County · Wisconsin
Dane County, Wisconsin: drinking water records
This overview covers 35 ZIP codes and 43 community water systems in Dane County. It also stands in for 0 ZIP codes whose utility has too little EPA data for a page of its own.
System population figures are summed from EPA registry records and can overlap where wholesalers and retail systems serve the same people. They are not a Census county-population estimate.
Water systems with the most complete records
| Water system | People served | PFAS survey results | PFAS found | Health-based violations | Lead, 9 in 10 homes at or below |
|---|---|---|---|---|---|
| Madison Water Utility WI1130224 | 272,000 | 1,200 | 2 | 1 | 1.8 ppb |
| Sun Prairie Utilities WI1130258 | 39,300 | 420 | 0 | 1 | 2.8 ppb |
| Middleton Waterworks WI1130242 | 23,868 | 360 | 0 | 1 | 4 ppb |
| Verona Waterworks WI1130259 | 14,030 | 300 | 1 | 1 | 2.9 ppb |
| Deforest Waterworks WI1130221 | 10,500 | 240 | 0 | 1 | 6.0 ppb |
| Cottage Grove Waterworks WI1130218 | 9,345 | 180 | 0 | 1 | 2.3 ppb |
| Marshall Waterworks WI1130237 | 3,862 | 180 | 0 | 1 | 0.3 ppb |
| Fitchburg Utility Dist 1 WI1130231 | 24,500 | 240 | 0 | 0 | 2.3 ppb |
| Waunakee Waterworks WI1130265 | 14,879 | 240 | 0 | 0 | 1.7 ppb |
| Stoughton Waterworks WI1130078 | 13,078 | 240 | 1 | 0 | 4.2 ppb |
| Oregon Waterworks WI1130251 | 11,200 | 180 | 0 | 0 | 5.0 ppb |
| Mcfarland Waterworks WI1130241 | 9,676 | 180 | 1 | 0 | 2.1 ppb |
| Monona Waterworks WI1130245 | 8,624 | 180 | 5 | 0 | 2.8 ppb |
| Mt Horeb Waterworks WI1130247 | 7,756 | 240 | 2 | 0 | 3 ppb |
| Cross Plains Waterworks WI1130219 | 4,100 | 180 | 0 | 0 | 4.8 ppb |
| Cambridge Water & Sewer Utility WI1130074 | 1,638 | 0 | 0 | 1 | 1.2 ppb |
| Black Earth Waterworks WI1130211 | 1,493 | 0 | 0 | 1 | 2.4 ppb |
| Oakhill Correctional Inst WI1130250 | 1,096 | 0 | 0 | 1 | 0 ppb |
| Lake Forest Water Coop WI1130232 | 400 | 0 | 0 | 2 | 8.1 ppb |
| Country Vineyard 4 WI1130603 | 28 | 0 | 0 | 1 | 7.5 ppb |
| Windsor Water Utility South WI1130267 | 4,607 | 0 | 0 | 0 | 5.5 ppb |
| Mendota Mental Health Inst WI1130235 | 2,787 | 0 | 0 | 0 | 7 ppb |
| Deerfield Waterworks WI1130223 | 2,510 | 0 | 0 | 0 | 1.7 ppb |
| Mazomanie Waterworks WI1130239 | 1,744 | 0 | 0 | 0 | 0 ppb |
| Shorewood Hills Waterworks WI1130236 | 1,670 | 0 | 0 | 0 | 1.7 ppb |
ZIP reports in Dane County
No ZIP report in this county is published yet.
Sources and scope
EPA UCMR 5 occurrence data, samples collected 2023-01-03 – 2026-06-17, final release, August 2026 (file dated Aug 28, 2026); EPA SDWIS via ECHO, 2026Q2 extract (file dated Jul 9, 2026); EPA service-area boundaries v3.0; Census 2020 ZCTAs. Page generated 2026-09-03.
Counts cover the systems that report this county to EPA. A water system may cross county lines. "Found" means at least one result at or above the laboratory reporting level; it is not a compliance finding.