Avista Crews Remain Focused on Restoring Power Following Windstorm

Approximately 75% of customers have been restored.

Spokane, Wash. Dec. 18, 2025, 10:00 a.m.: Since yesterday, Avista crews have been working non-stop to restore power to approximately 80,000 customers originally impacted by Wednesday's windstorm. With the majority of assessments complete, estimated restoration times are now available for most customers. Crews continue to work around the clock to restore power as quickly and safely as possible. Avista remains well-staffed and additional contract crews arrived this morning and are assisting in the restoration efforts.

As of 10:00 a.m. Thursday, approximately 17,550 customers are without power, with more than 559 unique outage incidents. Approximately 75% of customers have been restored. Thursday, all available resources continue working to restore customer outages, including over 45 Avista line crews, 36 contract crews, 30 vegetation management crews. Dozens more Avista employees across the Company are also supporting the restoration effort.

Wednesday's windstorm caused widespread damage to Avista's infrastructure. The moisture on the ground caused by the recent rain combined with strong winds caused trees and vegetation to come into contact with power lines and poles, pulling them to the ground. Once the wind stopped blowing, Avista crews patrolled hundreds of miles of line navigating treacherous terrain and fallen trees and debris. They patrolled by foot, vehicle and helicopter to assess the damage in hopes of quickly restoring power to customers.

The remaining repairs will be time-consuming with hundreds of poles and miles of wire impacted across the system. One power pole can take up to 8 hours to replace. As power is restored throughout Avista's service territory crews will be reassigned to support the remaining restoration efforts until every customer has their power restored. Given the magnitude of devastation in certain areas, we now know some customers in the Silver Valley may not have power until Sunday.

Avista crews will press forward, continuing to work through the weekend. In some of the hardest hit areas customers may see outages from this event extended into Monday. With strong winds continuing in the coming days, Avista will be prepared to respond to new outages on its system.

Estimated restoration times are subject to change and available on our outage map located at myavista.com/outage.

Avista's Outage Support Hub will be stationed in a mobile van at the IGA in Saint Maries. Avista will provide charging stations, snacks, water, coffee, and access to our outage map for viewing. Employees of Avista will be on-site to answer questions and share the latest updates. Employees will be there from 10:30 a.m. to 3:00 p.m.

Ongoing restoration process

Once critical customers and transmission lines are restored, crews work to repairs distribution feeder lines that serve larger groups of customers. This will leave some customers may remain without power while their neighbors have been restored. Crews will return to address individual outages in neighborhoods, so customers may see service people multiple times. While restoration work may not always be visible, crews are working around the clock as quickly and as safely as possible.

What customers can do

Customers could see their neighbors power restored while they are still without power. This is common and we encourage those with power to turn their porch light on. Turning a light on serves as a signal to our crews that your power has been restored, which allows them to move through the area faster.

Customers can aid in the restoration process by checking their service equipment for needed repairs. All of these repairs need to be made by a licensed electrician before we can safely restore power to the home. If a customer's home sustained damage during this storm, the overhead mast may need attention and repair. The mast is usually located on the roof, where electric service connects from the power pole to the home. Customers should look for an overhead mast that is bent and pulled away from the house, causing a wire to hang, or to see if the bent mast broke the fitting where the wire connects to the electric meter. Customers should also look to see if they have a broken meter fitting that caused an arc or burned meter socket.

Safety during an outage

We want our customers to stay safe. Trees have brought down a significant number of power lines. Customers should treat all power lines as energized. Customers should stay away from downed power lines, not attempt to remove limbs from downed or sagging power lines, and should not drive over power lines. If customers see a downed power line, call 911 immediately and then Avista at (800) 227-9187.

Avista suggests customers take the following steps during an outage:

• Turn off all the appliances that were on before the power went out.
• Unplug electronic equipment, including computers.
• Leave a light or radio on as an alert when power has been restored.
• Help Avista crews working in a neighborhood know which homes have power by turning on the front porch light.
• Do not wire an emergency generator into a home's electrical system, unless there is a disconnect switch to separate generated power from Avista's distribution system. Back feed into power lines could injure or kill a lineman working to get electricity restored.
• Use a generator only to run specific appliances and locate it outside so poisonous carbon monoxide fumes do not enter the home. Please point exhaust away from home.

To find a licensed, bonded and insured electrician, customers can visit myavista.com/dealer-search.

About Avista Utilities

Avista Utilities is involved in the production, transmission and distribution of energy. We provide energy services and electricity to 422,000 customers and natural gas to 383,000 customers in a service territory that covers 30,000 square miles in eastern Washington, northern Idaho and parts of southern and eastern Oregon, with a population of 1.7 million. Avista Utilities is an operating division of Avista Corp. (NYSE: AVA). For more information, please visit myavista.com.

The Avista logo is a trademark of Avista Corporation.

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