If you live on the Oregon coast, you have roughly 15 minutes.
That’s the estimated window between a major Cascadia Subduction Zone earthquake and the arrival of the first tsunami wave on the northern Oregon coast. Fifteen minutes is enough time — if you already know exactly where you’re going and you leave the moment the shaking stops.
It is not enough time to look up a map, pack a bag, wait for an official alert, or drive.
This guide covers what coastal Oregon residents — and anyone spending time on the coast — need to know about tsunami evacuation routes, zones, and planning.
The Cascadia Threat Is Real and Overdue
The Cascadia Subduction Zone runs roughly 700 miles off the Pacific Northwest coast, from northern California to British Columbia. Geologists estimate a full-margin rupture — a magnitude 8.0 to 9.2 earthquake — occurs on an average cycle of 200–500 years. The last full rupture was January 26, 1700. That was 325 years ago.
A full CSZ event would generate tsunamis affecting the entire Oregon coast within minutes. Communities like Seaside, Cannon Beach, Lincoln City, and Newport sit in low-lying coastal zones that would be inundated. State emergency managers model the Seaside area as one of the highest-risk communities on the coast due to population density and limited high ground.
This is not a reason to panic. It is a reason to prepare.
Find Your Evacuation Zone
Oregon has mapped tsunami inundation zones for the entire coast. These maps show which areas are likely to be flooded in a major event. If you live or work in one of these zones, you need an evacuation plan.
To find your zone:
- Visit the Oregon Office of Emergency Management tsunami hazard maps at oregon.gov/OEM
- For Clatsop County (Seaside, Cannon Beach, Astoria area): Clatsop County Emergency Management maintains updated inundation maps and posted route signage throughout the community
- Look for blue-and-white TSUNAMI HAZARD ZONE signs posted on roads — these mark where the hazard zone begins
- The companion TSUNAMI EVACUATION ROUTE signs (with an arrow and a person running uphill) mark your path out
If you’re not sure whether your home or workplace is in a hazard zone, assume it is and plan accordingly. The consequence of over-preparing is a walk you didn’t need. The consequence of under-preparing is worse.
The 15-Minute Rule: Why You Walk, Not Drive
After a major CSZ earthquake, roads in coastal areas will be damaged. Bridges may be impassable. Everyone in the hazard zone will be trying to leave at the same time. Traffic will be gridlocked within minutes.
Emergency managers and FEMA both recommend walking your tsunami evacuation route, not driving — for exactly this reason. Your evacuation plan should assume your car is unavailable or blocked.
What this means practically:
- You need to know a walking route to high ground from your home
- You need to know a walking route from your workplace
- If you have children in school, know the school’s evacuation plan
- If family members commute to different locations, each person needs their own route
Natural Warning Signs: Don’t Wait for a Siren
Official warning systems — sirens, Wireless Emergency Alerts, NOAA Weather Radio — may not activate in time for a locally-generated tsunami. The earthquake itself is your warning.
If you are on the coast and experience any of the following, move to high ground immediately without waiting for an official alert:
- Strong or prolonged earthquake shaking (especially 20+ seconds)
- The ocean suddenly receding — exposing beach or seafloor that is normally underwater
- A loud roaring sound from the ocean
Do not wait. Do not return to collect belongings. Do not go to the beach to watch.
Walk Your Route Before You Need It
Knowing where the route is on a map is not the same as being able to walk it under stress, in the dark, or with children and pets. Walk your actual evacuation route at least once — ideally twice a year.
When you walk it, note:
- How long it takes at a normal pace — then estimate the same walk while shaken and carrying a bag
- Any obstacles: fences, locked gates, narrow paths, steep sections that would slow down elderly family members
- Alternate routes in case your primary path is blocked by debris or fire
- Where the nearest vertical evacuation structure is, if your community has one
Vertical Evacuation: An Option in Some Communities
Some Oregon coastal communities have built or designated vertical evacuation structures — reinforced buildings tall enough to survive a tsunami wave where horizontal evacuation to high ground isn’t possible in time. Seaside has explored vertical evacuation planning; check with Clatsop County Emergency Management for current designated structures in your area.
Vertical evacuation is a backup option, not a substitute for knowing your walking route. Structures may be occupied, blocked, or damaged. High ground is always the primary goal.
Build a Household Evacuation Plan
A complete household tsunami evacuation plan answers these questions in advance:
- What is our primary walking route from home to high ground? How long does it take?
- What is our alternate route?
- Where do we reunite if we’re separated when it happens? (Pick a specific landmark on high ground)
- What does each person grab on the way out? (A pre-packed go-bag at the door means no decisions under stress)
- What is our plan for pets?
- Who checks on elderly neighbors?
- What is the kids’ school plan, and where do we meet them?
Write these answers down. Share them with everyone in your household. Practice the walk together.
Resources for Coastal Oregon Residents
- Oregon Office of Emergency Management: tsunami hazard maps, county contacts, preparedness guides — oregon.gov/OEM
- Clatsop County Emergency Management: local evacuation routes, community drills, vertical evacuation planning for the Seaside/Cannon Beach area
- Oregon Department of Geology and Mineral Industries (DOGAMI): detailed inundation modeling and hazard maps — oregongeology.org
- Great Oregon ShakeOut: annual statewide earthquake and tsunami drill — shakeout.org/oregon
- Ready.gov: federal tsunami preparedness guidance
The Oregon coast is one of the most beautiful places in the country to live and visit. Knowing your evacuation route doesn’t diminish that — it means you can enjoy it with the confidence that you’ve done your part.
If you haven’t walked your route yet, this week is a good time to start.