Is a Tsunami possible in Santa Cruz County?

Ever since the earthquake last week, I have been overhearing my share of conversations, rumors, scare stories and general hub-bub about the possibility of a Tsunami in Santa Cruz County. Is a Tsunami possible in Santa Cruz County? The short answer is “yes”.

Here’s the long answer:

A fault located just offshore in the Monterey Bay, the San Gregorio fault, would be the most likely cause of a Tsunami in the coastal regions of the Monterey Bay. This fault follows the coastline for approximately 100 miles. This fault has had little recent activity, but an earthquake on this fault could create (and historically has created) a tsunami that would have a major effect on communities along the coastline.

According to the County of Santa Cruz’ Emergency Management Plan, “A tsunami generated by a Richter magnitude 6.8+ earthquake on the San Gregorio fault could arrive just minutes after the initial shock. The lack of warning time from such a nearby event will result in higher casualties than if it were a distant tsunami where the Tsunami Warning System for the Pacific Ocean could warn threatened coastal areas in time for evacuation.”

Don’t be scared… Be Prepared!

All tsunamis are potentially dangerous, even though they may not damage every coastline they strike. Damaging tsunamis are very rare. Our coastlines are vulnerable, but tsunamis are infrequent. Understand the hazard and learn how to protect yourself, but don’t let the threat of tsunamis ruin your enjoyment of the beach. Here are some Tsunami-specific preparedness steps. Remember, you can make sure your family is prepared for every disaster by visiting our FREE online resource Be Red Cross Ready!

In the aftermath of an earthquake, the WC/ATWC and PTWC may issue the following bulletins:

• WARNING: A tsunami was or may have been generated, which could cause damage; therefore, people in the warned area are strongly advised to evacuate.
  
• WATCH: A tsunami was or may have been generated, but is at least two hours travel time to the area in watch status. Local officials should prepare for possible evacuation if their area is upgraded to a warning.
  
• ADVISORY: An earthquake has occurred in the Pacific basin, which might generate a tsunami. WC/ATWC and PTWC will issue hourly bulletins advising of the situation.
  
• INFORMATION: A message with information about an earthquake that is not expected to generate a tsunami. Usually only one bulletin is issued

Be familiar with the tsunami warning signs.

• A strong earthquake lasting 20 seconds or more near the coast may generate a tsunami. A noticeable rapid rise or fall in coastal waters is also a sign that a tsunami is approaching.

• Tsunamis most frequently come onshore as a rapidly rising turbulent surge of water choked with debris. They are not V-shaped or rolling waves, and are not “surfable.”

If you are at risk from tsunamis, do the following:

• Plan an evacuation route from your home, school, workplace, or any other place you’ll be where tsunamis present a risk. If possible, pick an area 100 feet above sea level or go up to two miles inland, away from the coastline. If you can’t get this high or far, go as high as you can. Every foot inland or upwards may make a difference. You should be able to reach your safe location on foot within 15 minutes. After a disaster, roads may become impassable or blocked. Be prepared to evacuate by foot if necessary. Footpaths normally lead uphill and inland, while many roads parallel coastlines. Follow posted tsunami evacuation routes; these will lead to safety. Local emergency management officials can help advise you as to the best route to safety and likely shelter locations.

• ·Practice your evacuation route. Familiarity may save your life. Be able to follow your escape route at night and during inclement weather. Practicing your plan makes the appropriate response more of a reaction, requiring less thinking during an actual emergency situation.

• Use a NOAA Weather Radio with a tone-alert feature to keep you informed of local watches and warnings. The tone alert feature will warn you of potential danger even if you are not currently listening to local radio or television stations.

• Talk to your insurance agent. Homeowners’ policies do not cover flooding from a tsunami. Ask about the National Flood Insurance Program.

• Discuss tsunami with your family. Everyone should know what to do in case all family members are not together. Discussing tsunamis ahead of time will help reduce fear and anxiety, and let everyone know how to respond. Review flood safety and preparedness measures with your family.

Tsunami-specific supplies should include the following:

• Evacuation Supplies Kit in an easy-to-carry contanier (backpack) near your door

• Disaster Suplies Kit basics

• See: Be Red Cross Ready! for more information about disaster supply kits!!

If you have further questions about Tsunamis and Tsunami preparedness, please click here. or call us at 831-462-2881.