D
47

Poor Water Quality

Fond Du Lac, WI 54937

Fond Du Lac County · Population served: 50,506 · Data updated March 2026

Water Systems Serving This Area

🌊
NORTH FOND DU LAC WATERWORKS
Groundwater · Pop. 5,014
PWSID: WI4200405
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MARY HILL PARK SANITARY DIST
Groundwater · Pop. 65
PWSID: WI4200465
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FOND DU LAC WATERWORKS
Groundwater · Pop. 44,303
PWSID: WI4200469
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COLONIAL GARDENS HOMES
Groundwater · Pop. 48
PWSID: WI4200484
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ASHWOOD GROVE EDGEWATER
Groundwater · Pop. 1,046
PWSID: WI4200485

Contaminants Detected

ContaminantDetected LevelEPA MCLHealth GuidelineStatus
Lead
12.0
15 ppb 1 ppb Warning

Violation History (Last 5 Years)

136Total (5yr)
2Health-Based
125Major

Water Quality Summary

Understanding Your Water in Fond Du Lac

Tap water quality in Fond Du Lac, Wisconsin (54937) receives an overall grade of D (Poor) with a score of 47 out of 100, based on analysis of EPA compliance data, contaminant testing, and violation history. This is 31 points below the Wisconsin state average of 78. Compared to the national average (75), this area scores significantly lower. The area is served by 6 water systems providing water to approximately 50,506 people, using groundwater sources. Testing has found elevated levels of Lead that warrant attention. Over the past 5 years, water systems here have accumulated 136 violations, including 2 health-based violations.

Your Score 47/100 D
vs State 31 pts below Wisconsin avg (78)
vs National 28 pts below national avg (75)

What a Grade D Means

A score of 47/100 signals poor water quality in Fond Du Lac, WI. Significant issues have been identified, which may include multiple violations, contaminant levels near or above regulatory limits, or PFAS contamination. We recommend reviewing the detailed contaminant data below, considering a certified water filter, and checking your utility's Consumer Confidence Report for the latest information.

Groundwater: drawn from underground aquifers via wells

Health Information

What These Contaminants Mean for You

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Lead in Your Water

Lead is a toxic metal that can leach from aging pipes and plumbing fixtures.

Health Effects

Even low levels of lead exposure can cause developmental delays in children, kidney damage, and cardiovascular effects in adults. The EPA action level is 15 ppb, but health experts recommend no safe level of lead in drinking water.

Common Sources

Lead enters water primarily through corrosion of lead service lines, lead solder, and brass fixtures — especially in homes built before 1986.

What You Can Do

If lead is detected above 1 ppb, consider using a certified lead-removal filter (NSF/ANSI 53) for drinking and cooking water. Run cold water for 30 seconds before use if water has been sitting in pipes.

Common Questions

Frequently Asked Questions

Tap water in Fond Du Lac, Wisconsin receives a grade of D (Poor) with a score of 47/100. This indicates significant water quality concerns based on violation history, contaminant levels, or enforcement actions. We recommend reviewing the specific contaminants detected below and considering a certified water filter.

ZIP code 54937 is served by 6 water systems using groundwater sources, providing water to approximately 50,506 people. Groundwater is naturally filtered through rock and soil, often requiring less treatment. However, it can be vulnerable to contamination from underground sources like naturally occurring arsenic, nitrates from agriculture, or PFAS from industrial sites.

Lead was detected at 12.0 ppb in Fond Du Lac, Wisconsin. While this is below the EPA action level of 15 ppb, it exceeds the health guideline of 1 ppb recommended by health organizations. Consider a certified lead filter, especially if you have young children.

No PFAS ("forever chemicals") were detected in water systems serving Fond Du Lac, Wisconsin during the most recent EPA monitoring period (UCMR5). However, not all water systems have been tested for all PFAS compounds, and new contamination can occur over time.

Water systems serving Fond Du Lac, Wisconsin have received 136 violations in the last 5 years, including 2 health-based violations. Violations can range from paperwork issues (monitoring & reporting) to serious health-based violations where contaminant levels exceeded safe limits. Review the violation details above for specifics.

Based on detected contaminants (lead), residents in Fond Du Lac, Wisconsin should consider: NSF/ANSI 53 certified filter — specifically rated for lead reduction. Pitcher filters (like Brita Longlast or PUR) and under-sink systems both work. Always look for filters with NSF/ANSI certification for the specific contaminants you want to remove.

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