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Community Water System · PWS WA5397500

Winlock City Of

Operator location Winlock, Washington - larger served population (> 3,309) at 3,502 people served; 237 SDWIS violations on record from groundwater sources.

3,502
People served (this PWS)
237
EPA violations (this PWS)
7
Health-based (this PWS)
Untested
UCMR5 (this PWS)
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Winlock City Of standing, high SDWIS violation third

3,502 people served (SDWIS) - larger served population (> 3,309). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 3% is middle-third health share (≤ 23%). Population rank #9,604 of 29,740 among systems serving 500+.

The verdict

Winlock City Of sits in the upper third of the sitemap cohort by violation count (237), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is large (3,502; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 3% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.

#9,604 of 29,740
Population · /systems
#239 of 766
Population · WA
237
Total EPA violations on record
3%
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
1,040
County
Lewis
School/Daycare
No
MCL Violations
7
Monitoring Violations
223
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Nitrate MR 12 2007
cis-1,2-Dichloroethylene MR 8 2008
Vinyl chloride MR 8 2008
1,1-Dichloroethylene MR 8 2008
trans-1,2-Dichloroethylene MR 8 2008
1,1,1-Trichloroethane MR 8 2008
Carbon tetrachloride MR 8 2008
1,2-Dichloropropane MR 8 2008
CHLOROBENZENE MR 8 2008
Benzene MR 8 2008
Toluene MR 8 2008
Styrene MR 8 2008
1,2,4-Trichlorobenzene MR 8 2008
DICHLOROMETHANE MR 8 2008
o-Dichlorobenzene MR 8 2008
1,1,2-Trichloroethane MR 8 2008
Tetrachloroethylene MR 8 2008
Ethylbenzene MR 8 2008
p-Dichlorobenzene MR 8 2008
Trichloroethylene MR 8 2008
1,2-Dichloroethane MR 8 2008
Coliform (TCR) MCL 7 1998
Consumer Confidence Rule Other 4 2014
Coliform (TCR) MR 2 2010
Pentachlorophenol MR 2 2008
Arsenic MR 2 2005
Selenium MR 2 2005
Diquat MR 2 2006
Cadmium MR 2 2005
Barium MR 2 2005

Violation Count vs. the National Corpus

Winlock City Of has 237 recorded EPA violations, 88% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 12% carry more. 3% of this system's own violations are health-based (7 of 237), and it ranks #9,604 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)

237 Higher than most more violations than 88% 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 Winlock City Of

EPA SDWIS lists 3,502 people served and 1,040 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.

Sources: EPA SDWIS · Washington State Department of Health, Office of Drinking Water

Nationwide peers

237 violations · 3,502 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

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 Winlock City Of

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

  • See how every tracked system in Washington compares on the same EPA violation measures. Washington 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