High Risk Oregon  ·  Earthquake / Flooding

Multnomah County OR

EMERGENCY PREPAREDNESS & DISASTER RISK PROFILE  ·  LAST UPDATED: Mar 2026

7/ 10
Threat Score
Population
815,428
Area
465
sq miles
Primary Hazard
Earthquake / Flooding
FEMA Disasters
40
federally declared

Multnomah County and Portland face serious Cascadia Subduction Zone earthquake risk. A full rupture of the Cascadia fault could produce a magnitude 9.0 earthquake and tsunami affecting the entire Pacific Northwest coast. Portland's older building stock — much of it unreinforced masonry — is particularly vulnerable. The Columbia and Willamette Rivers create major flood risk, and the Columbia River Gorge creates wildfire corridors.

// Preparedness Recommendations

  • Evacuation routes inland should be identified in advance.
  • Store at least 72 hours of food and water.
  • Elevate critical belongings above flood level.
  • Have backup power ready in case of grid failure.

// Recommended Supplies

Essential gear for power outages, severe weather, and emergency situations in your area.

// Risk Intelligence

Threat Score 7 / 10    High Risk
Primary Hazard Earthquake / Flooding
Secondary Hazard Wildfire
FEMA Flood Zone Zone X (Seismic High Risk)
Federally Declared Disasters 40
Last Major Event Cascadia Earthquake Risk (ongoing)
Event Frequency Major event every 4–6 years

// Emergency Operations

Emergency Mgmt Phone (503) 988-6700
Emergency Shelters 44 designated facilities
Evacuation Routes I-5 South, I-84 East, US-26 West, OR-99E South

// County Profile

County Multnomah County OR
State Oregon (OR)
Population 815,428
Area 465 sq miles
FEMA Region Zone X (Seismic High Risk)

// Major Cities

Gresham OR Portland OR

// Cities in This County

// Other Oregon Counties

// Nearby Infrastructure Risks

Critical infrastructure facilities within or near this area that could affect civilian safety during emergencies, conflict, or infrastructure failures.

🚂
Columbia River Gorge Rail Hazmat Corridor OR WA
Rail Infrastructure  ·  Portland, OR  ·  BNSF Railway / Union Pacific  ·  5-mi risk zone
8/10 High
🌊
Bonneville Dam OR/WA
Major Dam  ·  Cascade Locks  ·  US Army Corps of Engineers  ·  75-mi risk zone
8/10 High
🏥
Oregon Health and Science University Portland OR
Major Hospital  ·  Portland, OR  ·  OHSU Health  ·  25-mi risk zone
8/10 High
🌊
Bonneville Dam OR WA
Major Dam  ·  Cascade Locks, OR  ·  US Army Corps of Engineers  ·  30-mi risk zone
8/10 High
💧
Portland Water Bureau OR
Water Treatment  ·  Portland, OR  ·  Portland Water Bureau  ·  5-mi risk zone
7/10 High
🏟
Portland International Airport OR
Stadium / Arena  ·  Portland, OR  ·  Port of Portland  ·  10-mi risk zone
7/10 High
Bonneville Dam Power Plant OR WA
Power Plant  ·  Cascade Locks, OR  ·  US Army Corps of Engineers / BPA  ·  10-mi risk zone
7/10 High
Port of Portland OR
Port / Marine Terminal  ·  Portland, OR  ·  Port of Portland  ·  10-mi risk zone
7/10 High
🌉
Columbia River Crossing Interstate Bridge OR WA
Bridge / Critical Crossing  ·  Portland, OR  ·  Oregon and Washington Departments of Transportation  ·  5-mi risk zone
7/10 High
💧
Portland Bureau of Environmental Services Bull Run Watershed OR
Water Treatment  ·  Portland, OR  ·  Portland Water Bureau  ·  25-mi risk zone
7/10 High
McCormick and Baxter Superfund OR
Superfund Site  ·  Portland, OR  ·  Various / EPA  ·  5-mi risk zone
7/10 High
🌊
Willamette River Levee System OR
Major Dam  ·  Portland, OR  ·  US Army Corps of Engineers  ·  10-mi risk zone
7/10 High
🏥
Legacy Emanuel Medical Center Portland OR
Major Hospital  ·  Portland, OR  ·  Legacy Health  ·  25-mi risk zone
7/10 High
🏟
Moda Center Portland OR
Stadium / Arena  ·  Portland, OR  ·  Portland Trail Blazers / NBA  ·  2-mi risk zone
7/10 High

Infrastructure risk data is for emergency preparedness awareness. Facility locations are publicly known. Always follow official emergency guidance.