Fireline last defense from Oregon wildfire

Firefighter Jesus Duran watches for stray fires as the backfire behind him climbs the hill.

CAVE JUNCTION, Oregon (CNN) -- A bulldozed firebreak was the last line of defense for about 17,000 southwestern Oregon residents Wednesday as a pair of wildfires raged out of control in the Illinois Valley, fire officials said.

The fire has been designated the top firefighting priority in the United States, officials said Wednesday.

A 24-hour evacuation order has been issued for the communities of Selma and Cave Junction and the surrounding areas, as the 145,000-acre Florence Fire and the 35,000-acre Sour Biscuit Fire threatened to merge.

The two fires had moved to within about two miles of each other Tuesday, and were only about 5 percent contained, said Tom Valluzzi, a fire information officer with the U.S. Forest Service in Cave Junction.

"If the winds come from the west, there's a good chance it could jump the lines, and that will mean evacuations for sure," Valluzzi said.

Firefighters worked with bulldozers through the night putting in the fire break, but high winds prevented them from setting planned backfires that would have secured the line. A "red flag" wind warning for Wednesday forced a further delay in completing the burnout.

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Heavy smoke and dangerous wind conditions have kept aerial tankers grounded for the past two days, Valluzzi said. But with the fire now a top priority, he expects the air attack to resume.

If the fire crosses the fireline along U.S. Route 199, the Fire Incident Command would notify the sheriff's department and the evacuations would be ordered, Valluzzi said.

Residents have already been notified to be ready to leave within 30 minutes after the evacuation notice is given. But Valluzzi pointed out that the evacuations would be voluntary.

"No one will be arrested if they refused to leave," he said, "but they'd better give the sheriff their next of kin."

Wednesday morning, a battalion of 500 regular Army troops, with support from the Oregon National Guard, was assigned to augment the 1,700 firefighters already on the fire lines in front of the Florence and Sour Biscuit fires. The soldiers from Fort Riley, Kansas, already were on fire duty in Oregon.

The two fires have grown exponentially since being sparked by lightning July 13 during a thunderstorm.

"This fire is uncontrollable," Jeff Gildehaus, fire information officer for the Forest Service said Tuesday. "There's a lot of concern."

Gildehaus said the extended drought in the Pacific Northwest has left "everything ... tinder dry. It's really hard to stop once a fire gets started."