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Tsunami Maps Provided By:
Important Map Notes
These maps show predictions for the estimated maximum extent of inundation for a LOCAL Cascadia tsunami (YELLOW) for all of Oregon and Washington overlaid on Google Maps. For portions of the Oregon coast only (e.g. currently Bandon to OR/CA border and Cannon Beach), these maps show TWO inundation lines: the estimated maximum extent of inundation for a LOCAL Cascadia tsunami (YELLOW) and a DISTANT tsunami (ORANGE). The entire Pacific coast including Puget Sound, are vulnerable to DISTANT tsunamis even if not depicted on this map. Sections of the coast marked by diagonal lines are currently unmapped, but are also vulnerable to tsunamis - Be vigilant and know what to do when at the coast.
Printable tsunami evacuation maps for Oregon coastal communities:
The technical lead agencies responsible for the development of these map products include the Oregon Department of Geology and Mineral Industries and Oregon Emergency Management.
Printable tsunami evacuation maps for Washington coastal communities:
The technical lead agencies responsible for the development of these map products include the Washington Department of Natural Resources and Washington Emergency Management.
Signs a Tsunami is coming …
Strong ground shaking, a loud roar from the ocean, the water receding from the shore unusually far and exposing the sea floor, or the water level rising rapidly are all nature’s warning signs that a tsunami may be coming. If you observe any of these signs, immediately move to higher ground or inland. A tsunami may arrive within minutes.
DO NOT WAIT for an official warning. The earthquake or changes in the water at the shore may be your only warning, and you may have only minutes to get to high ground. Stay away from low areas until told by officials that the danger has passed. Waves may impact the coast at irregular intervals for ten hours or longer.
For DISTANT tsunamis you may learn that a tsunami alert has been issued by the West Coast and Alaska Tsunami Warning Center through TV and radio station broadcasts, NOAA Weather Radio, or in some cases by announcements from emergency officials, aircraft, outdoor sirens, or mobile devices. Immediately, move away from beaches, harbors, or low-lying areas and follow instructions from emergency personnel. For LOCAL tsunamis there will not be time for an official warning; the earthquake is your warning. Both natural warnings and official alerts are equally important. Respond to whatever you hear or observe first!
The Oregon Department of Geology and Mineral Industries, in partnership with NOAA, is presently updating original (1st generation) tsunami evacuation maps of the entire Oregon coast with newer (2nd generation) maps that will be completed by late 2013. The 1st generation evacuation maps were made between 1995 and 2006 based on the maximum inundation expected for a LOCAL Cascadia tsunami. The interactive maps shown here are the 1st generation maps (a single yellow zone) for most areas on the coast. The 2nd generation maps are being created using information and new technology gained since the 2004 Indian Ocean tsunami, and include the maximum extent of inundation for both a DISTANT (ORANGE) tsunami and a LOCAL (YELLOW) Cascadia tsunami. These new maps will be added to this website as they are completed. As of October 2011, the newer maps are only available for the southern coast (Bandon to OR/CA border) and Cannon Beach. Sections of the coast marked by diagonal lines are currently unmapped and will have evacuation maps by 2013. Maps developed for the Oregon coast will eventually include the TWO evacuation zones.
The Washington Department of Natural Resources, in partnership with NOAA, completed 1st generation evacuation maps of selected portions of the Washington coast between 1998 and 2010 based on the maximum inundation expected for a LOCAL Cascadia tsunami. Modeling and mapping in Washington used the same earthquake source scenarios developed for the Oregon coast in developing their 1st generation tsunami evacuation maps. Maps developed for the Washington coast include only ONE evacuation zone.
Tsunami Warning Siren
Tsunami Bulletins are issued when events might affect the west coast.
Current Tsunami Bulletins For The West Coast
Know The Natural Warning Signs Of Tsunami
Strong local earthquakes may cause tsunamis. If the shaking causes you to fall or to have difficulty standing, this is your first natural tsunami warning sign. First, protect yourself from the earthquake effects. When the shaking stops, immediately leave the evacuation zone.
Receding water. As a tsunami approaches the shoreline, it could possibly expose the ocean floor, reef, and fish.
Seeing or hearing the water. You might see an approaching wall of water and/or hear a load roaring sound similar to that of a train or jet aircraft.
Tsunami Message Definitions
Tsunami Warning: A potentially destructive tsunami is imminent or expected. Warnings alert the public that widespread, dangerous coastal flooding is possible and may continue for several hours after the initial wave arrives. Appropriate response to the tsunami threat may include evacuating beaches and low-lying coastal areas and repositioning ships to deep water when there is time to safely do so.
