"The Border fire’s rapid growth from 35 to 46 acres in just a few days, combined with the deployment of significant resources and a total estimated cost exceeding $1.5 million, highlights the challenges of managing natural wildfires in remote Idaho terrain."
The Border wildfire, located in Boundary County, Idaho, was first discovered on August 25, 2026, and is caused by natural factors under the jurisdiction of the U.S. Forest Service. The fire initially burned 35 acres and grew to 43 acres by August 30, when it was reported as active, flanking, and backing. By September 1, the blaze had expanded to 46 acres and was 20% contained, with moderate, smoldering behavior. The fire later contracted to 37 acres and reached 83% containment by September 2, and was fully contained at 100% by September 7, with a final size of 35 acres. Throughout the timeline, containment progressed steadily while the fire’s behavior shifted from active to minimal, creeping, and smoldering.
Official source description: 3 Miles W from Porthill, ID
Minimal; Creeping; Smoldering
Moderate air quality. Unusually sensitive individuals should consider reducing prolonged outdoor exertion.
Nearest reporting station: Porthill (seasonal). Source: AirNow.gov (EPA).
The fire is now fully contained and exhibits minimal, creeping behavior. General wildfire safety guidance still applies, but no immediate evacuation or fire danger warnings are necessary at this time.
IRWIN ID: {BE3316BA-5063-458B-8D92-B8796F53D139}
Discovered: Aug 25, 2026
Cause: Natural
Managing Agency: USFS
Est. Cost to Date: $1,527,140
Coordinates: 48.9982, -116.7224
Other wildfires that have recently been contained or dropped from official tracking in ID.
The Border Fire has burned 35 acres as of September 7, 2026.
Yes, the Border Fire is fully contained (100%).
The official cause has been listed as: Natural.
The Border Fire is burning in Boundary, ID.
No, the Border Fire is no longer listed as active by NIFC.
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