Jefferson County Water Quality: 2 Cities Ranked by the Records
Jefferson County, Wisconsin: 2 city reports built from EPA and utility records. A county has many suppliers; each city shows the system that serves it.
Highest result for each contaminant
One row per contaminant: the highest result any system in the county reported, against its limit. Open a row for the systems behind it.
Lead (90th percentile)Detected in 2 systems15 µg/L federal action level · US EPAHighest13 µg/L
- FORT ATKINSON WATERWORKS13 µg/LMonitoring period: 2023–2023
- WATERTOWN WATERWORKS11 µg/LMonitoring period: 2024–2024
30 substances tested, none detected in any systemShow
Tested in these 2 systems: FORT ATKINSON WATERWORKS, WATERTOWN WATERWORKS
- 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS)
- 1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS)
- 1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS)
- 1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS)
- 4,8-Dioxa-3H-perfluorononanoic acid (ADONA)
- 9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS)
- Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals)
- Lithium
- N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA)
- N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA)
- Nonafluoro-3,6-dioxaheptanoic acid (NFDHA)
- Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA)
- Perfluoro-3-methoxypropanoic acid (PFMPA)
- Perfluoro-4-methoxybutanoic acid (PFMBA)
- Perfluorobutanesulfonic acid (PFBS)
- Perfluorobutanoic acid (PFBA)
- Perfluorodecanoic acid (PFDA)
- Perfluorododecanoic acid (PFDoA)
- Perfluoroheptanesulfonic acid (PFHpS)
- Perfluoroheptanoic acid (PFHpA)
- Perfluorohexanesulfonic acid (PFHxS)
- Perfluorohexanoic acid (PFHxA)
- Perfluorononanoic acid (PFNA)
- Perfluorooctanesulfonic acid (PFOS)
- Perfluorooctanoic acid (PFOA)
- Perfluoropentanesulfonic acid (PFPeS)
- Perfluoropentanoic acid (PFPeA)
- Perfluorotetradecanoic acid (PFTA)
- Perfluorotridecanoic acid (PFTrDA)
- Perfluoroundecanoic acid (PFUnA)
Cities ranked by the records
Ranked by the Purity Score of each city's main water system, highest first. Scores belong to water systems; there is no county score. The score is computed only from contaminants measured in the published EPA record, so this ranks the record, not which city's water is safest. How the score works.
0of 2 cities above the 15 µg/L action level
Based on each system's 90th-percentile result. Lead from household plumbing isn't in this record.
Lead in WisconsinLargest water systems
- WatertownWATERTOWN WATERWORKS · WI128004423,945 served
- Fort AtkinsonFORT ATKINSON WATERWORKS · WI128010312,390 served
Frequently asked
How does Jefferson County tap water compare across cities?
PurityMap ranks 2 cities in Jefferson County by the Purity Score of each city's main water system, computed only from contaminants measured in the published EPA record. Scores belong to water systems, not to cities. The highest published score is Watertown's main water system: WATERTOWN WATERWORKS · PWSID WI1280044 · Purity Score 88 (Good) · Confidence: moderate · Assessed at the water-system level. The ranking compares the records, not which city's water is safest, and your own tap can differ with household plumbing.
How many Jefferson County cities have PFAS above the federal limit?
None of the 2 Jefferson County cities on record had a regulated PFAS above the 2024 federal limit in EPA's UCMR 5 testing. PFAS were detected below the limit in 0.
Is there lead in Jefferson County tap water?
Utilities report lead as a 90th-percentile result from home taps. 2 of 2 Jefferson County cities reported a value above zero, and none was above the 15 µg/L federal action level. Lead usually comes from a building's own pipes and fixtures, so only a test at your tap tells you what you drink.
Follow Jefferson County's water
Get an email when a city record in the county changes.
Record changes only
We email when places in Jefferson County get new results. Unsubscribe any time.
Double opt-in: we email a confirmation link. Unsubscribe anytime. No spam.