Is Tap Water Safe to Drink in Madison?
Yes, tap water in Madison is safe to drink. It comes from about two dozen deep sandstone-aquifer wells and meets all EPA standards. PFAS detections led the utility to shut down one contaminated well rather than serve it, and remaining supply tests low.
Water Source
Madison Water Utility pumps from roughly 20+ deep municipal wells drilled hundreds of feet into the sandstone aquifer beneath the city, disinfecting and adding fluoride with minimal other treatment needed.
EPA Compliance Status
Meets all federal Safe Drinking Water Act standards.
Notable Contaminants & Context
- •PFAS — Well 15 on the east side was taken offline after detections linked to firefighting foam at the Truax Field air base; other wells are routinely monitored and test low or non-detect
- •Naturally occurring iron and manganese at some wells cause occasional discoloration and are managed with filtration at affected sites
- •Road salt (chloride and sodium) is slowly rising in the shallow aquifer, a long-term watch item for a groundwater city
Water Quality Data
Key contaminants detected vs. regulatory limits. All values from the most recent published report — Source: Madison Water Utility 2024 CCR.
| Contaminant | Detected | Limit | Status |
|---|---|---|---|
| Chlorine (total) | 0.6 mg/L | 4.0 mg/L | ✓ |
| Fluoride | 0.72 mg/L | 4.0 mg/L | ✓ |
| Lead (90th percentile) | 1.8 µg/L | 15.0 µg/L | ✓ |
| Nitrate (as N) | 2.7 mg/L | 10.0 mg/L | ✓ |
| TTHM (Total Trihalomethanes) | 10.3 µg/L | 80.0 µg/L | ✓ |
| HAA5 (Haloacetic Acids) | 6.8 µg/L | 60.0 µg/L | ✓ |
✓ = below limit ⚠ = above health goal ✗ = exceeds guideline
How It Compares
Madison's deep groundwater is naturally filtered and needs far less treatment than surface-water systems, though it comes out of the ground much harder than Great Lakes supplies like Milwaukee's.
Tips
- •A softener is common in Madison homes for appliances and taste; the water is safe unsoftened
- •Well-by-well quality data is published by Madison Water Utility, useful since quality varies slightly by neighborhood
- •If you're on the east side, note the utility retired Well 15 specifically to keep PFAS out of the system
Frequently Asked Questions
Sources & References
The safety rating and guidance on this page draw on the following sources. See our full methodology.
- •US EPA Safe Drinking Water Act regulations
- •EWG Tap Water Database
- •The utility's most recent Consumer Confidence Report (CCR)
- •WHO Guidelines for Drinking-water Quality