Tsunami warning no cause for alarm on central or eastern peninsula

Oct 19, 2020

A 7.5 earthquake near Sand Point this afternoon triggered a tsunami warning in Kachemak Bay communities, as well as across the Aleutians and Alaska Peninsula. The warning has since been cleared.

Following the earthquake, which hit Sand Point around 12:54 p.m., residents of Homer and the greater Kachemak Bay area were told to get to higher ground and were beginning to evacuate. But residents across the peninsula were also warned, which was an error.

In Seward, the siren system alerted people of an impending threat. A message on the Kenai Peninsula Borough Facebook page explained that the mistaken sirens were due to an automated sequence of warnings for the peninsula’s coastal communities. 

The Facebook message said the National Weather Service is working with the borough’s Office of Emergency Management to fix that error. According to comments on that post and others, Seward residents had already started evacuating at that time.

Many central peninsula residents received tsunami warning messages to their phones shortly after 1 p.m. This summer, a 7.8 earthquake in nearly the same spot triggered a similar sequence of events.

“The tsunami warning system is highly automated when warnings first go out and that system causes multiple warnings to occur, both with our siren systems and also with cell phones, using a system called Wireless Emergency Alerts,” said Dan Nelson, of the borough’s Office of Emergency Management. “Based on how that system is built, which is a federal system, really each county has its own area. And so that works well in the Lower 48 where counties are small, but here on the Kenai Peninsula, we really only have one option, which is to send a warning message to everyone.”

“So that’s why here in the central peninsula and many other areas we’re not under any tsunami danger, but we still get those messages on our cell phones telling us to go to high ground,” Nelson added. “And it is because we aren’t able yet to really geographically target those messages with the technology that’s in place. So because we want to get that message out, it’s automated, we can’t stop it, it does end up going to everybody.”

A small tsunami of two feet was reported in Sand Point at 2:25 p.m.