States ›Wisconsin ›Jefferson County ›Koshkonong

Koshkonong, WI Tap Water Quality 2026

Water quality report for Koshkonong, WI — PFAS, lead and copper results, violation history and state inspection findings from EPA SDWIS.

A look at Koshkonong's drinking water using EPA enforcement records: violations, lead and copper results, PFAS sampling and state inspection findings.

Main Utility: Fort Atkinson Waterworks PWSID: WI1280103 Updated: 2026 Q2
✅

No federal limits exceeded on record

Lead is 13.00 ppb, 87% of the action level and no violations are open. No PFAS was detected.

B

Koshkonong earns a B for water quality

Graded on violations, lead, and PFAS, with state inspection findings.

Lead: 13.00 ppb — 87% of the federal action level
PFAS tested, none detected
No violations since 2015
No violations currently open
Koshkonong's lead level vs. all Wisconsin community water systems
0 ppb5 ppb10 ppb15 ppb
Lead level: 13.00 ppb — 87% of the federal action level
✓ Lower lead than 3% of Wisconsin utilities
Population Served
467
~4588 connections
Water Source
Groundwater
Drawn from wells — SDWIS source code GW
Active Violations
0
None on record since 2015

Lead & Copper Testing

Lead (Pb)
90th percentile of tap samples collected across the distribution system
87% of EPA action level
13.00 ppb
Action level: 15 ppb
The 90th-percentile lead result is 13.00 ppb, 87% of the 15 ppb federal action level. The action level is a treatment trigger, not a legal maximum, and it is measured across sampled taps rather than at any single home.

Contaminant Violations (2015–Present)

✓ No violations on record for this water system.
Understanding violation types MCL violations mean a contaminant exceeded the federal maximum limit — the most serious type.
TT (Treatment Technique) violations mean required treatment procedures weren't followed, but don't necessarily mean contamination occurred.

Violation History

No violations are on record for this system since 2015. EPA records violations for every community water system, so this reflects a clean compliance history rather than missing data.

About the Main Water System

Utility Fort Atkinson Waterworks
PWSID WI1280103
Water source Groundwater — Drawn from wells — SDWIS source code GW
Population served 467
Service connections 4,588
Systems serving this area 3
Regulator State primacy agency
Data through 2026 Q2 — EPA SDWIS

Frequently Asked Questions

Is Koshkonong tap water safe to drink? ▼
No federal limit is exceeded on record. No violations are currently open. Lead is 13.00 ppb, 87% of the action level.
Does Koshkonong water have PFAS? ▼
It was tested for the six regulated PFAS compounds and none were detected.
Who supplies water to Koshkonong? ▼
Fort Atkinson Waterworks (PWSID WI1280103), one of 3 systems serving this area. Groundwater. Drawn from wells — SDWIS source code GW
When was this system last inspected? ▼
It was last inspected on 2025-06-05. Inspectors recorded 1 significant deficiency.

What Should Koshkonong Residents Do?

1
Consider a filter certified for lead
Look for NSF/ANSI 53 certification for lead reduction.
2
Check for a lead service line
Lead reaches tap water mainly through service lines and household plumbing. Suppliers now publish an inventory identifying lead lines.
3
Flush before drinking
If water has sat in pipes more than six hours, run the cold tap for two minutes before drinking or cooking.

Nearby Cities in Wisconsin

Watertown, Wi Tap Water Quality 2026 Jefferson Fort Atkinson, Wi Tap Water Quality 2026 Jefferson Jefferson, Wi Tap Water Quality 2026 Jefferson Lake Mills, Wi Tap Water Quality 2026 Jefferson Waterloo, Wi Tap Water Quality 2026 Jefferson Johnson Creek, Wi Tap Water Quality 2026 Jefferson