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WaterSafety

Madison Water Utility

Madison, Wisconsin · PWSID: WI1130224

B
Water Safety Score
87/100
272,000
Population Served
Ground water
Source Type
1
Health Violations
0
Contaminant Exceedances

Detected Contaminants

ContaminantDetected LevelMCL (Limit)StatusSample Date
E. coli (RTCR)0 presence0 presenceWithin LimitOct 17, 2024

Violation History

Contaminant 5200
MonitoringOct 17, 2024 - Dec 13, 2024
Resolved
Enforcement: 2500038
E. coli (RTCR)
ReportingOct 17, 2024 - Present
Open

Frequently Asked Questions

Madison Water Utility has a Water Safety Score of B (87/100). The system serves 272,000 people and has 1 health violation on record. Check the contaminant table above for specific detected substances.

Madison Water Utility has 0 contaminant exceedances above EPA health guidelines. See the full contaminant detection table above for all tested substances and their levels relative to legal limits and health guidelines.

The Water Safety Score (0-100, grades A through F) is based on contaminant levels relative to legal limits, health guideline exceedances, violation history, and enforcement actions. Higher scores indicate fewer concerns.

If your water system has violations, request the Consumer Confidence Report from your utility, consider getting an independent water test from a certified lab, and look into certified water filters for specific contaminants of concern. For lead, run cold water for 30 seconds before drinking.

Sources: EPA SDWIS, EWG Tap Water Database
Last updated:

Water quality data sourced from EPA's Safe Drinking Water Information System (SDWIS). Safety scores are calculated based on contaminant levels, violations, and enforcement history. This is not a substitute for your utility's official Consumer Confidence Report.

The this entity record above pulls directly from the EPA Safe Drinking Water Information System (SDWIS). What follows is the per-entity context — how this entity sits in the broader U.S. public drinking-water safety distribution and which underlying factors drive the headline numbers.

Every number on this page links back to the EPA Safe Drinking Water Information System (SDWIS); the methodology page describes the inputs, refresh cadence, and known limitations of the underlying data product.

Practical use of this page is in combination with the comparison and ranking pages elsewhere on the site, which surface the same data for this entity’s peers within U.S. public water systems. A single-entity reading without peer context can be misleading when an entity is an outlier on one axis but typical on another.

Source: EPA Ground Water and Drinking Water, 2026.