Community Water System · PWS WI6630252
Coon Valley Waterworks
Operator location Coon Valley, Wisconsin - 47% of 17 violations are health-based (upper-third health share (> 23%)); groundwater source; 765 served per SDWIS.
- 765
- People served (this PWS)
- 17
- EPA violations (this PWS)
- 8
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Coon Valley Waterworks standing, low SDWIS violation third
47% of 17 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 47% is upper-third health share (> 23%). Population rank #23,136 of 29,740 among systems serving 500+.
The verdict
Coon Valley Waterworks is in the lower third by violation count (17; lower-third violation load (≤ 21 violations)). A low count does not mean the system is unmonitored - monitoring and reporting violations still appear in SDWIS. Population served is smaller (765; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 47% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- #23,136 of 29,740
- Population · /systems
- #503 of 744
- Population · WI
- 17
- Total EPA violations on record
- 47%
- 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
- 340
- County
- Vernon
- School/Daycare
- No
- MCL Violations
- 7
- Monitoring Violations
- 3
- Treatment Tech Violations
- 1
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MCL | 7 | 1996 |
| Lead and Copper Rule | MR | 3 | 1993 |
| Public Notice | Other | 1 | 2024 |
| LEAD AND COPPER RULE REVISIONS | TT | 1 | 2024 |
| Consumer Confidence Rule | Other | 1 | 2000 |
Violation Count vs. the National Corpus
Coon Valley Waterworks has 17 recorded EPA violations, 28% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 71% carry more. 47% of this system's own violations are health-based (8 of 17), and it ranks #23,136 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)
17 Lower than most fewer violations than 71% 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 Coon Valley Waterworks
8 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for WI6630252.
Sources: EPA SDWIS · Wisconsin DNR, Drinking Water and Groundwater
Nationwide peers
17 violations · 765 served: nearest cross-state SDWIS matches.
Cross-state systems with similarly light violation ledgers
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
Cross-state systems with smaller service footprints
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Coon Valley 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.