WaterVerge

Is Grafton, WI Tap Water Safe to Drink?

Graded C+ — but Strontium and 1,4-Dioxane were detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

12K residents served 3 water systems PWSID: WI2460111
Overall Score
65.2 / 100
Violations
18 active
Last Updated
May 2026
Source
Groundwater
#371 of 446 in Wisconsin Top 73% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
C+GRADE
Water Quality Grade
65.2/100
waterverge.com
C+ 65.2/100

Grafton, WI — Water Quality Report

Grafton's drinking water received a grade of C+ (65.2 out of 100), indicating fair water quality. The city's 3 water systems serve approximately 12,469 residents using groundwater.

Lead levels were measured at 0.7 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.

The system has 167 violations on record, including 12 health-based violations. 18 remain unresolved.

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

What to know about Grafton's water

Grafton ranks #371 out of 446 cities in Wisconsin for water quality, placing it among the lowest-rated in the state.

Grafton 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.

PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.

Hexavalent chromium (chromium-6) was detected at 0.06 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 8 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
65.2 out of 100 Grade C+
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
19.7/45
F
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.7 ppb (90th percentile).
Contaminants
12.5/20
C
1 PFAS compound detected.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Grafton, WI water safe to drink?

Concerns Identified

Grafton's drinking water has significant quality concerns based on EPA testing data. With a grade of C+ (65.2/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 12,469 residents using groundwater (wells).

18
Active Violations
0.7 ppb
Lead (90th %ile)
1 compound
PFAS Detected
5 events
Disaster History

Recent water quality updates for Grafton

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

PFAS
1 PFAS "forever chemical" compound detected

Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Grafton's water quality assessment. Grade: C+ (65.2/100).

Violation
1 drinking water violation recorded

Contaminants: LEAD AND COPPER RULE REVISIONS.

Violation
4 drinking water violations recorded

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

Violation
1 drinking water violation recorded

Contaminants: Lead and Copper 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.

Key contaminant findings

Based on the most recent EPA sampling data for Grafton's water supply.

Lead Within Limits
Detected: 0.7 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

PFAS (1 compound) Elevated
Detected: Highest: lithium at 9.0000 µg/L Limit: 0.004 µg/L (EPA MCL)

Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.

Violation history

Grafton's water system has 167 total violations on record, including 12 health-based violations. 18 remain unresolved. 8 violations were issued in the last 5 years.

RPTTTOtherMRMCL
Most recent violations:
Jul 2025 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 LEAD AND COPPER RULE REVISIONS Open
Oct 2024 Public Notice Open
Oct 2024 Public Notice Open

Flood & environmental risk

Ozaukee County has experienced 5 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 Cedar Creek, Milwaukee River, Little Menomonee River.

SEVERE STORMS, TORNADOES, STRAIGHT-LINE WINDS, FLOODING, AND LANDSLIDES
Flood FEMA DR-4402
HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3249
SEVERE STORMS & FLOODING
Flood FEMA DR-775

Where does Grafton's water come from?

Grafton's drinking water comes from groundwater (wells), supplied by 3 water systems serving approximately 12,469 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Cedar Creek (river), Milwaukee River (river), Little Menomonee River (river).

What Grafton residents can do

Install a water filter

Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in Grafton'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.

Monitor alerts during storms

Grafton'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
0.7 ppb
EPA Action Level: 15 ppb · 5% of limit
Safe Level
lithium
PFAS / Forever Chemical
Near MCL
9.0000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
3.2 µg/L
EPA MCL: 60 µg/L · 5% of limit
Within LimitUCMR 4 DataHAA6Br: 5.6 µg/LHAA9: 7.3 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
0.06 µg/L
CA MCL (no federal MCL): 10 µg/L · 1% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Over HRL
4009.3 µg/L
EPA Health Ref Level: 1,500 µg/L · +20% over limit
Over HRLUCMR 3 Data
1,4-Dioxane
Organic
Over HA
2.37 µg/L
EPA Health Advisory: 0.35 µg/L · +20% over limit
Over Health AdvisoryUCMR 3 Data
Manganese
Inorganic
Elevated
30.7 µg/L
EPA Secondary MCL: 50 µg/L · 61% of limit
DetectedUCMR 4 Data
Chlorate
Disinfection Byproduct
Elevated
143.5 µg/L
EPA Lifetime HA: 210 µg/L · 68% of limit
DetectedUCMR 3 Data
Molybdenum
Inorganic
Detected
2.63 µg/L
EPA Lifetime HA: 40 µg/L · 7% of limit
DetectedUCMR 3 Data
Lithium
Inorganic
Detected
9.0 µg/L
State screening level: 60 µg/L · 15% of limit
DetectedNo federal MCLUCMR 5 Data (2023–2025)
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
1
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

