Tap Water Results

Is Waukesha, WI tap water safe?

Supplied by Waukesha Water Utility · serves 70,718 people (26,192 connections) · Purchased surface water · EPA ID WI2680238

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

Most of Waukesha gets its water from Waukesha Water Utility. Parts of the city are served by a smaller system: Schoenstatt Sisters of Mary Water System (80 people). Your water bill names your system.

Buys water from Milwaukee Waterworks. Treated water bought from another system can carry that system's contaminants.

Summary

No federal limits exceeded in EPA data.

PFAS
Not detectedNone of 29 PFAS found above EPA's reporting limits in 14 samples (2023–2025).
Lead
Below action level0.56 ppb (parts per billion) at the 90th percentile: 9 in 10 homes sampled were at or below it. Action level 15 ppb, falling to 10 ppb in Nov 2027. Monitoring period ending Dec 2024. Your home's pipes can make yours higher.
Violations
Resolved160 health-based violations since 2016, most recently Oct 2023.
What you can do

PFAS (“forever chemicals”)

EPA UCMR 5: 7 entry points tested Feb 2023 to Aug 2023. "Average" is the highest entry-point average (non-detects counted as zero), the way EPA compares UCMR 5 results to the limits. ppt = parts per trillion. These results do not determine compliance.

ContaminantHighest averageHighest resultLimitStatus
PFOA
Not detected
Limit 4 ppt
––4 pptNot detected
PFOS
Not detected
Limit 4 ppt
––4 pptNot detected
PFHxS
Not detected
Limit 10 ppt
––10 pptNot detected
PFNA
Not detected
Limit 10 ppt
––10 pptNot detected
HFPO-DA (GenX)
Not detected
Limit 10 ppt
––10 pptNot detected
Hazard Index (a combined score for PFHxS, PFNA, GenX and PFBS, where above 1 is over the limit)
Not detected
Limit 1
––1Not detected
PFBS
Not detected
Guideline 2,000 ppt
––2,000 ppt guidelineNot detected
PFBA
Not detected
Guideline 6,000 ppt
––6,000 ppt guidelineNot detected
PFHxA
Not detected
Guideline 3,000 ppt
––3,000 ppt guidelineNot detected

29 PFAS tested, 0 detected at least once. "Not detected" means below EPA's reporting limit (about 2 to 20 ppt depending on the chemical), not proven zero. PFAS not listed were not detected. The limits for PFHxS, PFNA, GenX and the Hazard Index were proposed for rescission in May 2026. That proposal is not final. Systems have until 2029 to meet the limits.

Lithium

Not detected in 14 samples (reporting limit 9 ppb). About lithium.

Lead and copper

Latest 90th percentile: 0.56 ppb lead (Jul 2024 – Dec 2024). Below action level

Highest since 2016: 2.3 ppb (Sep 2023).

Monitoring periodLead (90th pct.)
Jul 2024 – Dec 20240.56 ppb
Jan 2024 – Jun 20240.88 ppb
Jun 2023 – Sep 20232.3 ppb
Earlier results (9)
Jul 2020 – Oct 20202.1 ppb
Jun 2017 – Sep 20171.55 ppb
Jun 2014 – Sep 20142.6 ppb
Jun 2011 – Sep 20112.8 ppb
Jan 2008 – Dec 20083.1 ppb
Jan 2005 – Dec 20053.7 ppb
Jan 2002 – Dec 20024.4 ppb
Jul 1999 – Dec 19993.2 ppb
Jul 1998 – Dec 19983.4 ppb

Lead comes from pipes and fixtures, not the source water, so it varies home to home. The 90th percentile means 9 in 10 sampled homes were at or below it. More on lead.

Violations

160
Health-based since 2016
0
Monitoring/reporting since 2016
0
Health-based unresolved now (plus 2 paperwork)
382
Total ever recorded, incl. paperwork
WhenWhat happenedStatus
Jan 2021 – Oct 2023
32 times
The running annual average for Combined Radium (-226 and -228) was above the legal limit.
EPA record: Combined Radium (-226 and -228) · Maximum Contaminant Level Violation, Average · measured 7.79 pci/l (limit 5 pCi/L)
Resolved
Resolved
Jan 2021 – Apr 2023
26 times
The running annual average for Gross Alpha, Excl. Radon and U was above the legal limit.
EPA record: Gross Alpha, Excl. Radon and U · Maximum Contaminant Level Violation, Average · measured 16.9 pci/l (limit 15 pCi/L)
Resolved
Resolved

2 unresolved monitoring or reporting violations: Public Notice.

Health-based violations mean a contaminant exceeded a limit or a required treatment step was missed. Monitoring and reporting violations mean required tests or reports were late or missing, so the water's quality during that time is unknown. The total includes every violation in EPA's records, most of them paperwork.

Earlier EPA testing (2013–2020)

ContaminantHighestGuidelineDetectedTested
Manganese62.9 ppb300 ppb11 of 14UCMR 4 (2020)
Strontium39 ppm1.5 ppm16 of 16UCMR 3 (2015)
Molybdenum1.33 ppb40 ppb3 of 16UCMR 3 (2015)
Chlorate222 ppb210 ppb12 of 16UCMR 3 (2015)

Where it serves

Waukesha

ZIP codes the system reported serving: 53186, 53187, 53188, 53189

Nearby utilities

Questions

Is Waukesha tap water safe to drink?

Most of Waukesha gets its water from Waukesha Water Utility. Waukesha Water Utility had 160 health-based violations since 2016, all since resolved. EPA testing found no PFAS above the federal limits. Federal data can't tell you about your own pipes: lead comes from service lines and plumbing, so test your tap if your home was built before 1986. For the official word, read the utility's annual Consumer Confidence Report.

Does Waukesha water have PFAS?

EPA tested Waukesha Water Utility for 29 PFAS between Feb 2023 and Aug 2023 and none were detected above the reporting limits (about 2 to 20 ppt depending on the chemical).

What is the lead level in Waukesha water?

The most recent 90th-percentile lead result for Waukesha Water Utility is 0.56 ppb, for the period ending Dec 2024. The federal action level is 15 ppb, falling to 10 ppb in November 2027. The 90th percentile means 9 in 10 homes sampled were at or below this number. Individual homes can be higher.

Check these numbers yourself

Every figure on this page comes from public EPA records. You don't have to take our word for it:

Found something that doesn't match? Tell us and we'll check it against EPA's records. How we check our data.

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