violations
Industrial pollution

Top industrial polluters within 10 miles of Middleton

Industrial polluters nearby

Reported releases to surface water by facilities near Middleton, 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
Ammonia94.6 mi
FUTURE FOAM INC
Plastics and Rubber · FUTURE FOAM INC
MIDDLETON, WI53562
1.4 mi
SPRINGS WINDOW FASHIONS LLC
Furniture · SPRINGS WINDOW FASHIONS MANUFACTURING CO USA INC
MIDDLETON, WI53562
0.7 mi
COATING PLACE INC
Chemicals · COATING PLACE INC
VERONA, WI53593
9.0 mi
NORD GEAR CORP
Machinery · NA
WAUNAKEE, WI53597
6.8 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Site context

Superfund sites within 10 miles of Middleton

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) 4.0 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 2.1 ppb from 1992 (6.1 ppb) to 2023 (4.0 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
23,868
Water Systems
1
Water Source

Where Middleton's water comes from

Groundwater

Middleton'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 23,868 people through 1 water system.

Local Hydrology

Water bodies near Middleton

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

Black Earth Creek Nr Brewery
river
Brewery Creek-Upstream Site-At Cross Plains
river
Yahara River
river
Sixmile Creek
river
Sixmile Creek @ County Trnk Hghwy M Nr Waunakee,Wi
river
Infrastructure

Water systems serving Middleton

System Name PWSID Population Source
MIDDLETON WATERWORKS WI1130242 23,868 GW
Regional Comparison

How Middleton compares

Full Wisconsin rankings →

Middleton's score of 67/100 is on par with the average of 65/100 among major Wisconsin cities. It outscores 5 of 10 nearby cities.

Middleton (this city)
67
Milwaukee
90.2
Madison
35.4
Racine
69.5
Kenosha
45.8
Wisconsin avg
65
City Profile

About Middleton, WI

Wikipedia →

Middleton is a city in Dane County, Wisconsin, United States. The population was 21,827 at the 2020 census. A suburb northwest of Madison, it is part of the Madison metropolitan area. Middleton's motto is "The Good Neighbor City."

Economic Profile
$87,333
Median Income
$436,636
Median Home Value
$1,326/mo
Median Rent
2.3%
Unemployment
Community
38.3
Median Age
919
People / sq mi
64.2%
College Educated
48.3%
Homeownership
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Frequently asked questions

Is Middleton, WI tap water safe to drink?

Middleton's water quality earned a grade of C+ (67/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #364 out of 446 cities tested in Wisconsin.

What contaminants are in Middleton's water?

Lead was measured at 4.0 ppb (90th percentile). No PFAS compounds were detected. 33 violations are on record.

How is Middleton'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 Middleton?

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

Where does Middleton's water come from?

Middleton's water is sourced from Groundwater. The city has 1 water system serving approximately 23,868 residents.

What health violations has Middleton's water system had?

Middleton has 3 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. 5 violations remain unresolved.

Is Middleton's groundwater at risk of contamination?

Middleton 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 33 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 Middleton's water compare to other cities?

Middleton ranks #364 out of 446 cities in Wisconsin (better than 18% of state cities) and #11282 out of 15744 cities nationally (28th percentile). The grade of C+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.