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Community Water System · PWS WI1280104

Jefferson Waterworks

Operator location Jefferson, Wisconsin - 85% of 61 violations are health-based (upper-third health share (> 23%)); groundwater source; 7,926 served per SDWIS.

7,926
People served (this PWS)
61
EPA violations (this PWS)
52
Health-based (this PWS)
No PFAS
UCMR5 (this PWS)
Follow published updates (RSS)

Jefferson Waterworks standing, mid SDWIS violation third

85% of 61 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 85% is upper-third health share (> 23%). UCMR5: UCMR5 tested, none detected. Population rank #5,649 of 29,740 among systems serving 500+.

The verdict

Jefferson Waterworks lands in the middle third by violation volume (61), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is large (7,926; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 85% - most of this ledger is MCL or treatment-technique exceedance. UCMR5 tested this system and reported no PFAS above the minimum reporting level.

#5,649 of 29,740
Population · /systems
#113 of 744
Population · WI
61
Total EPA violations on record
85%
Health-based (MCL / treatment failure)

Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.

System Details

System Type
Community
Owner Type
Local
Connections
3,072
County
Jefferson
School/Daycare
No
MCL Violations
51
Monitoring Violations
6
Treatment Tech Violations
1

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Combined Radium (-226 and -228) MCL 38 2024
Gross Alpha, Excl. Radon and U MCL 9 2010
Lead and Copper Rule MR 4 2024
Coliform (TCR) MCL 4 1993
Public Notice Other 1 2010
Lead and Copper Rule TT 1 1993
Coliform (TCR) MR 1 2000
Gross Alpha, Excl. Radon and U MR 1 2002

Violation Count vs. the National Corpus

Jefferson Waterworks has 61 recorded EPA violations, 62% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 38% carry more. 85% of this system's own violations are health-based (52 of 61), and it ranks #5,649 of 29,740 by population served among that same cohort.

EPA violations vs. the national water-system corpus

Public water systems serving 500+ people (EPA SDWIS)

61 Around the middle fewer violations than 38% of 29,740 water systems

the national water-system corpus, bucketed by value

Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source EPA SDWIS · 2026-05-15

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 174 samples detected PFAS.

Contaminant Date Result MRL Status
PFHpS 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFOS 9/23/2024 <4.00 ppt 4.00 ppt Not Detected
ADONA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFDA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeS 9/23/2024 <4.00 ppt 4.00 ppt Not Detected
PFBS 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFHpA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFTA 9/23/2024 <8.00 ppt 8.00 ppt Not Detected
PFTrDA 9/23/2024 <7.00 ppt 7.00 ppt Not Detected
NMeFOSAA 9/23/2024 <6.00 ppt 6.00 ppt Not Detected
HFPO-DA 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
PFBA 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
6:2 FTS 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
PFHxS 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFNA 9/23/2024 <4.00 ppt 4.00 ppt Not Detected
PFOA 9/23/2024 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
NFDHA 9/23/2024 <20.00 ppt 20.00 ppt Not Detected
NEtFOSAA 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
PFMBA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFMPA 9/23/2024 <4.00 ppt 4.00 ppt Not Detected
PFEESA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
4:2 FTS 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
9Cl-PF3ONS 9/23/2024 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
PFUnA 9/23/2024 <2.00 ppt 2.00 ppt Not Detected
PFHxA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFDoA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFTA 9/23/2024 <8.00 ppt 8.00 ppt Not Detected
11Cl-PF3OUdS 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
PFUnA 9/23/2024 <2.00 ppt 2.00 ppt Not Detected
PFHpS 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeS 9/23/2024 <4.00 ppt 4.00 ppt Not Detected
NFDHA 9/23/2024 <20.00 ppt 20.00 ppt Not Detected
PFEESA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFMBA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFHxS 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
PFDA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
4:2 FTS 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFTrDA 9/23/2024 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 9/23/2024 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 9/23/2024 <6.00 ppt 6.00 ppt Not Detected
PFHpA 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFOS 9/23/2024 <4.00 ppt 4.00 ppt Not Detected
PFBS 9/23/2024 <3.00 ppt 3.00 ppt Not Detected
PFNA 9/23/2024 <4.00 ppt 4.00 ppt Not Detected
PFMPA 9/23/2024 <4.00 ppt 4.00 ppt Not Detected

Health-based violations on Jefferson Waterworks

52 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for WI1280104.

Sources: EPA SDWIS · Wisconsin DNR, Drinking Water and Groundwater

Nationwide peers

61 violations · 7,926 served: nearest cross-state SDWIS matches.

Cross-state systems near this violation count

Nearest cross-state community systems (500+ served) by total SDWIS violations on record.

4 peers

Cross-state systems with similar served population

Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).

4 peers

What to do with Jefferson Waterworks

Use this system's EPA-reported record as a starting filter, not a final verdict.

  • See how every tracked system in Wisconsin compares on the same EPA violation measures. Wisconsin systems
  • Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
  • Find and compare another public water system by name or PWSID. Search systems

EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater