The Big Grass Fire along the Oregon-Idaho border has grown to approximately 303,285 acres and remains 21% contained as of July 31, 2026, making it the largest single active wildfire in the United States. The blaze has prompted a state of emergency declaration, National Guard deployments, and mass evacuations across Owyhee County, Idaho, and Malheur County, Oregon.

Fire Status

The fire ignited during the mid-July lightning siege and quickly exploded through dry grass and sagebrush terrain in one of the West's most remote but ecologically sensitive regions. The Oregon-Idaho border area around Jordan Valley, Owyhee County, and Pleasant Valley has been the epicenter of firefighting operations, with crews working to protect ranches, livestock infrastructure, and rural communities.

As of the latest report, containment stands at 21% — a meaningful improvement from earlier in the week when the fire was only 5% contained — but crews warn that Saturday's forecast major wind event could rapidly undo progress and drive new runs through unburned fuel.

Evacuations and Emergency Declarations

Idaho Governor Brad Little declared a fire disaster emergency on July 29, authorizing deployment of the Idaho National Guard to support firefighting operations. The declaration covers Owyhee County and also encompasses recovery efforts for the separately contained Turner Fire in Boundary County.

The Owyhee County Sheriff's Office has issued Level 3 GO evacuation orders for multiple communities and areas, including:

  • Pleasant Valley
  • South Mountain
  • Jordan Valley area
  • Flint Creek Road corridor
  • Triangle Area and Triangle Reservoir
  • West portion of Mud Flat
  • Juniper Mountain

Residents under Level 3 orders must leave immediately. Officials have directed evacuees from Pleasant Valley to use Pleasant Valley Road toward Jordan Valley, then travel north on US Highway 95.

Scope of the Threat

The fire threatens more than 350 homes as well as significant ranching and agricultural infrastructure across a wide swath of high desert terrain. The Bureau of Land Management Owyhee Field Office has issued temporary closures for the entire area south of Trout Creek Road and Silver City Road to protect public safety and allow firefighting operations to proceed without interference.

What's Ahead

A major wind event forecast for Saturday, August 1 — with gusts potentially reaching 50+ mph through portions of the Northern Great Basin — poses the greatest immediate threat to containment progress. Fire weather forecasters have described the weekend conditions as "critical to locally extreme." Crews are pre-positioning resources and working to strengthen containment lines before winds arrive.