Marion County, OR
drinking water quality
352,867 residents · 197 public water systems · 26 ZIP codes
EPA sampled 11 of 197 public water systems here, together serving about 313,094 people. The highest reading was PFHxS at 3.9 ng/L at City of Keizer. Last sampled 9/7/2023.
What was found
| Compound | Highest result | Federal limit | Ratio |
|---|---|---|---|
| PFHxS | 3.9 ng/L | 10 ng/L | 0.4× |
Health-based violations
Separately from PFAS, EPA records 49 health-based violations across 34 of the county’s water systems since 2020, the most recent in 2026. They involved E. coli, contaminant 0200, lead and copper, total coliform, contaminant 0300, arsenic.
What this means
PFAS are industrial chemicals that EPA describes as breaking down only very slowly in the environment. In April 2024 EPA set the first enforceable national limits: 4 ng/L for PFOA and PFOS, 10 ng/L for PFHxS, PFNA and GenX.
These figures are county-level and come from EPA’s sampling of public water systems. They describe the worst result found in the county, not what comes out of any particular tap — that depends on which system serves the address, and on the plumbing in the building. A private well is not covered by this programme at all.
ZIP codes in Marion County
97002 · 97020 · 97026 · 97032 · 97071 · 97137 · 97301 · 97302 · 97303 · 97305 · 97306 · 97310 · 97317 · 97325 · 97342 · 97346 · 97352 · 97358 · 97362 · 97373 · 97375 · 97381 · 97383 · 97384 · 97385 · 97392
Readings are county-level, so every ZIP here shares the figure above. Search your ZIP on the map to see it in context.