Photo: M.O. Stevens · CC BY 3.0On FEMA’s figures, Wilsonville faces about as much hazard damage per building as the typical U.S. town, mostly from earthquakes
On FEMA’s National Risk Index, Wilsonville gets a C+ for hazard risk: higher expected damage per building than 57% of U.S. towns, #38 of 142 in Oregon. Most of that expected damage is earthquakes (54%), then river and rain flooding (44%). Flood insurance has paid 3 claims here since 1996.
Graded on FEMA’s expected yearly building damage per dollar of building value (NRI v1.20, December 2025), weighted by where residents live; flood claims are shown, not graded. How hazard risk is graded
What Wilsonville faces
Each hazard’s share of the building damage FEMA expects here, and how its rate compares with the rest of the country.
Earthquakes
River and rain flooding
Shares are of FEMA’s expected building damage, the measure the grade uses; ranks compare each hazard’s building-damage rate with all 85,154 U.S. census tracts. In FEMA’s terms, river and rain flooding is FEMA’s “Inland Flooding” (rivers and streams overflowing their banks, or rain overwhelming drainage). FEMA defines coastal flooding as high or rising tides and storm surge, so surge damage is counted there. Drought isn’t listed: FEMA counts its losses in crops only.
What’s behind Wilsonville’s grade
Earthquakes are 54% of the building damage FEMA expects in Wilsonville, and Wilsonville’s rate of earthquakes damage is higher than 88% of U.S. census tracts. Next is river and rain flooding at 44% (lower than 71% of U.S. census tracts).
C+ #38 of 142 in Oregon; higher expected damage per building than 57% of U.S. towns (21,298).
Wilsonville’s residents live in 7 census tracts; FEMA’s figures are combined by where they live.
The typical Oregon town has higher expected damage than 69% of U.S. towns; within the state, Wilsonville has less expected damage per building than 74% of Oregon towns.
In dollars, FEMA expects about $13.1M a year in losses across Wilsonville: $9.3M to buildings, the rest to people and crops.
Does Wilsonville flood? Rarely: 3 flood claims since 1996
Every paid claim on a federal flood insurance policy in Wilsonville, from FEMA’s records: 0.3 per 1,000 homes, fewer than 96% of the 13,809 U.S. towns with a flood insurance record.
Wilsonville isn’t in FEMA’s Community Rating System, which cuts flood insurance up to 45% in towns that do extra flood-proofing.
Insurance rates: Clackamas County.2 federal disasters brought FEMA money to Wilsonville
Disasters that paid out in Wilsonville itself (aid to households or repair grants to the City of Wilsonville), newest first, with that year’s flood claims.
- 2021Severe Winter Storm$366K to the City of Wilsonville for repairs
- 2020Wildfires and Straight-line Winds42 households applied for aid$6K aid approved
Clackamas County has had 15 natural disasters declared by the President since 1953, most often severe storms, then floods. Not counted: the 2005 Hurricane Katrina evacuee emergency, which covered counties that took in evacuees.
Also 5 FEMA wildfire suppression grants (Fire Management Assistance, not a disaster declaration) for fires in Clackamas County, 2014–2022.
Old photos of Wilsonville after a storm or flood belong in the town’s history. Add one, or share what you remember below.
Add to the Wilsonville archive →Get ready for what Wilsonville faces
A short kit for the hazards that drive the building damage here, what to check before you buy, and where neighbors get alerts.
- Drop, cover and hold on.
- Strap tall furniture and the water heater to the wall.
- Know how to shut off the gas.
- Turn around at flooded roads: a foot of moving water can carry off a car.
- Flood insurance usually takes 30 days to start, so buy it before the forecast.
- Keep papers and medicines up high, in a grab-and-go bag.
- Look up the address on FEMA’s flood map.
- Ask the seller or landlord whether it has ever flooded, and what flood insurance costs there.
- Get a flood insurance quote early: policies usually start 30 days after you buy.
Know where neighbors sign up for alerts? Add it to the Handbook so everyone has it.
Questions about natural hazards in Wilsonville
Is Wilsonville at risk for natural disasters?
On FEMA’s National Risk Index, Wilsonville has higher expected damage per building than 57% of U.S. towns: C+ for hazard risk, #38 of 142 in Oregon. Most of the expected damage is earthquakes (54%) and river and rain flooding (44%). This is FEMA’s model of an average year for today’s buildings, not a forecast.
Does Wilsonville flood?
Flood insurance has paid 3 claims in Wilsonville since 1996, $74K in all, or 0.3 per 1,000 homes, fewer than 96% of U.S. towns with a flood insurance record.
Is Wilsonville in a flood zone?
Flood zones are drawn street by street, so the answer depends on the address: look it up on FEMA’s flood map. In Clackamas County, 41% of homes in mapped flood zones carry federal flood insurance, and 0.9% of all homes do.
How much is flood insurance in Wilsonville?
FEMA’s Community Rating System list shows no discount for Wilsonville’s flood program. Premiums depend on the building; policies usually start 30 days after you buy, so get a quote early.
What was the biggest storm in Wilsonville?
By FEMA money that reached Wilsonville, Severe Winter Storm (2021): $366K to the City of Wilsonville for repairs.
Is Wilsonville at risk from earthquakes?
It is the largest share of the building damage FEMA expects here (54%), and Wilsonville’s rate for it is higher than 88% of U.S. census tracts.
Storm stories
Memories, warnings and help from neighbors in Wilsonville.
Sources: FEMA National Risk Index v1.20 (December 2025), census-tract table, combined by where Wilsonville’s residents lived in the 2020 census; OpenFEMA: NFIP redacted claims, multiple-loss properties, community status book and residential penetration rates, housing assistance (owners and renters), public assistance funded projects, hazard mitigation properties and disaster declarations. Homes: Census ACS 2020–24. Preparedness tips: Ready.gov. FEMA’s model is an average of expected damage, not a forecast. How hazard risk is graded.