Tsunami Watch: Alerts emergency officials and the public that a potentially destructive tsunami may later impact the Watch area. Therefore, appropriate actions should be taken to monitor the event and prepare to evacuate if the Watch is upgraded to a Tsunami Warning.
Tsunami Advisory: Advises public of potential threat of tsunami that may produce strong currents or waves dangerous to those in or near the water. Significant widespread inundation is not expected.
Information Statement: Informs emergency officials and public that an earthquake has occurred. There is little or no threat of a destructive tsunami.
To learn more about the tsunami warning system visit the NOAA Tsunami Website
The Oregon State Emergency Alert System (EAS) is used to notify the public of a possible approaching tsunami. A steady three minute siren tone is the attention alert signal. Turn on the nearest radio or television and listen for emergency information and instructions.
In some cases not all radio or television stations may be able to transmit. As part of the EAS, particular radio stations have been designated as primary sources for information. Click the link below to find out more about these stations.
The State and County Civil Defense Agencies test the EAS at 11:15 a.m. on the first workday of the month. When you hear the test sirens or your radio or television program is interrupted this is your opportunity to think about what you will do when it is not a test.
You cannot prevent a tsunami but you can be prepared for one. Actions you take now could save your life and the lives of your friends and family in an emergency.
Develop An Emergency Plan
Developing a family emergency plan will provide your family with information that could save lives and protect property.
Assemble An Emergency Preparedness Kit
Emergency preparedness kits should contain the essentials your family needs to survive during a disaster. It may take 72 hours or more for emergency personnel to reach you. Don't wait: hundreds of other families in your area share the same concerns, and it will be difficult to get access to the necessities you need due to shortages and competition.
Plan For Evacuation
If you live or work in a tsunami evacuation zone, identify an evacuation route from your home or workplace. Identify a safe area outside the evacuation zone where you and others can safely congregate.
After an earthquake, roads may become impassable or blocked so be prepared to evacuate by foot if necessary. Once you know your route develop the plan to evacuate. Consider securing your property, collecting pets, turning off the electricity and water, and bringing essential documents and emergency supplies.
Practice this evacuation plan with others so when there is a tsunami all are prepared to act.
If you are in a tsunami evacuation zone or a low-lying coastal area during a strong earthquake, move immediately to high ground outside of the tsunami evacuation zone - a tsunami could reach the shore within minutes.
The coasts of Oregon, Washington, and Northern California are exposed to two types of tsunami sources:
Of these, local Cascadia tsunamis pose the greatest hazard to people living along the PNW coast.
A Locally Generated Earthquake and Tsunami
Local subduction zone earthquakes and tsunamis occur without warning at any time of the day. The odds of you and your loved ones all being home when the earthquake strikes is slim. It is important that you and your loved ones know what to do, and what not to do. It is important to plan in advance. Make a family emergency plan.
What to do: The proper instruction is for everyone to individually survive the earthquake by ducking under something sturdy, covering your head from debris, and holding on until the shaking stops. When the shaking stops, immediately leave the building (if in one) and move quickly to high ground. High ground is 50 feet minimum to as much as a 100 feet for a locally generated tsunami. If you are already above 100 feet, stay there.
In most situations the fastest and safest way to move out of the tsunami evacuation zone may be on foot rather than by car. After an earthquake, many roads may be impassable by car, and traffic congestion and gridlock may block evacuation routes and lead to unnecessary accidents and ultimately death.
Remain outside the tsunami evacuation zone for at least 12-24 hours, as the tsunami surges will continue to flood and retreat for many hours. Do not survive the earthquake and initial tsunami surges only to die rushing back into the inundation zone. Stay at high ground overnight if necessary and then seek out loved ones.
Concrete and/or steel reinforced buildings of 6 or more stories that are not damaged by earthquakes should also provide safe shelter above the fourth floor.
Remain outside the evacuation zone until the "All Clear" signal has been issued by local emergency officials.
What not to do: Many people predetermine a location for everyone to meet following a disaster (school, home, hospital, etc.). This is potentially a bad idea. Why? Because it will encourage people to rush back into inundation zones too soon. In addition, some of these sites may be in the evacuation zone. This increases the likelihood of death. If you want to reconnect with your loved ones, teach them to have the discipline to STAY on high ground overnight before trying to reconnect.
A Distant Earthquake and Tsunami
In the event of a distant tsunami, such as the recent March 11, 2011 Japan earthquake, local emergency officials may order an evacuation in response to a National Weather Service tsunami warning. During such events, you have considerably more time to respond. If an evacuation is ordered, follow the directions of local emergency officials or move immediately to higher ground outside of the tsunami evacuation zone immediately. In some locations (e.g. the southern Oregon coast [Bandon to the Oregon/California border] and Cannon Beach), tsunami evacuations zones for a distant event have been developed. Use these additional maps to guide you outside the evacuation zone.
