Marion County, OR flood risk explained
Flood hazard in Marion County sits at the 90.5th national percentile, a middling flood hazard by national standards; driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about once every 1 years. That's a county-wide figure, not a per-address one — FEMA's parcel maps are a live lookup, not a bulk file.
Who actually carries the flood insurance FEMA requires
29.5% of the homes FEMA requires to carry flood insurance in Marion County — those inside the mapped Special Flood Hazard Area — actually have a policy in force: 786 policies against 2,669 mandated structures, which means a meaningful share of legally-required coverage simply isn't there. Looking beyond the mandated zone, 1.3% of all residential structures in Marion County carry flood coverage voluntarily or otherwise — relevant because most NFIP claims nationally come from outside the mapped SFHA.
How Marion County compares nationally
Among the 3144 US counties FEMA scores for flood hazard, Marion County ranks 317 — 1 being the highest hazard nationally — and 214 by population among all 3144 counties covered here, where 1 is the largest. Marion County, Oregon is home to about 352,867 people across 1,180.84 square miles of land.
Checking a specific address in Marion County
FEMA counts 91,193 residential structures in Marion County overall, 1,169 of them carrying some form of NFIP coverage — but a lender or insurer cares about one parcel, not that county total.
Where Marion County's figures come from
Every figure on this page traces to a named FEMA dataset, documented in the methodology guide. If you're unsure why any of this insurance requirement exists at all, the SFHA explainer covers it from first principles.