Community Water System · PWS OR4100252
Dayton, City Of
Operator location Dayton, Oregon - upper-third violation load (> 74 violations) with 103 EPA violations; groundwater source; 2,535 served (PWS-level, not municipal population).
- 2,535
- People served (this PWS)
- 103
- EPA violations (this PWS)
- 7
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Dayton, City Of standing, high SDWIS violation third
103 EPA SDWIS violations on record - upper-third violation load (> 74 violations). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 7% is middle-third health share (≤ 23%). Population rank #11,774 of 29,740 among systems serving 500+.
The verdict
Dayton, City Of sits in the upper third of the sitemap cohort by violation count (103), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is mid-pack at 2,535 (mid served population (≤ 3,309)). Health-based share is 7% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.
- #11,774 of 29,740
- Population · /systems
- #144 of 373
- Population · OR
- 103
- Total EPA violations on record
- 7%
- 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
- 904
- County
- Yamhill
- School/Daycare
- No
- MCL Violations
- 4
- Monitoring Violations
- 92
- Treatment Tech Violations
- 3
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 10 | 2010 |
| Nitrate | MR | 9 | 2009 |
| Coliform (TCR) | MCL | 4 | 2007 |
| Lead and Copper Rule | MR | 3 | 2005 |
| Groundwater Rule | TT | 3 | 2018 |
| Gross Alpha, Excl. Radon and U | MR | 2 | 1996 |
| E. COLI | MR | 2 | 2010 |
| Groundwater Rule | MR | 2 | 2020 |
| Arsenic | MR | 1 | 2002 |
| Cadmium | MR | 1 | 2002 |
| Chromium | MR | 1 | 2002 |
| CYANIDE | MR | 1 | 2002 |
| Beryllium, Total | MR | 1 | 2002 |
| Selenium | MR | 1 | 2002 |
| 1,2,4-Trichlorobenzene | MR | 1 | 2002 |
| Xylenes, Total | MR | 1 | 2002 |
| DICHLOROMETHANE | MR | 1 | 2002 |
| Vinyl chloride | MR | 1 | 2002 |
| trans-1,2-Dichloroethylene | MR | 1 | 2002 |
| 1,2-Dichloroethane | MR | 1 | 2002 |
| 1,2-Dichloropropane | MR | 1 | 2002 |
| Benzene | MR | 1 | 2002 |
| Toluene | MR | 1 | 2002 |
| Ethylbenzene | MR | 1 | 2002 |
| Styrene | MR | 1 | 2002 |
| Endrin | MR | 1 | 2002 |
| Methoxychlor | MR | 1 | 2002 |
| Toxaphene | MR | 1 | 2002 |
| Dalapon | MR | 1 | 2002 |
| Diquat | MR | 1 | 2002 |
Violation Count vs. the National Corpus
Dayton, City Of has 103 recorded EPA violations, 74% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 26% carry more. 7% of this system's own violations are health-based (7 of 103), and it ranks #11,774 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)
103 Around the middle fewer violations than 26% 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
SDWIS compliance record for Dayton, City Of
103 violations on record for OR4100252; use EPA SDWIS to confirm return-to-compliance dates and monitoring categories.
Sources: EPA SDWIS
Nationwide peers
103 violations · 2,535 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.
Cross-state systems near this population served
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Dayton, City Of
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Oregon compares on the same EPA violation measures. Oregon 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.