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Community Water System · PWS WI2684642

Delafield Waterworks

Operator location Delafield, Wisconsin - 42% of 36 violations are health-based (upper-third health share (> 23%)); groundwater source; 300 served per SDWIS.

300
People served (this PWS)
36
EPA violations (this PWS)
15
Health-based (this PWS)
Untested
UCMR5 (this PWS)
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Delafield Waterworks standing, mid SDWIS violation third

42% of 36 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 42% is upper-third health share (> 23%).

The verdict

Delafield Waterworks lands in the middle third by violation volume (36), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is smaller (300; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 42% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.

36
Total EPA violations on record
42%
Health-based (MCL / treatment failure)
300
People served by this PWS (SDWIS)
N/A
PFAS compounds detected (UCMR5)

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
111
County
Waukesha
School/Daycare
No
MCL Violations
15
Monitoring Violations
19
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Combined Radium (-226 and -228) MCL 11 2001
Gross Alpha, Excl. Radon and U MR 6 2000
Combined Radium (-226 and -228) MR 6 2000
Gross Alpha, Excl. Radon and U MCL 4 2001
Radium-226 MR 3 2000
Radium-228 MR 3 2000
Consumer Confidence Rule Other 2 2001
Lead and Copper Rule MR 1 1995

Violation Count vs. the National Corpus

Delafield Waterworks has 36 recorded EPA violations, 47% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 52% carry more. 42% of this system's own violations are health-based (15 of 36), and it ranks unranked by population served among that same cohort.

EPA violations vs. the national water-system corpus

Public water systems serving 500+ people (EPA SDWIS)

36 Lower than most fewer violations than 52% 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

Health-based violations on Delafield Waterworks

15 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for WI2684642.

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

Nationwide peers

36 violations · 300 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

What to do with Delafield 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