Community Water System · PWS OR4100537
Monmouth, City Of
Operator location Monmouth, Oregon - larger served population (> 3,309) at 11,651 people served; 33 SDWIS violations on record from surface water sources.
- 11,651
- People served (this PWS)
- 33
- EPA violations (this PWS)
- 6
- Health-based (this PWS)
- No PFAS
- UCMR5 (this PWS)
Monmouth, City Of standing, mid SDWIS violation third
11,651 people served (SDWIS) - larger served population (> 3,309). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 18% is middle-third health share (≤ 23%). UCMR5: UCMR5 tested, none detected. Population rank #4,202 of 29,740 among systems serving 500+.
The verdict
Monmouth, City Of lands in the middle third by violation volume (33), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is large (11,651; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 18% (middle-third health share (≤ 23%)). UCMR5 tested this system and reported no PFAS above the minimum reporting level.
- #4,202 of 29,740
- Population · /systems
- #55 of 373
- Population · OR
- 33
- Total EPA violations on record
- 18%
- 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
- 3,027
- County
- Polk
- School/Daycare
- No
- MCL Violations
- 4
- Monitoring Violations
- 20
- Treatment Tech Violations
- 2
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Surface Water Treatment Rule | MR | 4 | 2021 |
| Groundwater Rule | MR | 3 | 2014 |
| Coliform (TCR) | MR | 2 | 1998 |
| Coliform (TCR) | MCL | 2 | 1998 |
| Nitrate | MR | 2 | 2008 |
| TTHM | MR | 2 | 2023 |
| Total Haloacetic Acids (HAA5) | MR | 2 | 2023 |
| Lead and Copper Rule | MR | 2 | 2021 |
| Surface Water Treatment Rule | TT | 2 | 2015 |
| Nitrate | MCL | 2 | 2000 |
| Revised Total Coliform Rule | MON | 1 | 2021 |
| Gross Alpha, Excl. Radon and U | MR | 1 | 1976 |
| Combined Radium (-226 and -228) | MR | 1 | 1976 |
Violation Count vs. the National Corpus
Monmouth, City Of has 33 recorded EPA violations, 45% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 54% carry more. 18% of this system's own violations are health-based (6 of 33), and it ranks #4,202 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)
33 Lower than most fewer violations than 54% 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
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 116 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| 11Cl-PF3OUdS | 7/27/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFUnA | 7/27/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFHxA | 7/27/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 7/27/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 7/27/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFNA | 7/27/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOS | 7/27/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| 9Cl-PF3ONS | 7/27/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFPeA | 7/27/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxS | 7/27/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 7/27/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBS | 7/27/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOA | 7/27/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| ADONA | 7/27/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| HFPO-DA | 7/27/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBA | 7/27/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| 6:2 FTS | 7/27/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| 4:2 FTS | 7/27/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMPA | 7/27/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFEESA | 7/27/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 7/27/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHpS | 7/27/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| NMeFOSAA | 7/27/2023 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFMBA | 7/27/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| NEtFOSAA | 7/27/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTrDA | 7/27/2023 | <7.00 ppt | 7.00 ppt | Not Detected |
| PFTA | 7/27/2023 | <8.00 ppt | 8.00 ppt | Not Detected |
| 8:2 FTS | 7/27/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| NFDHA | 7/27/2023 | <20.00 ppt | 20.00 ppt | Not Detected |
| 8:2 FTS | 4/11/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFUnA | 4/11/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 4/11/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| 9Cl-PF3ONS | 4/11/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| ADONA | 4/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| HFPO-DA | 4/11/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBA | 4/11/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHxA | 4/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| 4:2 FTS | 4/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeA | 4/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMPA | 4/11/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFMBA | 4/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| NFDHA | 4/11/2023 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFPeS | 4/11/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHpS | 4/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| 6:2 FTS | 4/11/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| NMeFOSAA | 4/11/2023 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFEESA | 4/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 4/11/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTA | 4/11/2023 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFTrDA | 4/11/2023 | <7.00 ppt | 7.00 ppt | Not Detected |
Population served record for Monmouth, City Of
EPA SDWIS lists 11,651 people served and 3,027 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS
Nationwide peers
33 violations · 11,651 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 with similar served population
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Monmouth, 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.