167
Total violations
12
Health-based
18
Active / unresolved
Jul 2025
Most recent violation
Compliance Record

Violations & advisories

167 Total
18 Active
12 Health-based
149 Resolved
Violations by category
Volatile Organic Chemicals
126
Total Coliform Rule
12
Arsenic Rule
7
Public Notice Rule and Revised PN Rule
6
Lead and Copper Rule
5
Jul 2025 Active
LEAD AND COPPER RULE REVISIONS
Reporting
Reporting 0
Oct 2024 Active
LEAD AND COPPER RULE REVISIONS
Reporting
Reporting 0
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
Jan 2022 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jun 2021 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Feb 2020 Active
Public Notice
Other Violation 0
Jan 2020 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Sep 2019 Active
Public Notice
Other Violation 0
Sep 2019 Active
Public Notice
Other Violation 0
Jun 2018 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Apr 2004 Active
Public Notice
Other Violation 0
Jul 2002 Active
Consumer Confidence Rule
Other Violation 0
Jan 1999 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Jan 2021 Resolved
Nitrite
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2021
Oct 2020 Resolved
Arsenic
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2020
Showing 20 of 167 violations
Industrial pollution

Top industrial polluters within 10 miles of Grafton

Industrial polluters nearby

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

Total reported releases to surface water: 374 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
SCHREIBER FOODS
Food · SCHREIBER FOODS INC
WEST BEND, WI53095
Nitrate compounds (water dissociable; reportable only when in aqueous solution)1996.9 mi
CHARTER STEEL-SAUKVILLE
Primary Metals · CHARTER MANUFACTURING CO INC
SAUKVILLE, WI53080
Manganese compounds1755.3 mi
CARLSON TOOL & MANUFACTURING CORP.
Machinery · NA
CEDARBURG, WI53012
3.3 mi
KEMPS LLC
Food · DAIRY FARMERS OF AMERICA INC
CEDARBURG, WI53012
3.1 mi
PERFORMANCE HEALTH SUPPLY INC
Plastics and Rubber · PERFORMANCE HEALTH & WELLNESS HOLDINGS INC
CEDARBURG, WI53012
3.6 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Site context

Superfund sites within 10 miles of Grafton

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

5
Declared disasters
Oct 2018
Most recent
Flood
Most common type

Ozaukee County has experienced 5 federally declared disasters since 1973. 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
Oct 1986
SEVERE STORMS & FLOODING
Flood FEMA #775
Mar 1976
SEVERE STORMS, ICING, WIND & FLOODING
Flood FEMA #496
Apr 1973
SEVERE STORMS & FLOODING
Flood FEMA #376

Recommended water filters

Based on contaminants detected in Grafton's water supply, we recommend the following filter types.

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
1 PFAS compound detected

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.7 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 9.000 HI µg/L PFAS 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 6.6 ppb from 1992 (8.0 ppb) to 2024 (1.4 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
12,469
Water Systems
3
Water Source

Where Grafton's water comes from

Groundwater

Grafton'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 12,469 people through 3 water systems.

Local Hydrology

Water bodies near Grafton

Grafton is located near 3 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Cedar Creek
river
Milwaukee River
river
Little Menomonee River
river
Infrastructure

Water systems serving Grafton

System Name PWSID Population Source
GRAFTON WATERWORKS WI2460111 12,269 GW
OSPREY MOBILE HOME PARK WI2460113 150 GW
STONECROFT CONDOMINIUM ASSN WI2460114 50 GW
Regional Comparison

How Grafton compares

Full Wisconsin rankings →

Grafton's score of 65.2/100 is on par with the average of 65/100 among major Wisconsin cities. It outscores 5 of 10 nearby cities.

Grafton (this city)
65.2
Milwaukee
90.2
Madison
35.4
Racine
69.5
Kenosha
45.8
Wisconsin avg
65
City Profile

About Grafton, WI

Wikipedia →

Grafton is a village in Ozaukee County, Wisconsin, United States. Located about 20 miles (32 km) north of Milwaukee and in close proximity to Interstate 43, it is a suburban community in the Milwaukee metropolitan area. The village incorporated in 1896, and at the time of the 2020 census the population was 12,094.

Economic Profile
$83,500
Median Income
$281,325
Median Home Value
$1,109/mo
Median Rent
2%
Unemployment
Community
43.8
Median Age
919
People / sq mi
44%
College Educated
63.3%
Homeownership
Share this reportHelp others learn about their water quality
WhatsAppXFacebookLinkedInEmail

Frequently asked questions

Is Grafton, WI tap water safe to drink?

Grafton's water quality earned a grade of C+ (65.2/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #371 out of 446 cities tested in Wisconsin.

What contaminants are in Grafton's water?

Lead was measured at 0.7 ppb (90th percentile). 1 PFAS compound was detected. 167 violations are on record.

How is Grafton'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 Grafton?

PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.

Where does Grafton's water come from?

Grafton's water is sourced from Groundwater. The city has 3 water systems serving approximately 12,469 residents.

What health violations has Grafton's water system had?

Grafton has 12 health-based violations on record. The most recent violation was recorded in July 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 18 violations remain unresolved.

Is Grafton's groundwater at risk of contamination?

Grafton 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 167 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 Grafton's water compare to other cities?

Grafton ranks #371 out of 446 cities in Wisconsin (better than 17% of state cities) and #11547 out of 15744 cities nationally (27th percentile). The grade of C+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.