Drinking water quality · 2024
· Verified
· PWSID WI1130235
What's in Madison, WI tap water
Every one of the 12 core regulated contaminants reported for Madison, WI came in below its federal limit.
- !1 open monitoring or reporting violation
- !12 of 27 core regulated contaminants reported — 15 never appear in this report
- ✓Nothing over a federal limit
+How this score is calculated
Every system starts at 100. Points come off for measured levels, for the federal violation record, and for how much of the core regulated set the utility actually reported. All three inputs are the utility's own published numbers and EPA's own records.
- −0 contaminants at or above a federal limit
- −0 contaminants within 20% of a limit
- −0 open health-based violations
- −3 open monitoring / reporting violations
- −0 health-based violations resolved in the last 5 years
- −11 core regulated contaminants never reported (12/27)
A 90–100 · B 80–89 · C 70–79 · D 60–69 · F below 60. A system reporting under a third of the core set is capped at C however clean its numbers look — a short report is not a clean bill of health.
Full grading methodology, constant for constant →+30 contaminants were measured and came in below the limitShow all
| Contaminant | Measured | Federal limit |
|---|---|---|
| Perfluorohexanesulfonic acid | 6.6–7.3 ng/L | 10 ng/L |
| Radium 226 228 | 2.4 pCi/L | 5 pCi/L |
| Lead | 0.0032 mg/L | 0.015 mg/L |
| Fluoride | 0.7 mg/L | 4 mg/L |
| Copper | 150 ug/L | 1300 ug/L |
| Nitrate | 0.9 mg/L | 10 mg/L |
| Gross Alpha | 1.3 pCi/L | 15 pCi/L |
| TTHM | 5.5 ug/L | 80 ug/L |
| HAA5 | 1.5 ug/L | 60 ug/L |
| Barium | 21 ug/L | 2000 ug/L |
| Chloride | 16 mg/L | — |
| Sulfate | 18 mg/L | — |
| Chromium, Hexavalent | 0.4 ug/L | — |
| Chromium, Total | Not detected ug/L | 100 ug/L |
| Iron | Not detected mg/L | — |
| Manganese | 2.5 ug/L | — |
| Nickel | Not detected ug/L | — |
| Selenium | Not detected ug/L | 50 ug/L |
| Sodium | 7.3 mg/L | — |
| Strontium | 82 ug/L | — |
| Zinc | 3.8 ug/L | — |
| Cis Dichloroethylene 12 | Not detected ug/L | 70 ug/L |
| Dichloroethane 12 | Not detected mg/L | 0.005 mg/L |
| Dichloroethylene 11 | Not detected ug/L | 7 ug/L |
| Pce | Not detected ug/L | 5 ug/L |
| Tce | Not detected ug/L | 5 ug/L |
| PFBA | 36–47 ng/L | — |
| PFOA | Not detected ng/L | 4 ng/L |
| PFOS | Not detected ng/L | 4 ng/L |
| Atrazine | Not detected ug/L | 3 ug/L |
What this report doesn't tell you
15 of the 27 contaminants a community water system normally reports do not appear anywhere in Madison, WI's data. Absent is not the same as absent-from-the-water — it means nobody published a number.
+Full detail: PFAS testing, water source, historical monitoring, and the federal violation record
Where your water comes from · EPA SDWIS
Madison, WI's drinking water comes from ground water, drawn from 2 sources.
Source
- YP894
- YP889
Treatment
- YP894
- YP889
Distribution
Compliance history
Federal Safe Drinking Water Act violation & enforcement records (EPA SDWIS). A violation is a regulatory determination by the state or EPA — separate from the measured levels above.
- Treatment technique violationHealth-based1 violation on record · most recent Jan 2012resolved
- Other1 violation on record · most recent Jan 20121 open
Source: EPA SDWIS / ECHO. View the full federal record on EPA ECHO ↗