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Non-Transient Non-Community Water System · PWS WA5300620

Port of Shelton Johns Prairie

Operator location Shelton, Washington - 24% of 25 violations are health-based (upper-third health share (> 23%)); groundwater source; 328 served per SDWIS.

328
People served (this PWS)
25
EPA violations (this PWS)
6
Health-based (this PWS)
Untested
UCMR5 (this PWS)
Follow published updates (RSS)

Port of Shelton Johns Prairie standing, mid SDWIS violation third

24% of 25 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 24% is upper-third health share (> 23%).

The verdict

Port of Shelton Johns Prairie lands in the middle third by violation volume (25), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is smaller (328; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 24% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.

25
Total EPA violations on record
24%
Health-based (MCL / treatment failure)
328
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
Non-Transient Non-Community
Owner Type
Local
Connections
14
County
Mason
School/Daycare
No
MCL Violations
6
Monitoring Violations
15
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MCL 6 2000
Coliform (TCR) MR 5 1996
Lead and Copper Rule MR 1 1998
Selenium MR 1 1979
Gross Alpha, Excl. Radon and U MR 1 1979
Barium MR 1 1979
Chromium MR 1 1979
Nitrate MR 1 1979
Fluoride MR 1 1979
Arsenic MR 1 1979
Cadmium MR 1 1979
Mercury MR 1 1979

Violation Count vs. the National Corpus

Port of Shelton Johns Prairie has 25 recorded EPA violations, 37% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 62% carry more. 24% of this system's own violations are health-based (6 of 25), 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)

25 Lower than most fewer violations than 62% 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 Port of Shelton Johns Prairie

6 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for WA5300620.

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

Nationwide peers

25 violations · 328 served: nearest cross-state SDWIS matches.

What to do with Port of Shelton Johns Prairie

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