STATE REPORT WI 11 ALERTS 311 HEALTH VIOLATIONS

Wisconsin Water Quality & Safety Report

49 ZIP codes · 142 water systems · State-specific plumbing code · Updated 2026-03-16

Data: EPA SDWIS, NWS, State plumbing boards, Rewiring America Last verified: 2026-03-16

49
ZIP Codes
142
Water Systems
41
ZIPs with Violations
11
Active Alerts
State-specific
Plumbing Code

Overview

We track water quality, weather alerts, plumbing regulations, and energy rebates for 49 ZIP codes across Wisconsin, covering 142 community water systems that serve approximately 2,140,943 people.

41 of 49 ZIP codes (84%) have recorded EPA violations. 311 health-based violations have been documented.

Active Weather Alerts

11 active alerts in Wisconsin including 11 warnings. Severe weather can directly affect tap water quality — flooding, power outages, and infrastructure damage may lead to boil-water advisories.

AlertSeverityAreas
Blizzard WarningExtremeWabasha; Dodge; Olmsted; Winona; Mower; Fillmore; Houston…
Blizzard WarningExtremeLa Crosse; Monroe; Juneau; Adams; Vernon
Blizzard WarningExtremeCrawford; Richland; Grant
Blizzard WarningExtremeLincoln; Langlade; Menominee; Marathon; Shawano; Southern…
Blizzard WarningExtremeKewaunee; Manitowoc

View all Wisconsin alerts →

Plumbing Regulations

Wisconsin follows the Wisconsin Comm 82 Plumbing Code (Current edition).

  • Plumbing code: State-specific (Current)
  • Homeowner DIY: Licensed plumber required
  • Water heater permit: Required
  • Annual backflow test: Required

Full Wisconsin regulations →

Areas with Most Violations

ZIP CodeCitySafety ScoreViolationsHealth-BasedSystem
53090West Bend—3800WEST BEND WATERWORKS
53186Waukesha—302237WAUKESHA WATER UTILITY
53201Milwaukee—770MILWAUKEE WATERWORKS
53140Kenosha—655KENOSHA WATER UTILITY
53094Watertown—364WATERTOWN WATERWORKS
53401Racine—361RACINE WATERWORKS
53010Campbellsport—260CAMPBELLSPORT WATERWORKS
54935Fond Du Lac—262FOND DU LAC WATERWORKS
54729Chippewa Falls—242CHIPPEWA FALLS WATERWORKS
53005Brookfield—221BROOKFIELD WATER UTILITY

Areas with No Violations

ZIP CodeCitySafety ScoreSystemPopulation
53002Allenton—ALLENTON SANITARY DISTRICT860
53011Cascade—CASCADE WATERWORKS719
53012Cedarburg—CEDARBURG L & W COMMISSION11,800
53013Cedar Grove—CEDAR GROVE WATERWORKS2,213
53017Colgate—WILLOW PINES MFD HOME COMMUNITY70
53019Eden—MANOR HILL MOBILE HOME PARK400
53020Elkhart Lake—ELKHART LAKE WATERWORKS1,567
54220Manitowoc—MANITOWOC WATERWORKS34,500

Lead & Copper

  • 0 ZIP codes exceed the EPA lead action level

Radon Risk

  • High risk (Zone 1): 0 ZIP codes (0%)
  • Moderate risk (Zone 2): 0 ZIP codes
  • Low risk (Zone 3): 0 ZIP codes

All 49 ZIP Codes in Wisconsin

Data Sources

Updated daily.

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