Washington vs Oregon
Statewide drinking water quality comparison — violation rates, PFAS prevalence, and system-level risk
Quick Answer
Washington has a lower open-violation rate (0.0% vs. 0.7%). Washington has 195 utilities with PFAS records (34.3%) vs. 106 in Oregon (38.3%).
WA · 569 utilities
0.0%
Open violation rate
34.3%
PFAS detection rate
0
High/critical risk
100.0%
Safe/low risk
OR · 277 utilities
0.7%
Open violation rate
38.3%
PFAS detection rate
0
High/critical risk
100.0%
Safe/low risk
Head-to-Head Comparison
| Metric | Washington | Oregon |
|---|---|---|
| Total Utilities | 569 | 277 |
| Population Served | 9,197,069 | 3,658,175 |
| Well Water % | 22% on private wells | 32% on private wells |
| Open Violation Rate | 0.0%(0 utilities) | 0.7%(2 utilities) |
| PFAS Detection Rate | 34.3%(195 utilities) | 38.3%(106 utilities) |
| High/Critical Risk Utilities | 0 | 0 |
| Safe/Low Risk Rate | 100.0%(569 utilities) | 100.0%(277 utilities) |
| Top Contaminants |
State Profiles
Washington
Washington has 569 community water systems serving approximately 9.2 million residents. Primary water sources include groundwater. The most commonly reported contaminants include disinfection byproducts, lead. 22% of Washington residents rely on private wells. DOH holds primary enforcement authority under the Safe Drinking Water Act.
Oregon
Oregon has 277 community water systems serving approximately 3.7 million residents. Primary water sources include surface water. The most commonly reported contaminants include disinfection byproducts, lead. 32% of Oregon residents rely on private wells. OHA holds primary enforcement authority under the Safe Drinking Water Act.
Highest-Risk Systems
Key Differences
Open violation rate: Washington at 0.0% vs. Oregon at 0.7%. Washington has a lower rate of systems with unresolved health-based violations.
PFAS detection: Washington has PFAS records at 34.3% of utilities vs. 38.3% in Oregon. Rates reflect UCMR 5 monitoring (2023–2025).
Well water reliance: Washington (22% on private wells) vs. Oregon (32% on private wells). Private well users are not regulated under the Safe Drinking Water Act and should test independently.