The first tsunami wave associated with a distant event may not be the biggest. Remain away from ports, harbors, and beaches and away from low lying areas for several hours, as the strong to-and-fro surges associated with the tsunami will continue for as many as 12-24 hours. These surges could potentially reach higher elevations if they occur around high tide.
If you have access to a concrete and/or steel reinforced building of 6 or more stories, move above the third floor.
Before returning to the evacuation zone, wait for the All Clear signal from emergency officials.
Bridges Can Be Weakened Or Damaged By Earthquakes
Earthquakes can damage or destroy bridges. When planning your evacuation route, avoid bridges if possible.
See Your Local Emergency Preparedness Agency For Specific Information On Tsunami Shelters And Other Specific Evacuation Instructions For Your Community
To reduce your risk you must first understand the tsunami threat.
A tsunami (Japanese for harbor waves) is a series of ocean waves produced by a sudden rise or fall in the earths crust, most commonly caused by an earthquake or underwater landslide. In the open ocean tsunami waves cannot be seen or felt by ships or airplanes because the unbreaking waves are actually hundreds of miles wide with a height of only a few feet. As the waves approach the coast their height increases dramatically and can be very destructive when they reach the shore.
Understand The Threat
All low-lying coastal areas, harbors, streams, and rivers in Oregon are vulnerable to tsunami impacts.
Tsunamis can occur at any time. Earthquakes and/or landslides that may trigger tsunamis cannot be forecast.
Locally generated tsunamis resulting from earthquakes or landslides can arrive at the Oregon coast within minutes, even before a warning can be issued. If you are near the shore and feel the ground shake, move inland to higher ground immediately. Oregon is also vulnerable to Pacific-wide tsunamis. These tsunamis result from distant earthquakes and/or landslides in places like Chile, Alaska, and Japan and can arrive on the Oregon coast within hours.
To understand your individual risk, find out if the places you and your family live and work are in or near tsunami evacuation zones. To learn about historical tsunamis that have impacted coastlines around the Pacific Ocean, visit the following websites:
The time it takes a tsunami to arrive depends on how far the earthquake is from our coastline.
Locally Generated Tsunamis
Locally generated tsunamis can arrive along our coastline within minutes of a significant earthquake. Earthquakes and landslides off the Washington, Oregon, or California coasts pose a serious local tsunami hazard for Oregon.
The figure below shows the time of wave arrivals for three Cascadia tsunami simulations using source inputs for three Cascadia subduction zone earthquake scenarios. The observations point is at the mouth of the Siuslaw River at Florence, Oregon. This figure should be used to understand approximate timing and relative wave height, not absolute wave height at the shoreline. Actual tsunami wave heights at the shoreline may be higher. Flooding caused by regional subsidence of the land surface during the earthquake may precede the first wave arrivals by 10 to 15 minutes.
Distant Source Tsunamis
Distant source tsunamis may take several hours to arrive on distant shores. The Alaskan Good Friday, March 28, 1964, earthquake had a moment magnitude of 9.2. The death toll in Alaska from this event was 115 people, with 106 of the deaths due to tsunamis. This tsunami also struck the Oregon coastline, killing four people and causing nearly $1 million damage (in 1964 dollars). The highest officially measured tsunami wave was 14.2 feet at the mouth of the Umpqua River. When the same tsunami struck Crescent City, California, the maximum wave height was 14 feet, 11 people were killed, and approximately $8 million of damage was done. Heights of tsunami waves generated by nearby earthquakes could be much higher.
Tsunami Travel Time Map for the March 28, 1964, Prince William Sound, Alaska Earthquake
This magnitude 9.2 Mw earthquake and ensuing tsunami caused 125 deaths and $311 million in property loss ($84 million and 106 deaths in Alaska). It was felt over a large area of Alaska and in parts of western Yukon Territory and British Columbia, its effects were heaviest in south central Alaska. The duration of the shock was estimated at 3 minutes. Vertical displacement occurred over 525,000 sq km. About 20 landslide tsunamis were generated; the tectonic tsunami devastated many towns along the Gulf of Alaska, left serious damage in British Columbia, Hawaii, and along the west coast of the U.S. (15 killed), and was recorded on tide gauges in Cuba and Puerto Rico.
Regional Tsunami Travel Time Map
This map shows the estimated regional tsunami travel time, in hours, to the Oregon Coast.