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Community Water System · PWS WI6170267

Knapp Waterworks

Operator location Knapp, Wisconsin - smaller served population (≤ 999) at 486 people served; 82 SDWIS violations on record from groundwater sources.

486
People served (this PWS)
82
EPA violations (this PWS)
1
Health-based (this PWS)
Untested
UCMR5 (this PWS)
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Knapp Waterworks standing, high SDWIS violation third

486 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 1% is middle-third health share (≤ 23%).

The verdict

Knapp Waterworks sits in the upper third of the sitemap cohort by violation count (82), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (486; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 1% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.

82
Total EPA violations on record
1%
Health-based (MCL / treatment failure)
486
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
229
County
Dunn
School/Daycare
No
MCL Violations
0
Monitoring Violations
69
Treatment Tech Violations
1

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Chlorine MR 22 2018
Coliform (TCR) MR 17 2013
Revised Total Coliform Rule MON 12 2024
Lead and Copper Rule MR 6 2017
Consumer Confidence Rule Other 4 2010
E. COLI MR 4 2022
TTHM MR 4 2020
Total Haloacetic Acids (HAA5) MR 4 2020
Public Notice Other 2 2007
Stage 1 Disinfectants and Disinfection Byproducts Rule TT 1 2025

Violation Count vs. the National Corpus

Knapp Waterworks has 82 recorded EPA violations, 69% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 31% carry more. 1% of this system's own violations are health-based (1 of 82), 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)

82 Around the middle fewer violations than 31% 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

Population served record for Knapp Waterworks

EPA SDWIS lists 486 people served and 229 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.

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

Nationwide peers

82 violations · 486 served: nearest cross-state SDWIS matches.

Cross-state systems with comparable violation load

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

4 peers

What to do with Knapp 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