New eruption planning for Mt. Adams, Mt. St. Helens

SEATTLE - Mount Adams experienced increased seismic activity around the end of 2024. Now, leaders across the state are coming together to update their eruption coordination plans.

The precautionary measure includes updating a 2014 plan detailing the communication and information sharing plans between agencies during the event of an eruption at either Mount Adams or Mount St. Helens.

"We don’t really know when it’s going to erupt, what direction, how much ash is going to be, whether it will be days, weeks, months of unrest. So, the best thing we can do on a coordination plan is who has what responsibilities, who shares information, when and at what level, who reports to who," said Volcano Program Manager Brian Terbush at the Cascades Volcano Observatory in Vancouver.

The backstory:

Mount Adams usually gets one small earthquake every couple years. However, between September 2024 and January 2025, there were 12 recorded earthquakes--the largest was a 2.0 magnitude.

The increased shakes pulled scientists from the "high threat" volcano back in December while they were investigating increased activity. They had previously moved to install three earthquake stations two months prior.

"This is the volcano we expect activity to happen next and this is the one we want to be ready for," Wes Thelen, a geologist for USGS, told the coordination plan workgroup.

What's next:

The group of leaders will reassess their current plan, which helps describe roles and responsibilities between agencies.

The Washington Military Department shares the new plan will outline actions for preparedness, response, and recovery.

"Coordination is more of a list of roles and responsibilities, while your standard operating procedures are what you do in different situations," Terbush said. "So, having all of these people in the room, all of these people online, this is a good start."

The Source: Information for this article comes from the Washington Military Department.