Non-Transient Non-Community Water System · PWS WA5310811
Maxwelton Water System
Operator location Coupeville, Washington - 29% of 38 violations are health-based (upper-third health share (> 23%)); groundwater source; 1,700 served per SDWIS.
- 1,700
- People served (this PWS)
- 38
- EPA violations (this PWS)
- 11
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Maxwelton Water System standing, mid SDWIS violation third
29% of 38 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 29% is upper-third health share (> 23%). Population rank #14,938 of 29,740 among systems serving 500+.
The verdict
Maxwelton Water System lands in the middle third by violation volume (38), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is mid-pack at 1,700 (mid served population (≤ 3,309)). Health-based share is 29% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- #14,938 of 29,740
- Population · /systems
- #395 of 766
- Population · WA
- 38
- Total EPA violations on record
- 29%
- 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
- Non-Transient Non-Community
- Owner Type
- Private
- Connections
- 5
- County
- Island
- School/Daycare
- Yes
- MCL Violations
- 11
- Monitoring Violations
- 26
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Lead and Copper Rule | MR | 15 | 2011 |
| Coliform (TCR) | MCL | 11 | 2004 |
| TTHM | MR | 4 | 2024 |
| Total Haloacetic Acids (HAA5) | MR | 4 | 2024 |
| Coliform (TCR) | MR | 2 | 1994 |
| Nitrate | MR | 1 | 2024 |
Violation Count vs. the National Corpus
Maxwelton Water System has 38 recorded EPA violations, 49% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 50% carry more. 29% of this system's own violations are health-based (11 of 38), and it ranks #14,938 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)
38 Lower than most fewer violations than 50% 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 Maxwelton Water System
11 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for WA5310811.
Sources: EPA SDWIS · Washington State Department of Health, Office of Drinking Water
Nationwide peers
38 violations · 1,700 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.
Cross-state systems near this population served
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Maxwelton Water System
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.