Is Mequon, WI tap water safe?

Data: U.S. EPA · How we read the data · How we check it

No federal limits exceeded in EPA data for Mequon Water Utility.

23 public water systems serve parts of Mequon. The largest, Mequon Water Utility, serves 11,152 people. Your water bill names your system.

Largest system

Mequon Water Utility

11,152 people · Purchased surface water · EPA ID WI2460112

Buys treated water from North Shore Water Commission, Milwaukee Waterworks.

PFAS	Highest average	Limit	Status
PFOA Not detected	–	4 ppt	Not detected
PFOS Not detected	–	4 ppt	Not detected
PFHxS Not detected	–	10 ppt	Not detected
PFNA Not detected	–	10 ppt	Not detected
HFPO-DA (GenX) Not detected	–	10 ppt	Not detected

ppt = parts per trillion. "Highest average" is the highest average at any of the system's entry points, the way EPA compares results with the limits.

Lead: 0.52 ppb at the 90th percentile (Sep 2023, and 9 in 10 homes sampled were at or below it) Below action level
Health-based violations since 2016: 0

Across Wisconsin, 18 of 196 water systems EPA tested had PFAS above a 2024 federal limit, and 4 systems were above the lead action level in results from the last five years. Wisconsin results.

Mequon homes and lead pipes

45%

of homes built before 1980 (Wisconsin 57%, US 50%)

10%

built before 1950 (Wisconsin 23%)

14%

of households rent (Wisconsin 32%)

Lead service lines and lead solder were allowed until 1986, so homes from before then are the ones to check. How to check your own line.

Housing: Census American Community Survey 2020–2024 5-year estimates for Mequon city (tables B25034, B25003). Estimates for small places have a margin of error.

Other water systems serving Mequon

Concordia University Water System
1,500 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
Mequon Trail Townhomes Water System
615 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sampleAlso: 1 health-based violation since 2016
Huntington Park Water System
600 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
Beechwood Farms Estates Water System
300 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
Westchester Lakes Subdivision
300 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
Park Place Subdivision
260 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample

16 more systems

Brighton Ridge Subdivision
200 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
Pines Subdivision
200 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sampleAlso: 1 health-based violation since 2016
Haddonstone Subdivision
195 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
Country Terrace Condo Homes Water System
160 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
Vintage Estates Water System
130 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sampleAlso: 1 health-based violation since 2016
Kenilworth Subdivision
120 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
Mequon on the Square Condominium Owners Association Inc
110 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
Ravine Farms Home Owners Association
100 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
River Lake Subdivision
100 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
Wyngate Subdivision
100 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
Woodridge Estates Water System
100 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
Highland Colony Estates Condo Water System
88 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
River Trails Estates Water Users
84 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sampleAlso: 1 health-based violation since 2016
Mequon Colony Estates Water System
75 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
Mequon Parc Apartments LLC
60 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sample
Mequon Water Trust
26 people · Groundwater · Wisconsin · lists this city
Not in EPA's PFAS sampleAlso: 1 health-based violation since 2016

How nearby cities compare

City	Main water system	PFAS	Lead (90th pct.)
Menomonee Falls 6 mi Menomonee Falls Water Works – Surface Water	Menomonee Falls Water Works – Surface Water	None above limits	2.1 ppb
Wauwatosa 10 mi Wauwatosa Waterworks	Wauwatosa Waterworks	None above limits	8.4 ppb
Milwaukee 10 mi Milwaukee Waterworks	Milwaukee Waterworks	None above limits	5.3 ppb
Brookfield 11 mi Brookfield Water Utility	Brookfield Water Utility	None above limits	1.5 ppb
West Allis 14 mi West Allis Waterworks	West Allis Waterworks	None above limits	2.4 ppb
West Bend 17 mi West Bend Waterworks	West Bend Waterworks	None above limits	5.8 ppb

Mequon ZIP codes (2)

53092
53097

Questions

Is Mequon tap water safe to drink?

Mequon Water Utility has had no health-based violations since 2016. Utility data can't show lead from your own pipes: if your home was built before 1986, test your tap. Your utility's annual Consumer Confidence Report is the official summary.

Who supplies water in Mequon, WI?

23 public water systems serve parts of Mequon. The largest is Mequon Water Utility (11,152 people). Your water bill names your system. The EPA ID is also on your utility's Consumer Confidence Report.

Does Mequon tap water have PFAS?

None detected above EPA's reporting limits. Mequon Water Utility had no PFAS detected in EPA's 2023–2025 testing. "Not detected" means below the reporting limit (about 2 to 20 ppt), not proven zero.

Do Mequon homes have lead pipes?

Census estimates put 45% of Mequon homes as built before 1980 (Wisconsin: 57%). Lead service lines and lead solder were allowed until 1986, so older homes are more likely to have them. Mequon Water Utility's service line inventory says what your line is made of. The only way to know for your home is to check the line where it enters the house and test your tap.

Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.