COUNTY WATER-SYSTEM LEDGER
Jefferson, Wisconsin
EPA’s September 2026 export lists 6 active community water systems serving Jefferson, Wisconsin, with 3 current-violation flags and 0 serious-violator flags among the covered systems.
Source: EPA SDWIS system-search export · Active community systems serving 2,500+ people · Snapshot 13 Sep 2026
01 / SYSTEMS
Water systems serving Jefferson, Wisconsin
EPA associates 6 covered systems with Jefferson, Wisconsin; their reported population-served values total 57,310 and may overlap.
Ordered by reported population served. Open any record for separate health, monitoring, notice, other, and serious-violator flags.
| Water system | Population served | Primary source | Current export status |
|---|---|---|---|
| Watertown WaterworksWI1280044 | 23,945 | Ground water | No current violation flagged |
| Fort Atkinson WaterworksWI1280103 | 12,390 | Ground water | No current violation flagged |
| Jefferson WaterworksWI1280104 | 7,926 | Ground water | Other current violation flag |
| Lake Mills WaterworksWI1280108 | 6,211 | Ground water | Current monitoring/reporting flag |
| Waterloo WaterworksWI1280115 | 3,520 | Ground water | No current violation flagged |
| Johnson Creek WaterworksWI1280107 | 3,318 | Ground water | Other current violation flag |
02 / SOURCE MIX
Primary water sources for Jefferson, Wisconsin
EPA classifies 6 systems serving Jefferson, Wisconsin across 1 primary-source categories; Ground water is the largest category with 6 systems.
It is the sum of each listed system's reported population served, not a census estimate. Service areas can overlap and some systems list multiple cities or counties.