Community Water System · PWS WA5392500
Walla Walla Water Division
Operator location Walla Walla, Washington - 59% of 141 violations are health-based (upper-third health share (> 23%)); surface water source; 42,959 served per SDWIS.
- 42,959
- People served (this PWS) Larger third of systems
- 141
- EPA violations (this PWS) Upper third of systems
- 83
- Health-based (this PWS) Upper third by health-based share
- No PFAS
- UCMR5 (this PWS) Tested, none detected
Walla Walla Water Division standing, high SDWIS violation third
59% of 141 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 59% is upper-third health share (> 23%). UCMR5: UCMR5 tested, none detected. Population rank #1,292 of 29,740 among systems serving 500+.
The verdict
Walla Walla Water Division sits in the upper third of the sitemap cohort by violation count (141), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is large (42,959; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 59% - most of this ledger is MCL or treatment-technique exceedance. UCMR5 tested this system and reported no PFAS above the minimum reporting level.
- #1,292 of 29,740
- Population · /systems
- #43 of 766
- Population · WA
- 141
- Total EPA violations on record
- 59%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
Based on EPA SDWIS violation history and UCMR5 PFAS testing only, not water taste, odor, infrastructure age, or contaminants outside the federally tracked set.
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 15,281
- County
- Walla Walla
- School/Daycare
- No
- MCL Violations
- 2
- Monitoring Violations
- 58
- Treatment Tech Violations
- 81
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Surface Water Treatment Rule | TT | 57 | 2017 |
| Long Term 2 Enhanced Surface Water Treatment Rule | TT | 24 | 2018 |
| Diquat | MR | 5 | 2005 |
| Coliform (TCR) | MR | 4 | 1992 |
| Lead and Copper Rule | MR | 4 | 1995 |
| Picloram | MR | 3 | 2022 |
| Dinoseb | MR | 3 | 2022 |
| 2,4,5-TP | MR | 3 | 2022 |
| Pentachlorophenol | MR | 3 | 2022 |
| Dalapon | MR | 3 | 2022 |
| Cadmium | MR | 2 | 2011 |
| Chromium | MR | 2 | 2011 |
| Mercury | MR | 2 | 2011 |
| Nitrate | MR | 2 | 2023 |
| Coliform (TCR) | MCL | 2 | 1996 |
| Barium | MR | 2 | 2011 |
| Fluoride | MR | 2 | 2011 |
| Arsenic | MR | 2 | 2011 |
| Selenium | MR | 2 | 2011 |
| CYANIDE | MR | 1 | 2011 |
| Nitrite | MR | 1 | 2011 |
| Antimony, Total | MR | 1 | 2011 |
| Beryllium, Total | MR | 1 | 2011 |
| TTHM | MR | 1 | 2021 |
| Aldicarb sulfoxide | MR | 1 | 2008 |
| OXAMYL | MR | 1 | 2008 |
| Aldicarb sulfone | MR | 1 | 2008 |
| Carbofuran | MR | 1 | 2008 |
| Aldicarb | MR | 1 | 2008 |
| Nickel | MR | 1 | 2011 |
Violation Count vs. the National Corpus
Walla Walla Water Division has 141 recorded EPA violations, 80% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 20% carry more. 59% of this system's own violations are health-based (83 of 141), and it ranks #1,292 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)
141 Higher than most more violations than 80% 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
How many violations vs. how serious, among peer systems
Walla Walla Water Division plotted against 29 peer public water systems (500+ people served), by total violation count (x) and the share of those violations that are health-based (y). The crosshair sits at this sample's own median on each axis. A high violation count does not automatically mean a serious record: most monitoring and reporting violations are minor, not health-based.
Violation volume vs. health-based share
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 116 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| PFBS | 7/25/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 7/25/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxS | 7/25/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTA | 7/25/2024 | <8.00 ppt | 8.00 ppt | Not Detected |
| 8:2 FTS | 7/25/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTrDA | 7/25/2024 | <7.00 ppt | 7.00 ppt | Not Detected |
| PFNA | 7/25/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| NMeFOSAA | 7/25/2024 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFHpS | 7/25/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 7/25/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| NFDHA | 7/25/2024 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFEESA | 7/25/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMBA | 7/25/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| NEtFOSAA | 7/25/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFMPA | 7/25/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOS | 7/25/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| 4:2 FTS | 7/25/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 7/25/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBA | 7/25/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| HFPO-DA | 7/25/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| ADONA | 7/25/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| 9Cl-PF3ONS | 7/25/2024 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 7/25/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFUnA | 7/25/2024 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFHxA | 7/25/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| 6:2 FTS | 7/25/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFPeA | 7/25/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 7/25/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOA | 7/25/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFMBA | 4/16/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxS | 4/16/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBS | 4/16/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| 8:2 FTS | 4/16/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHpA | 4/16/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| NMeFOSAA | 4/16/2024 | <6.00 ppt | 6.00 ppt | Not Detected |
| NEtFOSAA | 4/16/2024 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTrDA | 4/16/2024 | <7.00 ppt | 7.00 ppt | Not Detected |
| PFTA | 4/16/2024 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFHpS | 4/16/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 4/16/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| NFDHA | 4/16/2024 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFMPA | 4/16/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFPeA | 4/16/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFNA | 4/16/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHxA | 4/16/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOS | 4/16/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOA | 4/16/2024 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFEESA | 4/16/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 4/16/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
| 4:2 FTS | 4/16/2024 | <3.00 ppt | 3.00 ppt | Not Detected |
Health-based violations on Walla Walla Water Division
83 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for WA5392500.
Sources: EPA SDWIS · Washington State Department of Health, Office of Drinking Water
Nationwide peers
141 violations · 42,959 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 with similar served population
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Walla Walla Water Division
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.
Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.